Pe. 40 Ae) P Mrs. Walter E. Garrey 39 Orchard Avenue Waban, Massachusetts POPP Pee Pee eee eee eee USEFUL INFORMATION FOR THE CONCHOLOGIST inch (English) pouce (French) pollex (Latin) Zoll (German) Ligne (French) = 2.25 mm. line (English) = 2.11 mm. linie (German) = 2.18 mm. Lipa dd = 12 lines Ln ce oe oe oe ee oe | 3’ 4” 6” means 3 ft., 4 inches, 6 lines 1 inch = 25.37 mm. J = ale ee TTL a i, = female g = hermaphrodite 0 0301 0051854 O eal | ] 116 INCHES 1 ‘ 2 MM 4 7 | 3 4 ) LENGTH OF SHELL, ———> | | | | | y) = | | fathom = 6 feet meter = 39.37 inches nautical mile = 6,080 feet statute mile = 5,280 feet degree latitude = 60 nautical miles or about 69 statute miles | Temperature conversion (Fahrenheit-Centi- grade) pe C+ 32 5 Cer 4.) 9 3 3 4 3 6 ‘ F ~y ’ hum ‘ nog a ’ ‘ we 7 i nM Wis ; . . y 7 a wy Fs . ‘ we. EASY Mr anfees POUR RO TT 7 ii . as : f ’ se A ¥ ” 7 Se : hfe © ras? | whi sau. : Poy ed Mace 7 | ® AMERICAN SEASHELLS THE NEW ILLUSTRATED NATURALIST EDITORIAL ADVISORY BOARD WILLIAM BEEBE, Sc.D., LL.D. Director Emeritus, Department of Tropical Research New York Zoological Society AUSTIN H. CLARK Smithsonian Institution ROBERT CUSHMAN MURPHY, A.M., Sc.D. Chairman, Department of Birds, American Museum of Natural History FAIRFIELD OSBORN =- President, New York Zoological Society President, Conservation Foundation Pe Nps Ree NEV TELUS TRADED NATURALIST AMERICAN SHASHELLS BY Ry TUCKER ABBOTT. NS. Pilsbry Chair of Malacology Academy of Natural Sciences of Philadelphia WITH PHOTOGRAPHS «BY FREDERICK M. BAYER, B.S: United States National Museum Smithsonian Institution D. VAN NOSTRAND COMPANY, INC. TORONTO NEW YORK LONDON NEW YORK D. Van Nostrand Company, Inc., 250 Fourth Avenue, New York 3 TORONTO D. Van Nostrand Company (Canada), Ltd., 25 Hollinger Rd., Toronto LONDON Macmillan & Company, Ltd., St. Martin’s Street, London, W.C. 2 COPYRIGHT, 1954, BY D. VAN NOSTRAND COMPANY, INC. Published simultaneously in Canada by D. Van Nostranp Company (Canada), Lip. All rights in this book are reserved. Without written authorization from D. Van Nostrand Company, Inc., 250 Fourth Avenue, New York 3, New York, it may not be reproduced in any form in whole or in part (except for quota- tion in critical articles or reviews), nor may tt be used for dramatic, motion-talking-picture, radio, television, or any other similar purpose. Library of Congress Catalogue Card No. 54-5780 First Printing, March 1954 Second (Prepublication) Printing, March 1954 Third Printing, May 1955 PRINTED IN THE UNITED STATES OF AMERICA To my children Bossy, Carot, AND CINDY Preface This book wrote itself in response to the many hundreds of inquiries on seashells and other mollusks that have been sent to such museums as the Smithsonian Institution. Our natural heritage of seashore treasures has always been of keen interest to Americans, and in recent years there has been such an increase in shell collecting and biological investigations of mollusks that the need for a book like this has become apparent. American Seashells belongs to the amateurs, for it is their enthusiasm in searching beaches and bays and their limitless curiosity into the ways of mol- luscan life that have dictated the contents of this book. How do shells grow? How do they form their color patterns? How do they breed and what do they eat? are the kind of questions asked. But the greatest demand has been for a reliable and up-to-date identification work. This need has been felt not only by private collectors, but particularly by students of marine biology and those undertaking research in fisheries and ecology. In meeting these re- quirements, there has been an attempt to strike a balance between the palat- able, popular accounts and the more technical material. The illustrations, the standardization of popular names and the natural history accounts will be of particular interest to the beginner, and it is hoped that the monographic re- views, identification keys and the bibliographies will adequately serve the serious student. There are over 6000 species of mollusks living in North American marine waters, and a thorough treatment of them all would call for a book many times the size of this. The conchologist will find that the 1500 species discussed or illustrated within these pages include every kind of shell likely to be found in shallow waters, whether collecting is done in Labrador, Florida or along the western shores from Alaska to Lower California. While considerable original research went into many parts of this book, it should be kept in mind that a popular book covering such a vast fauna is merely an expression of the present state of knowledge of our science and that time and research by others will inevitably render sections of it obsolete. I would like to express my thanks to Dr. Leonard Carmichael, Secretary of the Smithsonian Institution, for granting permission to publish on and illus- trate specimens housed in the United States National Museum. Although the efforts involved in this project did not encroach upon official time, I would vu Vill Preface like to record my good fortune in being able to consult the National Museum collections on holidays and during after hours. Austin H. Clark stands fore- most as spiritual guide and counselor in the many intricacies of preparing a book for the public. Dr. Harald A. Rehder, curator of the Division of Mol- lusks, with whom I have been pleasantly associated for several years, has kept a weather eye on this project and in not a few instances has made valuable suggestions. I have gratefully and heavily leaned on the Minutes of the Conchological Club of Southern California which represents the work of John Q. Burch, A. Myra Keen, A. M. Strong, S. Stillman Berry and many others. Mr. Gilbert Voss kindly helped me with the section on squid and octopus. This is also true of Jobnsonia, a magnificent work produced by William J. Clench, Joseph Bequaert, Ruth D. Turner and others. I would also like to thank my friends in the National Museum for constant encourage- ment. The heaviest debt is to the countless amateur collectors of American mollusks. Were it not for their enthusiastic pursuit of shells and their un- selfish desire to share their treasures with our leading museums, our scientific collections undoubtedly would be half their present size. It 1s my sincere hope that this book, by its usefulness, will measure up to their kindnesses and friendships. Illustrations make the book, and American Seashells could not have been successfully completed without the aid of Frederick M. Bayer, Associate Curator in the National Museum, who is responsible for the colored plates, including the lovely paintings of western Atlantic nudibranchs. Most of the other photographs were also taken by him. Special thanks are due William J. Clench who made available all the photographs and drawings that have appeared in Johnsonia. The colored paintings of Pacific coast nudibranchs are taken from F. M. MacFarland’s “The Opisthobranchiate Mollusks from Monterey Bay, California, and Vicinity,” which appeared in 1906 in the U. S. Bureau of Fisheries Bulletin 25. All of the exquisite pen drawings of shells, unless otherwise noted, were executed by the U. S. Army Surgeon, John C. McConnell, in connection with researches done by William H. Dall of the U. S. Geological Survey. Our photographs of Florida Thorny Oysters are from specimens kindly sent on loan by Leo L. Burry of Pompano Beach, Florida. Notable credit is due Chanticleer Company of New York City which took such pains in the preparation of the colored plates, and to the printer who retained with such remarkable fidelity the beauty of the original photographs. Rea A: Washington, D.C. September 15, 1953. Contents CHAPTER Preface List of Plates . Ab Foreword by H. A. Pilsbry . Part I—Tue Naturat History or SEASHELLS Man and Mollusks Life of the Snails Life of the Clams : Lives of the Other Mollusks . Collecting American Seashells How to Know American Seashells . Part II—GuImpE To THE AMERICAN SEASHELLS Class Gastropoda (Periwinkles, Conchs and Other Snails) . Class Amphineura (Coat-of-mails and Other Chitons) . Class Scaphopoda (Dentaliums and Other Tusk-shells) . Class Pelecypoda (Scallops, Oysters and Other Clams) Class Cephalopoda (Squid, Octopus and Cuttlefish) . Guide to the Molluscan Literature . Index to Subject Matter and Common Names . Index to Scientific Names . List of Plates PLATE on AM Pw KN & BETWEEN PAGES 114 AND II5 (IN COLOR) The Five Classes of Mollusks Pacific Coast Abalones Turbans, Top-shells, Star-shells Nerites, Purple Sea-snails, Sun-dials Conchs, Tritons, and Moon-shells Cowries Sea-whip snails Living Flamingo Tongues on the Rough Sea-whip, Muricea muricata Pallas Bonnets, Tuns, and Frog-shells Murex Shells and Royal Tyrian Purple Spindles, Dwarf Olives and Marginellas Olive Shells Atlantic Tulips, Spindles and Volutes Atlantic Cones New England Nudibranchs Pacific Coast Nudibranchs BETWEEN PAGES 210 AND 211 (IN BLACK AND WHITE) Atlantic Coast Univalves—Limpets and Arenes Pacific Coast Univalves—Limpets and Tegulas Atlantic Coast Univalves—Periwinkles and Ceriths Pacific Coast Univalves—Periwinkles and Nassas Atlantic Coast Univalves—Worm-shells and Trivias Atlantic Coast Univalves—Wentletraps and Cones xi Xll List of Plates BETWEEN PAGES 210 AND 2II (IN BLACK AND WHITE) 23 Atlantic Coast Univalves—Conchs and Whelks 24 Pacific Coast Univalves—Purpuras and Neptunes 25 Atlantic Coast Univalves—Rock-shells and Doves 26 Atlantic Coast Univalves—Miters and Bubbles 27 Atlantic Coast Bivalves—Scallops and Arks 28 Atlantic Coast Bivalves—Oysters and Astartes 29 Pacific Coast Bivalves—Mussels and Semeles 30 ~=©6Atlantic Coast Bivalves—Lucines and Tellins 31 Pacific Coast Bivalves—Cockles and Venerids 32 Atlantic Coast Bivalves—Venus and Macomas BETWEEN PAGES 402 AND 403 (IN COLOR) 33. Large Scallops 34 Small Scallops 35 Pearl Oysters and Mussels 36 ‘Thorny Oysters 37 Jewel Boxes 38 Atlantic Oysters, Lucinas and Venus Clams 39 Venus Clams and Cockles 40 Semeles and Tellins Foreword Shell collecting is now taking its place as one of the major outdoor diversions. It has advantages over such pursuits as bird watching or fishing, for you may have even more pleasure in studying your catch at home than in the time spent afield. The thrill of finding a shell new to you, or of watch- ing some rare snail going about its watery affairs, is ample reward for the sunburn and stiff neck you may have from wading around too long with a water-glass. Hours sieving dredgings are counted well spent if a fine volute or turrid turns up in the seaweed and rubbish. American Seashells gives a comprehensive and well-rounded view of the Mollusca in nontechnical language. It is easy reading for the beginner, but it contains also material indispensable to the advanced malacologist. The chap- ters on nudibranchs and pteropods are especially welcome, for these beautiful animals have always been slighted in American books. In chepats on the life of the snail and the clam, with the author we “listen in” to the current of molluscan life. The shells become living things, moving and breathing, feeding and mating. One perplexity of the novice is that different books may give different names for the same shell. The causes of this diversity are explained on a later page. With the facilities of the largest museum in America, the author has been able to speak with authority in those matters of nomenclature. When the problem is zoological and still to be solved by further collections, or by the study of living mollusks, then the cooperation of the keen collector may give the answer sought. Professional malacologists are few. Their work is largely in museums with dead animals. The interesting but long task of collecting from a thousand miles of coast, and observing mollusks alive, has always been in large part a labor of love by private naturalists. Our science owes nearly as much to them as to the work of professional zoologists. The author belongs to the younger group of malacologists, but he has cultivated the society of mollusks in many lands, from East Africa, the X1i1 X1V Foreword Philippines and Guam to our Atlantic coasts. His original research covers a wide range, and is at its best in dealing with some neglected or little-known shellfish. This book will do much to increase the knowledge and enjoyment of all of us who hunt the elusive mollusk. Henry A. PILsBry Curator of Mollusks Academy of Natural Sciences of Philadelphia PART. | The Natural History of Seashells CALA Posh Reet Man and Mollusks SEASHELLS and man were closely associated even before the dawn of civiliza- tion when primitive man gathered snails, oysters, and other kinds of mollusks along the seashore for food, implements, ornaments, and money. The many kitchen-middens and burial sites in nearly every corner of the world reveal the great extent to which early peoples were dependent upon mollusks. On some coral islands, as, for instance, Barbados, where there was no available stone, nearly all domestic utensils, including knives and axes, were made from seashells. As civilization became more complex, specialization in the use of mollusks increased. From them were obtained dyes, inks, textiles and win- dowpanes. In the Mediterranean region there was a long period when an entire commercial empire owed its origin and continued success to the Tyrian purple obtained from a seashell. Later, in Roman times, the farming of oysters and edible snails became a major enterprise. Today the uses of molluscan shells are legion. Jewelers, artists and but- ton manufacturers; biologists, geologists and archaeologists; bird and aquarium dealers; all daily use mollusks or their products. In recent years there has flourished in Florida a five-million-dollar-a-year seashell industry. Through- out the country, the hobby of shell collecting is enjoyed by countless thou- sands, and it now rivals the popularity of coin collecting. Local and federal agencies are investing millions in research directed toward the more efficient cultivation and utilization of commercially important mollusks. From another standpoint of perhaps even greater importance mollusks have influenced the activities and welfare of man. Some are extremely de- structive to wooden structures in the sea, and others are a serious menace to health, mostly as intermediate hosts to dangerous parasites or as carriers of 3 4 American Seashells poisonous micro-organisms. Prior to the advent of ships with metal hulls no vessel on the seas was safe from the borings of molluscan “shipworms.” Many ships have disappeared at sea as a result of being weakened by the attacks of these creatures. Even today damage to the extent of millions of dollars is done every year to wharf pilings, small craft, and hemp lines by these bivalves. In many parts of the world the health of millions is seriously menaced by mollusks. It was not until the turn of the century when modern research was directed toward tropical diseases that the full importance of snails as carriers was appreciated. Six major parasitic diseases have been shown to be transmitted by fresh-water mollusks. Thousands of people die each year in China and Egypt from the blood-fluke disease alone. No fatal snail-borne disease is present in North America proper, but visitors to the West Indies and northern South America are warned to keep out of ponds and flooded ditches in these regions. In other respects, mollusks are of minor medical importance. A number of parasitic diseases of sea birds and fish are carried by marine shells, such as the periwinkles Littorina and Tectarius and other shore species. During cer- tain seasons of the year, usually in late summer, these snail hosts shed thou- sands of microscopic larval worms into the sea water. Although normally destined to penetrate the skin of birds, these tiny creatures sometimes attack man and cause an uncomfortable rash or “swimmer’s itch” which is often mistaken for jellyfish sting. Among the most dangerous inhabitants of the coral reefs in the tropical RADULAR TooTr FicureE 1. The large cone shells of the Indo-Pacific, and possibly those of the Atlantic, can inflict a serious, and at times fatal, sting. The venom leaves the poison sac and, together with the tiny, harpoon-like tooth, is eyected from the snail’s pro- boscis and stabbed into the skin of the victim. Man and Mollusks 5 Indo-Pacific are the cone shells (Conus), the sting of which is as powerful as the bite of a rattlesnake. Although the beautiful cone shells are among the commonest of Indo-Pacific mollusks, the total number of authentic cases of death from their sting is surprisingly small. No American species have been recorded as harmful to man but, because all cones possess the necessary apparatus, it would be wise to be careful in handling American specimens over two inches in size. The number of cone stings is few because of the shy nature of the ani- mal. Invariably a snail will withdraw into its shell when disturbed and, unless the cone is held quietly in the palm of the hand for some minutes, there 1s little likelihood of the collector being stung. The apparatus for the injection of the venom into the skin of the victim is contained in the head of the animal. Bite, rather than sting, is perhaps more descriptive of the operation. The long, fleshy proboscis or snout is extended from the head and jabbed against the skin. Within this tube are a number of hard, hollow stingers, as long and slender as needles. These are actually modified radular teeth, com- monly used in other snails to rasp their food. Under a high-powered lens the teeth of the cone shell resemble miniature harpoons. As the teeth are thrust into the skin, a highly toxic venom flows from a large poison gland located farther back in the head, out through the mouth, and into the wound through the hollow tube of the tooth. In some cases, death has taken place in four to five hours after the patient was stung. Not all cases are serious. Andrew Garrett, a famous shell collector of the latter half of the nineteenth century, reported that he was sine by a tulip cone that caused a “sharp pain not un- like the sting of a wasp.’ While in recent years the cone shells have received perhaps an cndce amount of notoriety as dangerous creatures, they are best known as an aris- tocratic family of beautiful shells which have been favorites for years among the most discriminating of collectors. For hundreds of years the sound of the auctioneer’s gavel has been heard at the sale of valuable collections of sea- shells, but no shell has created such fevered interest as the Glory-of-the-Seas cone. Its present-day value is in the neighborhood of $400 to $600. This species seems to possess the ideal combination of features which brings high prices—beauty, size, rarity and, above all, mystery or legend. Although the legends connected with the Glory-of-the-Seas are for the most part untrue, the mere mention of its name will invariably cause the blood pressure of shell collectors to rise. The first published reference to the Glory-of-the-Seas was in 1757. Today the whereabouts of each of the twenty-three specimens is known. The most famous finding was made by the renowned shell collector, Hugh Cuming, in 1838 when he found three specimens at low tide on the reefs at Jacna on Bohol Island in the Philippines. The myth has often been repeated 6 American Seashells that Cuming returned for more only to find that the reef had sunk during an earthquake, and that since then no other specimens have been found. How- ever, the species is apparently widespread throughout the East Indian region. Specimens have turned up since Cuming’s day at Cebu in the Philippines, Am- boina Island, and Piru Bay in the Dutch East Indies. A four-inch specimen was found on the shore at Wahaai, Ceram Island, after a storm in 1896. In addition to the existing twenty-three specimens, three were destroyed during World War II and eight, formerly known to exist, are missing. A search in grandmother’s attic or along some East Indian beach will doubtless bring others to light. Collectors of fancy seashells are constantly in search of specimens of outstanding qualities, and although a number of species are well-known for their high value or unusual beauty, the standards by which we judge their rarity and attractiveness are considerably varied. The differences in our appreciation of beauty are natural enough, for the colors, forms and textures of seashells are numerous enough to offer appeal to almost any type of aesthetic appreciation. The man who covets a brilliantly patterned Olive shell of rich golden-red colors may see little in a tiny white shell which another collector treasures for its intricate snow-flake sculpturings. For many conchologists rarity 1s gauged by the top price that a specimen may bring; for others the important judging point is the scarcity of the spe- cies in nature or perhaps the rarity of specimens in collections. Left-handed, double-mouthed or distorted specimens, like misprints in stamps, are highly valued by many veteran collectors. There are literally hundreds of truly rare species, but most of these are deep-sea shells, some of which are known only from a single specimen. Most of these are small and not particularly attrac- tive. The high-priced shells are found among the showy genera, like the cones, Pleurotomaria slit-shells, volutes, murex shells, scallops and cowries. The Golden Cowrie is the most popular among the so-called rarities, the present-day price ranging from $20 to $60. Some species may be considered rarities for years and command very high prices, until they are collected in large quantities. The Goliath Conch (Strombus goliath) is worth about $200 today, but collecting 1 in northern Brazil would undoubedly bring them to light in great quantities and hence would lower the price to a few dollars. The Precious Wentletrap Shell (Epitonium scalare or pretiosum) of the western Pacific was in such demand years ago that Chinese found it profit- able to make counterfeits out of rice paste. The species is now considered reasonably common and is low-priced, but genuine rice counterfeits are now rare and equal in value to the price of the first-known shell specimens. Some of the most interesting threads of man’s early history have been woven around the trade routes of primitive peoples and their dispersal of shells. The discovery by archaeologists in 1895 of the Red Helmet Shell Man and Mollusks i (Cy praecassis rufa) in a grave of the prehistoric Cro-Magnon man in the caves of France was of considerable importance in tracing former trade routes. This species is found only in the Indian and Pacific oceans. Its pres- ence substantiated other archaeological evidence that extensive trade routes for great distances existed among early European man. The Tiger Cowrie (Cypraea tigris), another Indo-Pacific species, has been found in a prehistoric pit-dwelling at St. Mary Bourne at Hants, England, and the Panther Cowrie (Cypraea pantherina), a Red Sea species, has been found in Saxon women’s graves, excavated in several localities in Kent, England. The seashell with perhaps the widest dispersal by the ancients and modern man is the small, yellow Money Cowrie (Cypraea moneta) which was for many centuries the accepted currency in many parts of the world. Although its natural biological distribution is limited to the vast areas of the Indian Ocean, the East Indies and the islands of the tropical Pacific, its use as currency or for ornamentation has been almost worldwide. The three most unusual records are those located in North America. When the aboriginal sites along the Tennessee River were being investi- gated at the beginning of this century, five Pacific Money Cowries were un- earthed from one of the graves of the Roden Mounds in Alabama. Evidence points to the fact that these burials had been made before the mound makers had any intercourse with white man. The shells were sent to the United States National Museum by their discoverer, and Dr. William H. Dall wrote the following interesting reply: — I should incline to the belief that the cowries were imported in or about the time of Columbus’ voyages. Bound, as they supposed, for the Indies, where the cowry was formerly (like our wampum) a staple article of barter, the exploring vessels would have undoubtedly carried cowries as well as other articles of trade we know they carried. It would not have taken them long to find out that cowries did not pass as currency with American natives, and reporting this on their return to Spain later traders would not have carried them for barter. The necklace or bracelet you obtained may have passed from hand to hand as a curiosity (as I have known such things to do) until it reached a people who knew nothing of whites ’till much later. In fact your cowries may have come off one of Columbus’ own vessels. If not from one of Columbus’ ships, these shells more than likely were brought over from Europe soon afterward by early Spanish explorers. It does not seem so plausible to assume, as some ethnologists do, that these shells were brought by migrating tribes from eastern Asia to America via the Bering Straits long before the time of Columbus. The Lewis and Clark Expedition brought back in 1805 a handsome dress. possibly of Cree origin, which was adorned with four dozen Money Cowries. 8 American Seashells Another Money Cowrie was unearthed near the so-called Onatonabee Ser- pent Mound of Peterboro County in Ontario, Canada. It is most likely that in both of these cases the shells were the remnants of the Hudson’s Bay Com- pany’s shell stock which was bartered with the Cree and other Indians well before the time of the Lewis and Clark Expedition. A lively trade in marine shells took place for centuries among the pre- Columbian peoples of southwestern United States. Archaeological studies in that area have been able to confirm the existence of trade routes which then existed from three principal geographical areas, one along the coast of south- ern California, a second from the Gulf of California, and the third on the Atlantic side from the coast of the Gulf of Mexico. Ficure 2. Major sources of trade shells used by the early American Indians. a, tusk-shells. Dentalium, used for money; b, abalone shells, Haliotis, and the neck- lace shells, Olivella; c, Glycymeris clams for bracelets; d, olive shells, helmet shells, Cassis, and many others; e, large whelks, Busycon, and Venus clams; f, wampum from the Venus clam, Mercenaria mercenaria. Marine shells were used primarily as ornaments. Beads of glossy Olivellas and Olive shells were by far the most popular throughout the esti- mated 1000-year span of trading. Pendants, bracelets, rattles, trumpets and carved shells were popular in that order. Pacific Coast shells were passed on from settlement to settlement to a limited extent by the early Basket Makers (?-500 A.D.) and, with the rise of the late Basket Makers (500-700 A.D.), trading increased from both the Pacific Coast and the Gulf of California. Man and Mollusks 9 It was not until Pueblo times that the Atlantic trade reached the southwest when the Pacific trade was also at its zenith. For years archaeologists were puzzled by the absence in New Mexico of residue shell material which ought to be present wherever bracelets of the Glycymeris clam appear. Not until 1930 were the hundreds of ancient manu- facturing centers discovered along the Sonora coast of the Gulf of California. There the early Indians sawed out patterns and ground down the clams to a smooth finish. The existence of this industry in the areas where the clams live illustrates one of the fundamental problems of prehistoric trade where beasts of burden were unknown and all goods were carried on men’s backs. The finished product was not only much lighter, but also brought a better price. The Mohaves used a trade route from the Pacific Coast in the vicinity of Los Angeles across the mountains into Nevada and Utah, and they perhaps have the rightful claim to the title of the “Phoenicians of the West.” Several routes extended from the Sonora coast of the Gulf of California up to the Gila basin to Pecos in northwestern New Mexico. Around this area there is evidence that the Pacific and Atlantic trade converged during Pueblo times. It is quite likely that Pecos was a trading pueblo between the southwestern peoples and the plains tribes. In the midwest of the United States an entirely separate trade route ex- isted from the Mound Builders of Illinois (Cahokia group) south to the Gulf of Mexico. Among the mounds of these prehistoric people the Cameo Hel- met Shell (Cassis), the Fighting Conch (Strombus) and the Apple Murex Shell have been discovered—all species from southern Florida or the warmer waters of the Gulf of Mexico. In recent times, the dispersal of mollusks has been little short of spec- tacular, particularly so if we may mention in this connection the many large collections that have been assembled in natural history museums. For the last 200 years there has been a steady flow of specimens to these study collections from all lands. Probably the largest mollusk collection in existence, that housed in the United States National Museum in Washington, contains over 9,000,000 specimens and represents about 45,000 kinds. This collection is the result of a century of labor on the part of thousands of ardent enthu- siasts who collectively have stooped to pick up mollusks in over 100,000 localities throughout the world. Added to the scientific traffic of material among dozens of natural his- tory institutions, is the constant and spirited exchange of specimens among thousands of private shell collectors. It is little short of miraculous that in a small Connecticut town one can find in an amateur collection a rare, ivory- like Thatcheria shell from 200 fathoms in Japanese waters or a 200-pound valve of the giant clam from the Great Barrier Reef of Australia. In a small cabinet of land mollusks in Boonton, New Jersey, you may find a giant Afri- 10 American Seashells can snail from the Belgian Congo or a tiny ground snail, no larger than a grain of rice, from the Himalaya Mountains of India. The locality labels attached to many of the shells in museums are milestones in recent history— Tobruk, Bizerte, Anzio—Port Moresby, Guadalcanal, Leyte Gulf—Pusan, the Han River, and Peking. Accidental dispersal of marine shells, even in large quantities, is not un- common, and many unusual cases have been recorded in newspapers and scientific journals. In the days when the beautiful ear shells or abalones of the Californian coast were used extensively for cabinet inlays, a sailing vessel bound for New York with a cargo of these shells went down in a storm just off Santiago on the south coast of Cuba. For several years, these magnificent shells were being cast ashore on the beaches, much to the delight of local collectors and small children. A similar case occurred in 1873 when the “Glendowra,” a four-masted vessel, homeward-bound from the Philippine Islands on a cowrie expedition, was wrecked off the coast of Cumberland, England. She had on board more than 600 bags of Money Cowries destined for use in the African trade and, during a heavy fog, ran ashore near Seascale. For years these shells were picked up in excellent condition on the nearby beaches. Many collectors, unaware of their history, regarded them as native to the British Isles. The necessity of taking on ballast to make up for light cargoes on return sailing voyages has been responsible for many introductions of exotic shells to United States ports. The Money Cowrie has been picked up on one of the beaches of Cape Cod and was presumably jettisoned there by a sailing ship returning from the Indian Ocean. Ballast Point in San Diego was years ago a fairly good place to collect Hawaiian shells and, during World War II, a dozen or more species of British marine shells brought in ballast could be found in the vicinity of Long Island, New York. Wholesale dispersal of marine shells has been carried out purposely by man on several occasions. With malice toward none, it may be said that con- siderable competition for the tourist trade exists between the Atlantic and Gulf coasts of Florida. Lacking the abundance of attractive seashells which are now considered prime tourist bait, the Atlantic coasters have made up for it by their aggressive ingenuity. It is reported that some Miami hotel owners have sent trucks to the rich beaches of the Gulf Coast, loaded them with molluscan spoils and brought them back to dump on their own relatively shell-less beaches. Mollusks have been used extensively in art and literature, and through- out history we find numerous uses of shells as symbols. In many parts of the world, and especially along our motor highways, the scallop shell is a familiar trademark to motorists. The “Shell” Transport and Trading Company had its origin in London, England, during the middle of the last century when Man and Mollusks 11 shell ornaments on boxes, screens and frames were popular in Early Vic- torian drawing rooms. The founding brothers, Marcus and Samuel Samuel, traded in shells from all parts of the globe, but as a side line they began to deal in the sale of kerosene. With the advent of the new “parafine oil” lamps and, later, the combustion engine, it was not long before they were market- ing oil exclusively. Soon afterward their company was merged with the Royal Dutch interests. Until 1904 they used a trademark emblem patterned after the Sun-rayed Tellin (Tellina radiata of the West Indies), but this was later replaced by the now world-famous emblem of the European Jacob’s Scallop (Pecten jacobaeus). The scallop on the letterhead of the company’s stationery is a fossil species from California. The 200-odd oil tankers of the Shell Oil Company are named after various genera of mollusks, the first ship launched being christened the S. S. Murex. Aboard each vessel, a specimen of her namesake mollusk is mounted in a glass exhibit case. Naming and securing shells for the first hundred ships was comparatively easy, but recently the choice of new names has resulted in the unfortunate selection of obscure genera based on rare and, in some Cases, microscopic species. Some ships bear names based on the same genus —nautical synonyms! The use of the scallop is a very ancient one. As a source of food and as an eating dish it was used in prehistoric times. It is pictured on the coins of the early Phoenician outpost of Saguntum (now Murviedro, Spain). All through the middle ages the scallop shell was used as a religious symbol, espe- cially in connection with pilgrimages to the shrine of Saint James at Com- postella and the crusades to the Holy Land. Three different popes granted a faculty to the Archbishops of Compostella to excommunicate all who sold scallop shells to pilgrims anywhere except in the city of Compostella. Today many of the family shields of England bear scallop shells, indicating that their ancestors made pilgrimages to the Holy Land. It is interesting to note that one of the earliest shell collections known to us contained a Jacob’s Scallop. This was unearthed from the ruins of Pompeii, together with Conus textile and the Pearl Oyster of the Indian Ocean, in what appears to have been a natural history collection. It is not beyond the realm of possibility that this was the remains of the Natural His- tory Society of Pompeii, of which the distinguished naturalist, Pliny, was probably a member. It was Pliny who first recorded the swimming activ- ities of the scallop, and he observed that it was able to dart above and skip along the surface of the water. In our modern age of synthetic dyes and highly mechanized textile industries, we little appreciate the part played by dye-producing mollusks in the history of the ancient civilizations of the Mediterranean. The power and fame of the Phoenicians, who were the great traders, navigators and 12 American Seashells colonizers of that region as early as 1500 B.C., were largely due to their monopoly of the Tyrian purple dye. The ancient cities of Tyre and Sidon (now Souro and Saidi in Lebanon) became great banking centers and the crossroads of commerce between Asia, Africa and western Europe. Although archaeological findings indicate that purple dye from species of Murex was in use in Crete as early as 1600 B.C. and in Egypt by 1400 B.C., these two Phoenician cities had managed to monopolize the industry and to expand their prosperous enterprises by 1000 B.C. The continual search for new beds of Murex is probably one of the reasons for their later colonization of Malta, Sicily, Utica, Carthage and Gades (now Cadiz). These ports served as trad- ing stations and, as evidenced by the great piles of unearthed Murex shells, as subsidiary purple dye factories. The imperial coins of grateful Tyre bore for many years the imprint of the Murex shell. It is interesting to note that the name Phoenicia comes from the Greek phoenix, “red,” which may well allude to the red or magenta color variations of the molluscan purple. It is now the general consensus that three species of marine snails were used in the Mediterranean. Although all three were present in many areas, the city of Tyre employed in the main Murex brandaris, while the great banks of shells discovered near Sidon in recent times were almost exclusively made up of Murex trunculus (see plate 10, figs. 1 and }). The “buccinum” of the Roman naturalists probably was Thais haemastoma. The high cost of the purple dye was largely due to the long and arduous process of manufacture. A recent experimenter used about 12,000 specimens of Murex brandaris before obtaining 1.5 grams of pure dye, and he estimated that one pound of dye in ancient times was worth from $10,000 to $12,000. The dye-producing fluid is exuded from an elongate gland which is situated on the inner wall of the mantle between the rectum and the gills. The fluid is colorless to milky-white when first produced, but when exposed to direct sunlight, it changes immediately to bright yellow, then passes through shades of pale-green to bluish and finally red-purple. During this photochemical process a strong odor is given off which resembles rotting garlic. The Tyrians collected vast quantities of living snails and ground up the smaller specimens in caldron-shaped holes in the rocky shore. Larger specimens were cracked open and the gland-supporting mantle ripped off and thrown into the holes. Salt was added to this juicy mass to prevent excess rotting, and then the sun was allowed to act on it for two or three days. This material was transferred to vessels of tin or lead and then diluted with five or six times its bulk in water. A ten-day period of moderate boiling fol- lowed, during which time the scum was constantly removed. Test pieces of wool were allowed to soak for five hours to ascertain if the desired strength of dye had been reached. Our modern concept of purple is quite different from that of the Man and Mollusks 13 ancients. They understood it as several colors ranging from dull crimson and magenta to violet-purple. The most expensively dyed cloth was made in Tyre and was more on the order of a dull red. In Sidon, where Murex trunculus was mainly used, the color was closer to our modern idea of purple. The wide range in hues of Tyrian purple was brought about by different strengths of, and varied techniques in making, the dye, including the double- dip system of dibapha in which the first bath consisted of extracts from Thais and the second dip taking place in Murex dye. The type of cloth and weave also produced wide variations. There is no question that cloth dyed with Tyrian purple was extremely valuable and at times vied in value even with gold. Hence it was reserved for the use of the wealthy and the hangings of temples. The Babylonians are said to have used it for the dress of their idols. A few of our museums pos- sess small pieces of Egyptian mummy wrappings which were dyed with Tyrian purple. However, it is necessary to make a chemical analysis to prove the presence of this dye, for the ancients were able to produce a similar color by double dyeing with indigo and madder. The Bible makes several references to this valuable purple. Moses used it for the works of the tabernacle, as well as for the clothing of. the high priest. Among the presents which the Israelites made to Gideon were purple rai- ments that belonged to the kings of Midian. Much later, according to Acts 16, verse 14, a seller of purple from Thyatira was converted by St. Paul at Philippi. Aristotle and Pliny both gave fairly detailed accounts of the industry widespread throughout Asia Minor. Plutarch records that when Alexander took possession of Susa he found among the treasures of Darius 5000 talents in weight (290,000 pounds) of purple cloth. Athenaeus states that the dye was extensively used as a cosmetic and was applied as a lipstick and rouge in Rome. At the fateful battle of Actium, the ship of Marcus Antonius and Cleopatra was distinguished from the rest of the fleet by having sails solidly dyed in Tyrian purple. It is difficult to believe, as many authorities claim, that the Tyrians kept the process a secret even for a short time, for we find that factories existed throughout most areas in the Mediterranean. In Rome only senators were allowed to wear a broad purple stripe (Jatus clavus) around the opening of the tunic. Laws were finally introduced by Nero and again by Theodosius (379-395 A.D.) prohibiting the wearing of Tyrian purple except by the Emperor himself. Except for its later use by the Christian church, especially in cardinal cloaks, the crimson color ceased to be worn or manufactured after the fall of the Roman Empire and the con- quest of Tyre by the Arabs in 638 A.D. It would scarcely pay to revive the industry except perhaps as a novelty item for tourists. The color is not par- ticularly exciting to the modern eye, and, in addition, it may be synthetically 14 American Seashells produced at low cost, so that one has no assurance that a souvenir textile is actually dyed with molluscan purple. The Mediterranean area and the west coast of Africa were not the only regions where mollusks were used for dyeing. In the British Isles the art seems to have been known from very early times. The Celts of England and the Lake Dwellers of Ireland (about 1000 B.C.) used the common Thais lapillus which 1s also abundant on New England shores. As late as the eight- eenth century this species was used for marking linen in England, Scotland, France and Norway. The French used molluscan purple to dye the parch- ment of rare books, some examples of which are still bright after 800 years. Had the Phoenicians possessed the compass and ventured to the West Indies, they would have marveled at the abundance of our Wide-mouthed Purpura, Purpura patula, and its large production of rich violet dye. Collec- tors who have put live specimens in a cloth bag will recall the bright, durable stains that have appeared soon afterward in the fabric. Many shell collections contain this species in which specimens still retain purple stains on the out- side of the shell. The subspecies, pansa, was used in prehistoric times for dyeing cotton on the northwest coast of South America and the west coast of Central America. Even today the Tehuantepec Indians of Mexico use the Pansa Purpura for dyeing cotton threads. The natives have put into effect a plan of conservation and, instead of crushing the shells, they carefully “milk” the living specimens by pressing in the animal to squeeze out the juice. “They then return the mollusks to the rocks and revisit them at a later date. The cotton threads are individually drawn through the liquid to obtain the fast dye. In 1711 Reaumur accidentally discovered that the egg capsules of Thais lapillus were a simpler and more abundant source for the purple dye. As Murex egg capsules mature, they take on a characteristic purplish hue. It is possible that this was the secret, if such existed, that the Tyrians guarded so jealously. Latest experiments indicate that the purple dye is a derivative of indigo containing bromide. Probably most, if not all, species of Murex, Thais, Purpura and other members of the Muricid family produce this bromide, dye-giving secretion. It has been suggested by some workers that this secretion serves as an anes- thetic on various oysters, clams and chitons upon which they prey. How- ever, the presence of purpurase in the egg capsules does not favor this view. In addition, the dye-producing gland is closely associated with the reproduc- tive system and not with the salivary glands or any other organs of the proboscis. Many other carnivorous families which attack other ‘living mol- lusks in a manner similar to that of the Muricids do not produce this dye. Inks and dyes are produced by many other mollusks, the Sepia cuttlefish being an outstanding example. Purple dye has been recorded in the Purple Man and Mollusks 15 Sea Snails, Janthina, in the Wentletraps, Epitonium, in some of the Mitras and Olive shells and in the sea hares, Aplysia. Vhese substances are known to be irritating to fish and other would-be predators, and its purpose as a defense mechanism seems most likely. Probably future experiments will show that the egg capsules of Murex, loaded as they are with purpurase, are dis- tasteful to fish and have an unusually high survival value. CHAP TE Rell Lite of the Snails TuE private lives of the snails, or gastropods as they are more correctly called, are almost as varied as the different kinds of seashells that are found along our beaches. More than half of the 80,000 species of existing snails live under marine conditions, the remainder being air-breathing land species or inhabitants of fresh water. In their evolutionary struggle for existence, they have shown an amazing diversity in adapting themselves to nearly every con- dition found in the sea. There are snails that creep, jump, swim, burrow, some that are permanently anchored to rocks and a few that live inside other marine creatures. In a few cases, as in some conchs and top shells (Trochus), the snail may play host to small fish and tiny crabs. Gastropods have experimented in all manner of forms, colors and sizes. In size they vary from the two-foot-long Horse Conch of Florida (Pleuro- ploca gigantea) to the microscopic Vitrinellas that scarcely exceed the size of a grain of sugar. Some species display unusual ornamentation and, as in the Murex shells, produce long, delicate spines. There are few objects in nature that can vie in beauty with the glistening sheen found in the shells of the olives and cowries. On the other hand, the beautiful sea slugs or nudi- branchs may entirely lack a shell. The Carrier Shell, Xenophora, has ac- quired the strange habit of collecting shells, bits of coral and other hard objects, and cementing them to its own shell. WHERE THEY LIVE From the high levels of the coastal cliffs to the canyons of the ocean’s bottom, a thousand kinds of habitats have been adopted by marine gastro- 16 Life of the Snails 17 pods. A few species of nerites and periwinkles are known to ascend trees near the seashore, although tree-dwelling is best known among certain tropi- cal land snails. In the tropics, the Tectarius prickly-winkles habitually live in or near splash pools along the rocky coast where spray from the waves and drenching rains are constantly changing the temperature and salinity. When the pools are dry the snails are often able to withstand weeks of hot sun and parched conditions. Three kinds of snails in American waters are forever destined to wander at large on the surface of the open ocean. The purple Janthina snails are born, live and, in most instances, die at sea. These pelagic snails live upside down and remain at the surface by means of a small raft of bubbles. Small bubbles of air are entrapped in a special mucus secreted by the animal. This clear fluid congeals upon contact with salt water and air, and it adheres to the foot. The entire float has much the appearance of crumpled cellophane. The female attaches her small eggs to the underside of the float where they are partially shaded from the sun’s rays. The Janthinas live off the coasts of our southern states, and during certain seasons they are commonly cast ashore in California, Florida and the Gulf States. Specimens have been blown off their Gulf Stream course and been washed ashore in New England and even the British Isles. As is the case with so many other pelagic creatures, the shell surface of Janthina which faces downward (the spire of this upside down shell) 1s colored a light, milky blue. This is probably a protective coloration which blends with that of the surface of the sea, which to an underwater observer is similarly colored. For some unknown reason Janthinas are completely blind. Two other groups of gastropods live at the surface of the ocean and, like Janthina, live an upside down existence. These are the tiny brown Litiopa snails which adhere to floating sargassum seaweed by means of a silken thread of mucus, and the heteropods or fin-footed sea snails which remain afloat by paddling a wide, fin-shaped foot. The latter group includes the rare and highly prized Carinaria, the Atlanta shells and the shell-less Firoloida. Not all pelagic mollusks live solely at the surface. The transparent, delicate-shelled sea butterflies or pteropods (pronounced tero-pods) remain several fathoms below the surface during the daylight hours but move up- ward toward the surface at night. In many equatorial areas pteropods exist in great numbers, and the steady rain of the sinking shells of the dead mol- lusks litter the ocean’s bottom many feet deep. Among the sea slugs, one species of nudibranch (Scyllaea) is always pelagic, while the small and beau- tiful Bat Sea Slug, Gastropteron rubrum, makes nocturnal trips from the bottom of the shallow bay to the surface. The two pancake-shaped lobes of 18 American Seashells the foot of this snail are flapped up and down much in the manner of a bat in flight. However, the pelagic habitat and the ability to swim are the exception among the snails. The intertidal zone which is intermittently flooded and drained by the moving tides is well stocked with many kinds of creeping snails. Many Nassarius Mud Snails live exclusively on the warm, flat mud- Figure 3. a, The Nassa Mud Snail, Nassarius, crawling under the sand with its siphon extended into the water above; b, cutaway view of a prosobranch snail showing the direction of water currents (arrows) down the siphon, over the gills and out from the right side of the body. (After Ankel 1936.) bars of quiet bays. Among the carnivorous snails, we find that their ecologic stations are determined by the location of the worms or bivalves upon which they feed. One or two species of Terebra and Polinices Moon Shell are found burrowing in the sand of beach slopes where they are able to find their favor- ite clams, but the majority of these snail genera are found from low-tide mark to a depth of several fathoms. Since most marine gastropods are nocturnal in habit and shun bright sunlight, many species spend their time hidden in crev- ices under rocks. This affords protection to themselves and their eggs from predators, bright sun and violent wave action. A great number of species live in deep water, and frequently their verti- cal distribution is limited to relatively narrow ranges. From some 500 dredg- ing samples taken off southeastern Florida by the late J. B. Henderson’s yacht “Eolis,” Bayer’s Dwarf Olive (Olivella bayeri) was found in depths ranging from 25 to 115 fathoms. On the other hand, the Greenland Moon Shell has been found from twelve feet to over two miles in depth. In their experimental search for new living places, a few gastropods have evolved strange associations with other marine animals. The dwarf Cypho- Life of the Snails 19 ma (Simnia) lives on the latticed blades of seafans, while the root-like bases of the same seafans may be honeycombed with pockets of the Coralliophila shells. Some species of Trivia cowries not only live with the compound as- cidians or sea squirts (Botryllus) but also feed upon them. Deep holes are eaten into the ascidian in which the female snail deposits her flask-shaped egg capsules (fig. 9). Among the Ewlima and tiny Pyram snails there are many species which parasitize sea urchins and certain kinds of clams. Several spe- cies of Stylifer live embedded in the flesh of starfish, and only a wart-like Ficure 4. Three stages of parasitism. a, the Pyram Snails, Brachystomia, make daily visits to tap the body fluids of the mussel, Mytilus; b, the adult of the Stylifer Snail becomes encased in the tissues of the starfish; e, the Evtocolax Snail is embedded in the flesh of a holothurian sea-cucumber and has lost shell, oper- culum and mouth parts. swelling and a bit of shell spire projecting above the surface reveal their pres- ence. One species of Eulima lives inside the intestinal tract of the sea cucum- ber and obtains its food by tapping the nutritious juices of its host by means of a modified, syringe-like snout. HOW THEY GROW In most cases the shell material in the snails is secreted by special glands located along the edge of the fleshy mantle of the animal. Within the aper- ture or mouth of the shell a certain amount of reinforcing material may be secreted by the roof of the mantle, especially in the case of the heavy trochid shells which are nacreous within the aperture. The foot is often the source of shell material, not only as the site of the formation of the hard trapdoors or opercula of the turban and natica shells but also as an important addition to the shell itself. The actual formation of calctum carbonate and the forma- tion of the various layers are discussed in more detail in the chapter on clams. In some groups of gastropods, particularly certain wentletraps and liotias, the mantle edge is capable of producing exquisitely fine filigree or porous shell structure whose intricate designs and overlapping layers can best be seen with the aid of a magnifying glass. In the cowrie shells, the mantle has two large extensions which are spread at will over the entire outside of the 20 American Seashells shell. This covering mantle continually adds thin paintings of shell material over the entire outer surface of the adult shell. In these groups, where the outside of the shell is protected by the mantle, there is no production of pro- tective, horny periostracum. This is a tough, mat-like and often hairy cover- ing to the shell which prevents acids and marine growths from doing damage. FicurE 5. Four stages in the growth of the Keyhole Limpet, Fissurella, showing how the spire gradually disappears and the marginal slit becomes an apical hole. a, b, c, highly magnified; d, natural size. (After Boutan 1886.) In contrast to the bivalves, many gastropods exhibit certain modified shell structures when they become reproductively mature. In many instances adulthood of an individual is accompanied by the formation of a thickened or flaring apertural lip. It is most pronounced in the Strombus conchs, Peli- can’s Foot (Aporrhais), marginellas, cowries and others. Such development is unknown in the cone shells, Busycon whelks, abalones and a host of others. Growth of the gastropod shell is more rapid in young individuals. Some species apparently continue to grow in size during their entire life span, while others cease once sexual maturity is reached. In the murex shells and frog shells (Cymatium) and certain Cassis helmet shells a strong varix or thick- ened rib may be formed at the edge of the shell lip at regular intervals regard- less of sexual or seasonal conditions. Each thick varix represents a resting period in growth. Collectors may have noticed that they seldom find murex shells in a growth stage between varices. This is because over ninety percent of the snail’s life is spent in the varix stage and because additional growth between varices takes place in less than two days. The color pattern of shells is a graphic representation in time of the secretory activity of the pigment-producing cells located along the mantle edge. The ground color is produced by the whole line of cells; banding is produced by the special activity of groups of cells, often sharply localized. Where the activity of these groups is cyclical, blotching results; where the active focus moves up and down the mantle edge, or where activity spreads from a focus, there may be formed zigzag, V-shaped or circle patterns. A Life of the Snails 21 review of the biochemistry of shell pigments has been made by Alex Com- fort (1951). Rate of growth and span of life in gastropods vary according to the species and ecologic conditions. The maximum age of marine species is very imperfectly known. Undoubtedly many species live for only two, three or four years. The common European periwinkle (Littorina littorea) found in New England has been kept alive in captivity for twenty years. Large speci- mens of the Horse Conch, the Queen Conch (Strombus gigas) and the Cameo King Conch (Cassis) probably represent ten to twenty-five years of growth. The nudibranch sea slugs are believed to be short-lived, and Aeolis and Goniodoris have been shown to survive only into the second year. It is quite likely, though, that the Aplysia seahares and the Bulla Bubble Shells live for at least five years. The ultimate size of individuals in species in which the sexes are sepa- rate may be influenced by the sex of the individual. In many groups, such as the buccinid and Busycon Whelks, the Strombus conchs, periwinkles and others, the shells of the females are always considerably larger. In the Pale Lacuna Periwinkle (Lacuna pallidula), the females are from five to ten times as large as the males. ; Considerable variation in size results from the diet of mollusks. It has been experimentally shown that the Oyster Drill snails (Urosalpinx cinerea) eating Mya clam and oyster meat show the greatest increase in growth, while those feeding on barnacles and Mytilus mussels show the least amount of growth. It has also been found that snails of this species living in brackish water grow to a larger size than those living in pure sea water. Colonies of snails exhibiting these ecologic characters have been erroneously considered new species by some workers. HOW THEY FEED The gastropods are much more imaginative in their selection and man- ner of acquiring food than the bivalves and other mollusks. Unlike the clams, most snails travel in search of their food. A great proportion of the marine gastropods are carnivorous, but some are detritus feeders, others are vegetarians, and a few, like their bivalve relatives, are suspension feeders. Among the flesh-eating snails, there have been many modifications in the structure of the mouth parts, including the proboscis and the teeth. In some the snout has remained very simple, and the snail merely pushes the end of its mouth against its food and tears off bits with the tongue-like radula or row of teeth. But in others a remarkably long, tube-like extension is devel- oped which, when not in use, is retracted within the snout or head of the snail. When a living Melongena Crown Conch is quickly picked up, one can 22 American Seashells frequently see the three-inch-long, tubular proboscis being withdrawn into the snail’s head. This indicates that a clam or worm, upon which the snail was feeding, is located at that spot one or two inches below the surface of the mud. Figure 6. The open mouth of the Moon Snail, Natica, showing the radula ribbon and its teeth. X3. (Redrawn from Ankel 1936.) In the Natica Moon Shells, there is a muscular disk on the under surface near the end of this extensible proboscis, which serves as a suction disk while the radula is at work on the clam shell. No evidence of the presence of acid has been presented so far. Once the clam is perforated, the long proboscis is wiggled down into the flesh of the clam and the moon shell is able to remove most of the flesh without opening up the valves of the clam. Some Murex Snails and the Busycon Whelks open their clam victims by applying suction with the sole of the foot and by prying apart the valves with the edge of the outer lip of the shell. The large group of rachiglossate snails (those having three large teeth in each radular row) are for the most part predators. The Tun Shells and Cassis Helmet Shells feed upon live sea urchins. The Xancus Chanks, Busycon Whelks and others feed upon live clams. The Nassa Mud Snails, however, are purely scavengers, and their ability to detect the odor or taste of spoiled meat in the water is highly developed. Among the toxoglossate snails (those with tiny, needle-like, harpoon-shaped teeth as shown in figure 1), the cones and Terebra shells have a highly developed poison gland and duct which are presumably used in quieting their prey. Vegetarians are found among the more primitive gastropods. All of the limpets, nerites, trochids and turban snails graze on seaweeds. However, many of the “middle-class” snails, among them the ceriths, Modulus, and some periwinkles, limit their feeding to swallowing mud detritus on the bottom Life of the Snails 23 from which they obtain small algal cells and diatoms. The common Atlantic Slipper Shell feeds in the same manner as the oyster, and its stomach is found to contain the same diatomaceous food. Just as in the oyster, a food current of water is set up in the mantle cavity and the pectinate gill acts as a food sieve. Ihe food particles are entrapped on the gills by a mucus secreted by an endostyle which is located at the base of the gill. Tiny cilia move the food along a groove on the side of the body to a pouch located near the mouth where it is then taken in up through the proboscis. Twrritella com- munis of Europe buries itself in mud and has a ciliary feeding habit. This snail remains for days in one spot just below the surface of the mud. An inhalant depression in the mud is made by lateral movements of the foot, and the action of thousands of cilia creates a current which brings food-laden water into the mantle cavity. There is a unique exhalant siphon constituted by two overlapping folds, and through this are expelled water and fecal pellets without disturbing the surrounding mud. The most extreme modifications in the entire molluscan phylum have occurred in connection with the feeding habits of certain parasitic snails. For years the Entoconcha snails found inside the Synapta sea cucumbers were thought to be some form of parasitic worm. The “head” of the mollusk is attached in leech-like fashion to a blood vessel of the host, and its worm-like body is embedded in the gonads of the sea cucumber. The adult parasite has no shell, sensory organs, nervous system or radula. It is little more than a tube adapted to absorbing the blood of the host and carrying on self-fertili- zation. Were it not for the tiny young found inside the adult with their small shell and operculum, it is doubtful if these creatures would ever have been thought to be mollusks. The passage of food from the buccal cavity, through the esophagus to the stomach is facilitated by muscular contractions of the wall of the alimen- tary tract and by saliva produced by the two salivary glands. The hind end of the esophagus may be modified into a gizzard, and in many Bubble Shells, especially Scaphander, there are several large, cucumber-shaped plates armed with hard corrugations which grind the food into small particles. The stom- ach proper consists of a simple enlargement of the digestive canal. Its wall may be smooth, furrowed, or lined with spines. As in most bivalves, some snails possess a jelly-like crystalline style which projects into one corner of the stomach and dissolves off digestive enzymes. The so-called “liver” of the snail which forms most of the upper part of the soft, coiled viscera is actually a digestive gland where food material is broken down and absorbed into the blood stream. 24 American Seashells HOW THEY BREATHE Breathing by most aquatic marine snails takes place through the gills where oxygen is obtained from the sea water and where the waste gases are dissolved. The numerous gill leaflets are usually located on the inner side of the mantle. Except in the primitive snails with a pair of gills, water is brought into the mantle cavity through the siphonal canal or through the region to the left of the head. It then bathes the gills and passes out on the right side of the body. The current of water is maintained by thousands of microscopic, lashing, hair-like cilia mostly on the gill leaflets. Like the bivalves, the snails display a wide variety of types of gills. The most primitive groups, such as some of the Keyhole Limpets, Slit-shells, Pleurotomarias and abalones have two pairs of gills. They are of equal size in the Keyhole Limpets, but in some others the right one is considerably smaller. In the higher groups of snails, the left gill is the only one remaining. In the Cerithidea snails, the gills are reduced to mere stumps, and respiration takes place in the mantle skin itself. The sea slugs have lost their ctenidia but have evolved very complicated and beautiful gill-like organs on the sides and back of their bodies. Many of these gills have taken on the shape of miniature shrubs and trees. HOW THEY REPRODUCE The subject of reproduction among the gastropods is a fascinating study of many important phases of biology. Our final concepts of the formation of species, our understanding of zoogeography, distributional methods and the basis of sex determination are dependent on a fuller knowledge of reproduc- tion. The manner of assuring fertilization of eggs, the various methods of egg-laying and brooding of young and the interesting types of larval devel- opment are horizons of research that are now being expanded. The gastropods exhibit nearly every possible modification of sexuality. Two of the three orders of snails, the opisthobranchs containing the sea slugs and the land snail pulmonates, combine a complete set of male and female organs in the same individual. The gonad produces both sperm and eggs, but there are separate ducts for the products of each sex. Despite the dual sex life, all mature individuals experience the mating instincts of both sexes, and during copulation there is a mutual exchange of sperm. In some sea slugs, the tectibranchs, several individuals may form rows or a ring of copu- lating snails. In some fresh-water pulmonates, self-fertilization is sometimes practiced, and some experimenters have bred over ninety generations, extend- ing over twenty years, without cross-fertilization between individuals. The marine gastropods contain representatives of several categories of Life of the Snails 25 sexuality. Dual sexuality or hermaphroditism as found in the pulmonates is also known in some species of Acmaea Limpets, Janthina, Odostomia, Stilifer, Valvata and the Paper Moon Snail, Velutina. The sexuality of this type, however, is more of the consecutive type, in which the gonads at first pro- duce sperm and later in the season only eggs. Sex reversal is especially characteristic of the Slipper Shell family. The best known examples belong to the Cup-and-saucer Shells, Calyptraea and Crucibulum, and the true Slipper Shells, Crepidula. Individuals function as Ficure 7. Sex reversal in the Slipper Shells, Crepidula. a to e, animal with shell re- moved to show the development of the verge in the male phase; f and g, atrophy of the verge and the change to the female phase; h, a group of attached Crepidula fornicata, showing the smaller males ( é ) at the top and the females ( ¢ ) below; i, Crucibulum spinosum with the small male attached to the female. (After W. R. Coe 1943.) the male sex when young and as females when fully grown. The change-over may be gradual with the individual being ambisexual for a short period, or the male phase may suddenly disappear with the loss of its associated organs, and the female organs may then quickly develop. The males are much smaller than the females. In most species, each young male tends to creep about until it finds an individual of the same species in the female phase, whereupon it attaches itself to the dorsal side of the female’s shell in a posi- tion adjacent to the female copulatory organs (fig. 71). In other species the 26 American Seashells ZF py & VPS B. CONTRARIUM y NEPTUNEA F TULIPA F HUNTERIA PLEUROPLOCA GIGANTEA — CONUS MUS EPITONIUM UROSALPINX CINEREA COLUMBELLA Ficure 8. Gastropod egg cases. Life of the Snails x40 LITTORINA LITTOREA LITTORINA ZiczaAc ae Sea, Sane TECTARIUS MURICATUS TRIVIA {mm. CANCELLARIA APLYSIA NASSARIUS Ficure 9. Gastropod egg cases. 28 American Seashells males usually occupy positions in the vicinity of the female and move to the mating position at night. Occasionally bachelors are found which either by chance or choice remain solitary throughout the entire male phase. Soon after hatching from the egg, and in one species (Crepidula adunca Sowerby from Panama) even before hatching, a slender copulatory organ, the verge or phallus, grows out from the body behind the right tentacle (fig. 7). As the female phase develops later in life, the verge begins to shrink and is finally absorbed as the female organs take form. Associated with these changes is a marked alteration in behavior, whereby the wandering individ- ual, which was so characteristically masculine when young, now becomes strictly sedentary. She receives her mate, lays her eggs in capsules beneath her foot and broods her young until they are prepared for their own inde- pendence. In our Common Slipper Shell, Crepidula fornicata, those individuals which live on muddy bottoms where there are no solid objects to which they can attach themselves, frequently pile up in groups of six to twelve or more. These groups continue from year to year, newly arrived young in the male phase attaching themselves to the top of the pile as the old, female- phase individuals die at the bottom. Most marine prosobranchs, however, are of separate sexes (dioecious or unisexual). While some species in which the sex products of both sexes are discharged freely into the water have no outward morphological features, there are a great number of gastropods in which the male has an external copulatory organ or verge. The shape and position of the verge are often used in classifying families, genera or species. Depending upon the species, and sometimes the genus, the females take care of their young in a variety of ways. In some there is no motherly instinct, and the eggs are liberated directly into the water where they float away on the chance of being fertilized by the free-swimming sperm from a nearby male. (See fig. 9 with Tectarius and Littorina.) In other types the eggs are fertilized and undergo development to the adult-like form in the uterine portion of the oviduct. Others have developed a kangeroo-like pouch in the tissues of their back where the young are allowed to develop to the adult form. Once liberated, however, the young do not return to the pouch. Viviparity or the giving birth to young alive (technically ovoviviparity) is known in Planaxis, Littorina saxatilis and a number of fresh-water species in several different families. THE Ecc Cases oF SNAILS Among a large proportion of the marine gastropods, the females form special egg cases or capsules into which the eggs are placed, and where the Life of the Snails 29 eggs may develop in an undisturbed, food-laden medium. Very frequently extra eggs (nurse eggs) are added which serve as food for the young that hatch first. The young may emerge from the egg cases as miniature replicas of their parents and commence a life of crawling and feeding, or they may escape as free-swimming larval forms. The latter are known as veligers and possess special organs for swimming. The larval shell is often quite different from the adult shell and, in some species, there may be an extra shell or echinospira encasing the entire veliger. There are many types of egg cases, and some of these are illustrated in figures 8 and 9; others are briefly described under the generic or family discussions in the identification section. Several types of egg-laying may be found within a single family or even genus. 1. Eggs Laid in Capsules and Attached to the Bottom: Rissoidae, Caecum, Epitonium, Thais, Murex, Colus, Neptunea, Busy- con, Buccinum, Melongena, Nassarius, Bela, Mangelia, Voluta, Conus, Co- lumbella, Fusinus, Cancellaria, Marginella, Neritidae and others. Of these, some have nonpelagic development: some Murex, Conus, Natica and most Marginella; others have pelagic, free-swimming young: Nerita, some Murex, some Conus and some Natica. 2. Eggs Laid in Gelatinous Masses or Strings: Acmaea, Gibbula, Fissurella, Lacuna, Littorina obtusata, some Turri- tella, Bittium, Triphora, Cerithium, Capulus, Strombus, Aporrhais, Cassis, all opisthobranchs and heteropods. 3. Eggs Laid in Capsules and Protected by the Female: Crepidula, Caly ptraea, Janthina, Cy praea, Hipponix, V ermetus. 4. Eggs Laid in Sandy Collars: Polinices and Natica. 5. Eggs Shed and Developing Suspended in Water: Some Acmaea, some Gibbula, Tectarius, some Littorina, Haliotis, and the heteropods, Atlanta and Oxygyrus. In some groups of snails which are more or less sedentary, the egg cap- sules may be protected by the female. In the cap-shell, Hipponix, the under- side of the foot of the female has a tough, reinforced ridge of flesh to which she attaches her gelatinous egg sacs. In some worm-shells, Vermetus, whose shells are permanently attached to the rocks, the eggs are deposited on the inside of the female’s own shell. The time and length of breeding differs among mollusks depending mainly on the geographical locality, the temperature of the water, phases of the moon and the inherent characteristics of the species. Some species spawn once a year for a few weeks only, while others may produce eggs half of the year as long as the temperature is suitable. The eggs, larvae and young have been described for many species by 30 American Seashells famous workers such as Gunnar Thorson, Marie Lebour and others. The common European Periwinkle (Littorima littorea) will serve here as an ideal example of the pelagic type of development. The female spawns two to twelve hours after copulation by the male. About 200 single egg capsules are shed during the night. During the entire breeding season of six months, the total number of egg capsules per female is estimated at about 5000, and a half dozen copulations are necessary to ensure fertilization of all the eggs. The helmet-shaped capsules are shed freely and float about in the water. Each contains from one to nine eggs. The free-swimming young, called veligers, hatch on the sixth day and remain afloat for two weeks or more, depending upon temperature conditions, then sink to the bottom and begin an adult snail’s life of crawling. They reach maturity on the second or third year and may live for five to ten years. In contrast to this mode of spawning, the Left-handed Whelk of Florida (Busycon contrarium) \ays its horny strings of egg capsules during a rela- tively short period of a few weeks. On the west coast of Florida egg-laying usually takes place in the spring. The female digs down well below the surface of the sand and attaches the first few capsules to a buried rock or broken shell. As the process of extrusion of the egg capsules continues, the female moves toward the surface until its siphon can protrude into the water to allow easy respiration. As more capsules are made, the string may loop out into the water above the hidden adult. From five to fifteen cases may be formed each day, and a completed two-foot-long string may have nearly a hundred capsules. Within each case there may be two to twenty-five eggs which in a few weeks will develop to quarter-inch-long young. These minia- ture replicas of the adults eat their way out of the case at a special “door” and commence crawling and feeding immediately. The Left-handed Whelk begins spawning at a relatively early age, commonly when no larger than three inches. In such cases the capsules are only a half inch in diameter, while larger females may produce capsules about the size of a half dollar. CHAPTER Lil Life of the Clams OF THE approximate 15,000 species of existing clams or bivalves, four fifths live in the sea, while the remainder are inhabitants of fresh-water rivers, lakes and ponds. Throughout the seventy or so families of this class, the clams show an amazing diversity of ways of adapting themselves to almost every kind of aquatic environment. There are clams that swim, burrow, dangle by silken threads, others that are permanently cemented to rocks and corals, some that live a sedentary life of attachment to other marine creatures. In size, they vary from the 500-pound giant Tridacna clams of the East Indies, which reach a length of over four feet, to the pinhead-sized Amethyst Gem Shells (Gemma), which so heavily populate some of our intertidal flats. In ornamentation and coloration the clams are almost unexcelled in their wide range of beautiful hues and bizarre shapes. WHERE THEY LIVE The bivalves have selected a wide variety of ecological stations in life. While many must live in strictly marine waters, a few have adapted them- selves to the brackish waters and estuaries and inland bays. One species, the Coon Oyster of Florida and the West Indies, has “taken to the trees” and is able to withstand exposure to the air for several hours, or even days, between high tides. In its early, free-swimming stages, the oyster is carried by the rising tide in among the roots, trunks and overhanging boughs of the mangrove trees where it settles and attaches itself. Feeding, growth and reproductive activities take place only during the few short hours of high 31 32 American Seashells tide. The Coquina Clam, Donax, is faced with much the same problem of making the most of high tides but, in contrast to the sedentary life of its oyster cousin, it leads a very active existence on the sandy beaches along the open ocean. It is an attractive sight when a scouring wave suddenly studs the white beach with dozens of brightly hued clams. The tumbling motion and sudden exposure to light act as a stimulus to the clam which instantly thrusts out its small muscular foot and rapidly pulls itself down into the sand again. During the three or four hours in which the waves are sweeping the middle and upper sections of the beach, the tiny clams may be uncovered and obliged to burrow down again several hundred times. While many clams prefer clean sand as a habitat, others are habitual mud-dwellers. The handsome Angel Wing, Barnea costata, is usually found in mud so soft and deep that Florida collectors find it extremely difficult to reach them. The Angel Wing is usually located one or two feet below the mud surface and maintains its connection with the bay’s waters with its long siphon. Because of its popularity as a souvenir and collector’s item, methods have been devised to collect them at high tide from a boat or barge. Power- ful jets of water are forced through hoses, the mud is swept away from the clams, and then hand-nets are employed to gather them. In more shallow regions where a mixture of sand in the bay bottom permits walking, the exposed Angel Wings are gathered by hand at the next low tide. The majority of marine clams live in a substrate of sandy mud, but a few have become specialized to the extent of making burrows in exceedingly compact clay, as in the case of the Arctic Saxicave, Hiatella arctica, and the False Angel Wing, Petricola. A few groups such as the Date Mussels, Lithophaga, and the Piddocks, Pholas, burrow into corals, other shells or soft rocks such as sandstone and limestone. The shipworms, Teredo and Bankia, are expert at drilling out their long, tube-like homes in wooden planks of ships, wharf pilings, and manila hemp. So too is the Wood Piddock or Martesia. A large proportion of bivalves are found in shallow water, but many others are typically deep-water dwellers. The bathymetric range for some species may be narrowly defined in the case of certain scallops, Dipper Clams (Cuspidaria) and astartes. On the other hand, some species found in a few feet of water may also occur in depths of over two miles. One species of Abra Clam, Abra profundorum E. A. Smith, has been dredged in the mid-North Pacific at a depth of 2,900 fathoms—over three miles! HOW THEY GROW The shelly valves of clams are the product of the fleshy mantle. This thin, leaf-like organ covers the animal as the flyleaves cover the body of a Life of the Clams 33 book and, by its physiological activities, secretes the hard valves of calcium carbonate, which thus come to occupy the position of the covers of the book. In the simplest form of mantle the edges are free except on the back, where the hinge of the shell is located, corresponding to the arrangement of a book. Sea water may enter the cavity enclosed by the mantle at almost any place. In many groups of bivalves, however, the mantle edges may be fused, not only along the back where the valves are joined together but along all or most of the lower margins. Openings are usually present to accommodate the foot and siphons when such organs are developed. PERIOSTRACUM OUTER LAYER Mipple LAYER INNER LAYER & INNER LAYER PERIOSTRACUM b Figure 10. Structure and layers of a clam shell (Tellina tenuis). a, Diagrammatic representation of a small piece of shell; b, Cross-section of shell showing the loose end of periostracum around the margin of the shell. (After Trueman 1942.) From its food supply the clam absorbs minerals into its blood system which are then carried to the mantle. A certain amount of shell deposition takes place along the thickened borders of the mantle, although a small amount, including pearly or nacreous material in some species, is laid down by other parts of this organ. The liquid secretion of lime salts becomes crystallized when mixed in a colloidal albumen which is also produced by the mantle. Several types of shelly material are laid down in definite layers, and the structure and composition may vary depending upon the family or genus of mollusks. The structure of a layer may be prismatic (made up of tiny, individual, closely packed prisms), foliated (layers built up of over- lapping leaves), macreous (mother-of-pearl), granular (like grains of sugar stuck together), crossed lamellar (a common type in which the long lamellae are rectangular), or it may be homogeneous with no visible structure. The mineral character of these layers may be calcite (2.7 times as heavy as water) or aragonite (2.9 times as heavy as water), both of which are forms of calcium carbonate. The shell of the tellin clam (Tellina), for instance, is made up of three layers of calcium carbonate and the horny periostracum. The latter con- 34 American Seashells sists of a very thin layer of conchiolin, probably not more than 0.003 mm. in thickness. In other clams, such as Arca, it may be many times as thick. It is normally secreted from a group of cells situated just under the tip of the mantle. The three shell layers are: (1) The outer layer of shell which consists of elongate radial prisms of calcite. These are arranged in concen- tric bands which are plainly visible on the outer surface of the shell. (2) The middle layer which is entirely composed of aragonite in the form of “crossed lamella.” ‘This specialized structure is peculiar to mollusks. (3) The inner layer which is a homogeneous layer of porcellaneous material. The Pen Shells of the genus Pimna commonly found on the west coast beaches of Florida offer an excellent demonstration of prismatic structure. When the surface is examined with a high-powered lens, it appears to be honeycombed. What you see are the ends of the needle-like prisms of calcite which, although closely packed together, are separated from each other by a thin varnish of conchiolin. By examining the edge of the broken shell you can make out the prisms in side view. Most clams continue to grow in size during lifetime, but the greatest in- crease takes place during the first year or two. A species may show con- siderable variation in its manner of growth under different living conditions at various localities. Thus the Pacific Razor Clam (Siliqua patula) in its southern range in California grows much faster and reaches a length of about five inches in three years. In Alaska, however, it grows more slowly, taking five to eight years to reach the same size. Yet the northern colonies continue to grow for a greater length of time, some living for fifteen to eighteen years and eventually reaching a length of over six inches. This is also true of the Pacific Cockle (Clinocardium nuttalli) which in ten years grows to three inches in length in California, but in Alaska it survives six- teen years to reach a length of five inches. The maximum age is known for a few species of clams. It is believed that the giant Tridacna clam of the Indo-Pacific lives for perhaps a hundred years, but this has not been confirmed by experiments or accurate calcula- tions. The average age of the Atlantic Bay Scallop (Aequipecten irradians) is about sixteen months, its maximum age only two or three years. The average age of a five-inch Pismo Clam (Tivela stultorum) on the Pacific Coast is about eight years, its maximum age twenty-five years. The Com- mon Blue Mussel (Mytilus edulis) grows to about two inches the first year, to four inches the second year but, beyond this, it grows very little although it may live for a total of seven or eight years. The Soft Shell Clam (Mya arenaria) takes about five years to reach an edible size of three or four inches and may live for ten years. The Washington Clam (Saxidomus nuttalli) lives ten to fifteen years or longer, while Nuttall’s Gaper Clam (Schizothaerus nuttalli) may survive for seventeen years, Life of the Clams 35 HOW TREY PEED Normally one does not think of clams and oysters as being very active feeders and certainly, in comparison with the voracious methods of fish and squid, the bivalves are rather peaceful eaters. Yet in their characteristic way they are highly efficient and, in proportion to their size, possess a large and varied menu. Most clams feed on minute plants and, in a relatively short time, can filter from the sea water an extraordinary number of living diatoms and dinoflagellates—microscopic, swimming plants—and protozoa of the ocean. A few genera, such as the small Cuspidaria and Poromya clams, are carnivorous and feed upon small living or dead animals, usually crustaceans and annelid worms. Figure 11. Extended animals of some bivalves, showing various types of siphons. a, Mya arenaria Linné, b, Tellina agilis Stimpson; c, Tagelus plebeius Solander, d, Ensis directus Conrad. (From A. E. Verrill 1873.) The bivalves fall into two general classes of feeders—suspension feeders which merely pump water through their mantle cavity and thus obtain free- swimming or suspended creatures from the water; or deposit feeders which suck up food from the muddy bottom with their long, mobile inhalant si- phons. Among the suspension feeders are the oysters, scallops, venus clams, cockles, the shipworms and many others. They may or may not possess siphons, but when present these are generally short. The deposit feeders include such forms as Tellina, Macoma and Abra which all have long siphons. Whether food is taken in through the inhalant siphon as in the tellins or through a slit in the mantle as in the scallops, it must pass over the gills. These filament-like organs are covered by a thin sheet of mucus. Food passing through the gills becomes ensnarled in the mucus which 1s transported by water currents and myriads of tiny, hair-like cilia. Mucus is constantly be- 36 American Seashells ing secreted and carried to the food grooves bordering the gills, along which the food-laden strands are carried to the mouth. Our common Atlantic Oyster and those in France are frequently found with green gills. The “green oysters” of Marennes, France, are famous for their supposed medicinal qualities. Americans are inclined to shy from “green oysters,” because they fear the color may be a sign of spoilage. Oysters feeding upon the small diatom, Navicula ostrearia, digest these single- celled plants and absorb from them large quantities of blue pigment. In the tissues of the oyster’s gills the pigment appears in the form of a sickly but quite harmless green. Occasionally, however, our oysters may take on a general greenish tint, not due to diatoms but to an increase in the amount of copper in the tissues. Such oysters have a rather brassy taste. Figure 12. Siphons of bivalves projecting above the sand bottom. Mya (b) is a suspension feeder, the others deposit feeders. a, Tellina and Macoma; b, Mya; ¢, Gari; d, Donax; e, Trachycardium. (After C. M. Yonge 1949.) The clam has considerable choice in what it wishes to eat, and it can reject undesirable particles of sand or oversized pieces of food. The gills and the two fleshy palps, or flaps guarding the mouth, help in sorting out the right-sized organisms. Acceptable food is taken into the funnel-shaped mouth, passed through a short esophagus and enters the stomach. Inside the stomach, a further selection of food may take place with indigestible matter being passed on immediately through the intestine. The best food passes from the stomach into the digestive gland where it is broken down chemically and absorbed into the blood stream. TELLINA CHLAMYS MYTILU VOLSEL Ficurr 13. Fecal pellets of mollusks are characteristic in shape and may aid in identification of genera and species. (After H, B, Moore 1931.) Life of the Clams Bi Lying close to the stomach is a sac which contains a cucumber-shaped, jelly-like crystalline style. The end of this style projects into the stomach. It rotates clockwise and dissolves its enzymes in the stomach which aid in digesting the food, that is, in converting starch into sugar. The style, numer- ous cilia and the furrows on the stomach wall aid in churning the food. The fecal pellets of mollusks are often very distinctive for the various genera and species. Some are cylindrical rods, others elongated strings or ribbons, and a few consist of strands wrapped up in round balls. In cross- section, some rods are characteristically bi- or trilobed. Feeding is not done at all times, although a great part of a bivalve’s life is spent in securing food. The oyster, for instance, spends from seventeen to twenty hours of each 24-hour period in taking in water for the purpose of feeding and breathing. Individuals living in the intertidal zone and left dry by receding tides or exposed to water heavily charged with silt spend considerably less time feeding. During cold periods, when the water tempera- ture falls below 40° F, the oyster goes into a state of hibernation, and it ceases to feed because of the lack of coordination of the ciliary motion along the surface of the gills. Under ideal conditions, the Giant Pacific Oyster (Crassostrea gigas) filters 54% quarts of water per hour at 77° F (1 quart at 34° F). In a year, the total amount would fill a 10,o00-gallon tank car. Perhaps the most startling modification of obtaining food nutrients is exhibited in the giant Tridacna clams of the Indo-Pacific reefs. These clams literally “farm” colonies of brown-colored algal plants (Zooxanthellae) in their huge, exposed mantle edges. Unlike most clams, the Tridacnas spread their valves open and expose their mantles to as much sunlight as possible for the benefit of these single-celled seaweeds. In addition, small, fleshy tubercles grow on the surface of the mantle in which are located lens-like, clear cells. Sunlight can thus penetrate down into the flesh and be diffused into areas which otherwise would not receive enough light for the algae. Surplus plant cells are engulfed by phagocyte blood cells of the clam and transported to the digestive gland for absorption as food. The giant clams also feed in the conventional gill-to-mouth manner and are therefore not entirely dependent on the algae. The algae, however, must have a clam as a host in order to survive. This peculiar symbiosis is found to a lesser extent in the Bear Paw Clam (Hippopus), the Heart Cockle (Corculum) and the nudibranch, Phestilla. This phenomenon is not to be confused with the pathologic entry of the parasitic blue-green algae in fresh-water mussels, Anodonta and Unio. While the gills are the main organs for catching, sorting and transporting food in the majority of clams, they are limited to respiratory functions in a few groups. The smallest and most inefficient gills are found in the primi- tive protobranchs (Nucula, Nuculana, etc.) and in the small, highly evolved 38 American Seashells septibranch clams (Poromya and Cuspidaria). In order to make up for the loss of efficient food-gathering gills, the palps near the mouth have become Figure 14. The pair of proboscides in the Nut Clams, Nucula, sweep up food and transport it to the mouth. The gills are not used in gathering food as in the majority of clams. a, X5; b and ec, ends of the proboscides. X10, (After K. Hirasaka 1927.) very specialized. In the Nucula Nut Clams, a pair of strong, muscular, con- tractile organs serve as food gatherers. These proboscides are very flexible, moving about freely in all directions. Food material is picked up by the tip and is carried swiftly down a large groove in the proboscis to a palp pouch and then to the stomach by means of minute cilia. E. S. Morse very aptly described the action of these appendages in our Atlantic Nut Clam, Nucula proxima: Without seeing the behaviour of these appendages it is difficult to appre- ciate the remarkable action of these feeding organs. The graceful move- ments of these beautiful and translucent appendages, exceeding the length of the shell, sweeping rapidly the bottom of the dish in which they are confined, or even turned back and feeding on the surface of the shell, are a most curious and interesting sight. HOW THEY BREATHE Oddly enough, the gills of the bivalves are not primarily used for respira- tion, despite their conspicuous size. As has been noted, their main function is in connection with feeding. Some experts deny their role as respiratory organs entirely, claiming that the mantle with its extremely effective blood supply serves as the main place of oxygen and carbon dioxide exchange. It has been found that blood coming from the mantle to the heart is com- pletely charged with oxygen received from the sea water. Undoubtedly, however, the gills do absorb oxygen to some extent. Indirectly, the gills are extremely useful in respiration, since they produce the all-important currents which bring in oxygen and remove carbon dioxide dissolved in the water. Life of the Clams 39 A certain amount of respiration may take place even when the valves of certain bivalves are completely shut during exposure to dryness or to heat from the sun. What little air may be trapped within the mantle cavity of the animal is soon used up. Oxygen is then obtained anerobically (with- out contact with air) by cleavage of reserve glycogen substances stored in the clam’s tissues. Carbon dioxide builds up and is dissolved in the fluid in the mantle cavity, and the resulting increase in acidity may dissolve or etch away portions of the shell. Shells of oysters and the Patella limpets which are kept dry on the rocky coast for unusually long periods show considerable etching on the inside. Shells of the Date Mussels (Lithophaga), which live in a small volume of water in their rock burrows, are etched in this manner, while those specimens which live in the same volume of well- aerated water are not etched. Bivalves can be forced to cease respiration for several days without succumbing, but they are very susceptible to polluted waters and excess amounts of silt. The “‘red tide” caused severe destruction to the marine fauna on the west coast of Florida in 1946, and for several years afterward the “shelling” on famous Sanibel Island was little better than it is on Coney Island Beach, New York. ‘Red tides” have occurred from time to time in California, Washington State, Japan, Australia and elsewhere. They are caused by an unusual increase in the numbers of single-celled dinoflagellates, Gony- aulax. It is believed that billions of these organisms not only deplete the oxygen supply but also clog the gills of fish, mollusks and other animals which die in vast numbers and further befoul the ocean. Fortunately, these “red tides” spend themselves out, and the coastal waters return to normal in a few years. Another species of Gonyaulax (G. catanella) may be ingested by mus- sels and clams and, although it does no harm to the mollusk, it is highly toxic to humans who may eat the infected shellfish. A number of deaths have occurred on both of our coasts from this type of mussel poisoning. There is no way of distinguishing poisonous from sound mussels by their appear- ance, and heat does not destroy the poison. Mussel poisoning occurs along the California coast from May 15 to October 15. There is another such center in Nova Scotia. Among the various schemes of classification of the bivalves, the type of gill structure has been used by many students of phylogeny (the study of molluscan ancestral trees), such as Lankester, Pelseneer, Ridewood and others. Opponents to this system, such as Neumayr, Munier-Chalmas, Dall, Cotton and others, have based their classification on the hinges of the shell valves. Neither system is without its weaknesses, and in some modern schemes the two systems are employed together. There are four main types of gills: (1) Protobranch, in which the gills 40 American Seashells are flat, plate-like, unreflected lamellae and are regarded as the most primi- tive (Nucula, Yoldia, etc.); (2) Filibranch, in which the gills are long curtains folded back against themselves and held close to each other by the Gi GILL SEPTUM PLATES FILAMENTS FOOT a d Figure 15. Diagrammatic cross-sections of clams showing the major types of gill structure. a, protobranch,; b, filibranch; c, eulamellibranch, d, septibranch. interlocking of the tiny cilia on the surface of the gill filaments (arks, mus- sels, scallops, etc.); (3) Eulamellibranch, similar to the filibranchs except that the gill curtains are united by cross-channels (astartes, cardiums, venus clams, tellins and many others); (4) Septibranch, which have very degenerate gill structures consisting of two pallial chambers with only gill slits or very reduced gill filaments acting as windows to the chambers (Cuspidaria and Poromya). HOW THEY REPRODUCE The staid bivalve has made his share of contributions to experiments in sex and reproduction, and throughout the class we find varying degrees of sexual differentiation, as well as all manner of ways of insuring proper fertili- zation, protection of the young and thus the continuation of the species. The pelecypods have no copulatory organs or other external sexual characteristics, with the exception that in certain species of fresh-water mussels, the marine astartes and a few other genera, the two sexes can be distinguished by the shape of the adult shell. The majority of the bivalves as a group are predominantly of separate sexes, but at least four percent of those adequately studied are known to deviate from the strictly dioecious, or unisexual, condition. A few species are true hermaphrodites in which the same individual contains both female and male sex organs which may produce eggs and sperm simultaneously. In this group are found certain species of Pecten, Tridacna (the Giant Pacific Clam), Kellia, Dinocardium, Gemma, Tivela (the Pismo Clam), Thracia, Poromya, the shipworm Teredo diegensis and the fresh-water genera Anodonta, Pisidium and Sphaerium. In some of these Life of the Clams 41 the eggs are fertilized within the mantle cavity, and the young complete development to the adult form in brood pouches on the gills of the parent. Usually self-fertilization does not occur, for in the majority of these species the sperm is discharged before the eggs are mature in the same individual (protandric hermaphroditism). Other kinds of bivalves are accustomed to practicing sex reversal in which the early part of their lives is spent as males and their “adulthood” as females. In the Quahog (Mercenaria mercenaria), nearly all individuals experience a male phase in which functional sperm is produced while the clam is only a few months old. Following this initial male phase, about half of the population turns female to produce eggs, while the other half remains male. No further sex change takes place. Sex reversal is apparently very popular among some of the oysters, such as our native Pacific Coast Ostrea Jurida. In this species there is a series of male and female phases. There may be three changes within a single year. Usually the male phase comes on first. Alternating sexuality also occurs in our Atlantic Oyster (Crassostrea virginica), but the early sex organs are capable of turning toward either male- or femaleness. It is not known, at present, to what extent environmental conditions determine the direction of sex change. It has been shown, however, that under unfavorable circum- stances, when circulation of water is poor and the food supply low, there are more female oysters in a colony. When conditions improve, the percentage of males increases considerably. Thorough studies have now been made to show that normally no sex reversal occurs and that the sexes are separate and of equal numbers in a given colony in the following species: Modiolus demissus, Mytilus californi- anus, Septifer bifurcatus, Anomia simplex, Mytilus edulis, Petricola pholadi- formis, Donax gouldi, Mya arenaria (Soft-shell Clam) and the Angel Wing, Barnea costata. The number of eggs produced by the female bivalve may vary consider- ably depending upon the species and environmental conditions. Species which retain the fertilized eggs within their bodies for further development invariably produce fewer eggs than those species which discharge them into the water. The oysters are probably among the greatest molluscan producers of eggs. C. R. Elsey estimates that one female Crassostrea gigas of Japan and our northwest Pacific Coast may discharge into the water each year eggs numbering 1000 to the eighth power. If all survived in five generations, the aggregate would be large enough to make eight worlds like ours. Need- less to say, enemies and unfavorable conditions kill off most of the young. In contrast to this prodigious effort on the part of the oyster, the Dwarf Turton Clam (Turtonia minuta) deposits only 12 to 20 eggs which are neatly encased in oval egg masses of gelatinous material. While most species 42 American Seashells of Nucula Nut Clams discharge their eggs freely into the water, one New England species, N. delphinodonta, deposits from 20 to 70 tiny, opaque brown eggs in a gelatinous sac which is attached to the posterior end of the valves of the shell. Small bits of debris and mud stick to the outside of this sac, which probably serve as a camouflage. Many bivalves keep the develop- ing young within the mantle cavity or in the meshes of the gills until the tiny shells are quite well advanced in development. With the aid of a high- powered lens one may readily see tiny juvenile clams inside the translucent adult shells of such genera as Gemma, Parastarte, Psephidia, Transennella, Kellia, Lepton and Lasaea. The odd Dwarf Milner Clam of California (Mil- neria minima) incubates about 50 young in a peculiar external pouch. The valves are indented on the ventral margins to form a neat exterior pocket. To prevent the young from dropping out, a sheath of periostracum is stretched over the entrance. When the small clam shells have grown sufh- ciently to fend for themselves, the sheath is “unzipped,” and all tumble out into the free world. TTT LTE Figure 16. The LL Bankia gouldi, in the act of ae its neighbor. The spotted siphons are shown projecting from the wood in which these bivalves live. Arrows indicate the direction of water currents. X5. (Redrawn from W. F. Clapp 1951.) In practically all cases, the sperm from bivalves is liberated into the water where it comes in contact with unfertilized eggs that have been pre- viously released. In cases where eggs are retained by females, the sperm is sucked in through the inhalant siphon of the mother. Only one instance of pseudo-copulation is known. In 1951 workers at the W. F. Clapp Labora- tories observed Gould’s Shipworm (Teredo) placing their exhalant siphons down into their neighbors’ inhalant siphons and discharging what is pre- sumed to have been sperm. Life of the Clams 43 HOW THEY SENSE AND SEE Bivalves are the least “brainy” of the mollusks and, although the central nervous system forms a rather complicated latticework throughout the body, its three pairs of “brains” are merely swellings or ganglia in the larger nerves. The pair of so-called cerebral ganglia control the actions of the lip palps near the mouth, parts of the mantle, and they also receive “nerve notices” from the tiny organs of balance, the otocysts. The second major pair of ganglia are the pedals which supply the foot. This pair is large in the clams that use the foot for digging or burrowing, but it 1s extremely small or aborted in the oysters in which the foot is not used. The third pair, or vis- ceral ganglia, is usually the largest and supplies the adductor muscles and the visceral mass. The remarkable eyes of the scallops are connected with this pair of visceral ganglia. Many of the bivalve larvae possess true paired eyes, but in all cases these are lost when the animal transforms into the adult stage. The adults of a number of clams and mussels have developed pigment spots sensitive to changing light, but in the scallops true eyes are well-developed. When the shell of a scallop is open there can be seen just within the margin of each valve a line of small, brilliant, emerald-like dots on the mantle, each of which is a small eye fully equipped with cornea, focusing lens, receptive retina and conducting nerves. HOW THEY BURROW AND SWIM There are bivalves that swim, leap, crawl and burrow deeply in mud, sand or clay, and some that bore into wood, rock and even lead casings of submarine cables. Even the rock-bound oyster and the stuck-in-the-mud clam have their days of wandering about as free-swimming larvae before they settle down to a life of permanent attachment or clumsy crawling. The habit of swimming among adult bivalves is rare. The scallops and the Lima File Clams not infrequently swim. Only under the abnormal condi- tion of finding themselves “unearthed” do the Ensis Razor Clams and the Solemya Veiled Clams practice jet propulsion through the water. The Razor Clam swims backward in quick, short jerks by first extending its long cylin- drical foot out from the shell and then suddenly withdrawing it with great force. This action, together with the closing of the shell valves, quickly forces the water within the mantle cavity out through the openings at the anterior or foot end. Thus the razor clam darts through the water with its pumping foot to the rear. In Solemya, the foot is in front of the animal as it swims. In this case the water is admitted around the foot but is ex- pelled from the opposite end through the siphons. opel American Seashells The highly developed swimming ability of the scallops accounts for the migratory powers of the great schools of these active bivalves. One would normally expect the direction of swimming taken by a scallop snap- ping its valves together to be “backward” in the direction of the hinges. Although that type of movement is on rare occasions used as an escape measure, the typical swimming movement is in the opposite direction with the free edge of the shell going in front, so that the animal appears to be taking a series of bites out of the water. This odd action is made possible by the vertical, curtain-like edges of the muscular mantle. When the valves are snapped shut by the powerful adductor muscle, water is driven out, not past the mantle curtains but through the regions around the hinge or ears of the shell. By manipulating these curtains, which can be extended or with- drawn locally, the scallop is able to vary the amount and position of exodus of water and hence can direct its course. If accidentally turned over onto the wrong valve, the scallop can execute a neat flip and regain its normal position. While the scallop always swims with its valves in a horizontal plane, the Lima File Clams most frequently progress edgewise, that is, with the breadth of the valves vertical or slightly oblique. The long, colorful tenta- cles of the Lima keep the animal momentarily suspended in water while the valves are being opened in preparation for another “bite” forward. The Lima 1s a poor swimmer and, because of its habit of building nests under rocks, apparently has no incentive to undertake migrations as is done by <_< = FOOT SHELL ra ain ‘ ‘ t a b ‘eS d Figure 17. The mode of locomotion in the bivalve, Yoldia limatula. a, the foot is thrust forward; b, the muscular flaps are spread apart to form an anchor; ec, the foot is withdrawn, thus pulling the animal forward; d, by closing the flaps together, the foot is made ready for another thrust forward. (After Drew 1900.) Life of the Clams 45 the scallops. Scallops of the genus Chlamys are equally poor swimmers and, unlike adult Pecten, spin small byssal threads for attachment to the bottom. Burrowing in sand and mud is accomplished by the foot of the bivalve. The principle is the same in all digging clams. The foot is slowly protruded with the pointed tip wriggling down into the mud. During this extension the end of the foot is kept small, but when it reaches its greatest extension the end is suddenly swelled into a great bulb and the whole foot becomes very rigid. This is accomplished by injecting blood into the foot. The bulbous end serves as an anchor while the clam withdraws the foot and pulls its entire shell deeper into the mud. In the case of the Razor Clam, this action is accompanied by a jet of water against the mud ahead. The dislodged mud is washed up the sides of the shell and out the burrow. The action is similar to the pile driver that opens a way for the pile by a somewhat similar stream of water. Because of its long, powerful foot the Razor Clam is capable of leaping. Generally, when this clam is lying on the surface of the mud, the foot is bent back under the shell and is then suddenly made rigid with the result that it is straightened out with great rapidity. In some cases the animal may turn itself end over end. Many types of clams are especially adapted to boring into hard clay, shale, sandstone and concrete. The Date Mussels, Lithophaga, possess acid- secreting glands as an aid to penetrating limestone. The shell of the clam would of course be dissolved by this acid were it not for the thick, protective covering of periostracum. The Saxicave Borers, Hiatella, may live attached by a byssus on surfaces that they cannot penetrate, or they may bore into soft rock. The boring of the adults is wholly mechanical and is accomplished by rubbing the edges of their shell valves against the rock. Hiatella stays near enough to the surface to allow its siphons to protrude just outside its cone- shaped burrow. In three years the burrow is only three fourths of an inch in length and, after eight years of constant grinding and new gowth of shell, it is only one and a half inches in length. The shipworms burrow long distances into the wood but retain contact with the “outside world” by means of the long fleshy, tube-like extension of the body. Boring is accomplished by the two valves at the anterior end of the tunnel. The denticulated ridges of the shell are the cutting tools, and the foot and muscles aid in rotating the shells back and forth. Burrowing may progress at the rate of as much as four inches a month. In the genus Bankia, at the posterior end of the worm-like animal there are two tiny, feathery pallets. These are used to plug the entrance of the burrow, thus giving protection from enemies, changes in salinity or other adverse condi- tions. When the shipworm is undisturbed, the pallets are drawn inside and the siphons extended into the water for breathing and feeding. CHAR AE Ray, Lives of the Other Mollusks IN ADDITION to the bivalves and snail classes, the mollusks include three other groups which are not so frequently seen at the seashore and whose combined number of living species probably does not exceed two thousand. Two of these classes, the Azmphineura or Chitons and the Scaphopoda or Tusk- shells, are among the lowliest and most sluggish of the mollusks, but the third class, the well-known Cephalopoda, including the squid and octopuses, contains the largest, fastest and most ferocious of all backboneless animals. THE SQUID AND OCTOPUSES—CEPHALOPODA The octopuses and the giant squid have been spine-chilling characters in adventure tales from the days of the ancient Greeks to the undersea film thrillers of Hollywood. Nothing seems more appropriate for a horror scene then the sudden appearance of a tentacle-lashing, beady-eyed octopus just as the hero-diver finds the long-lost treasure chest. And few authors of strange sailing voyages can resist retelling the numerous instances in which gigantic squid have wrapped their arms about the riggings and dragged ship and hapless crew to the bottom. But despite the fanciful nature of most, if not all, of these stories, there are enough scientific facts to convince the skeptic of the ferocity, speed and unusual intelligence of these creatures. Canadian and American fisher- men have long been familiar with giant squid and have often captured 46 Lives of the Other Mollusks 47 crippled individuals and used them for bait. A number of these giants have been brought into museums, and others, stranded on beaches after storms, have been measured and recorded by reliable observers. Architeuthis of the North Atlantic waters is known to reach a total length of 55 feet. The longest arms of this specimen are 35 feet, while the length of the body from tip of tail to the base of the arms is 20 feet. The greatest circumference of the body is 12 feet. Sperm whales which feed upon smaller squid have often been locked in battle with these giants. The skin of these whales is sometimes heavily marked with circular scars caused by the suckers of the squid. The octopus does not reach a very large size. The largest known species occurs on the west coast of North America where, in Alaska, Octopus punctatus attains a length of 16 feet or a radial spread of nearly 28 feet. However, the arms are very small in diameter, and a specimen of such long proportions has a body length of not more than a foot. The octopus oc- casionally found in the Lower Florida Keys is usually less than three feet in radial spread. A dead specimen cast on a beach near Nassau, Bahama Islands, was reported to have an arm length of five feet, and it was estimated that the entire creature weighed about 200 pounds. This, however, is with- out verification. Recent reports of octopus holes 100 feet across seen in the Bahamas from the air were made by untrained observers. There is no satisfactory evidence that any of these species of Octopus has ever inten- tionally attacked man, or that any person has ever been seriously injured by one. The octopus is a rather sluggish and timid creature, seeking shelter in holes and crevices among the rocks, and is usually small. It feeds mainly on bi- valve mollusks but will also eat snails, fish and crustacea. Its hideouts along the shore can usually be detected by the presence of empty shells. Locomotion among the cephalopods varies from a slow, “tentacle-walk- ing” pace, both in and out of water, to the rapid, jet-propulsion darts which are so characteristic of the squid. The so-called aerial “flight” of squid, like that of the flyingfish, is actually a gliding operation and largely depends upon the initial speed attained under water. Squid have frequently landed on the decks of ships a dozen or more feet above the surface of the ocean. When a school of squid is alarmed by an approaching ship or by marauding fish, the fleeing squid dart from the water simultaneously and all in one direction rather than individually fanning out in several directions in the manner of flying fish. The squid darts backward, forward, or in any other direction by means of the reaction of the jet of water which is ejected with great force from the siphon, and direction of movement is controlled by the bending of the siphon. Even when it is confined to a limited space, as in a fishpound, it is not an easy matter to capture it with a dip-net, so rapid is its movement. 48 American Seashells When it is darting rapidly, the lobes of the caudal fin are closely wrapped around the body, and the arms are held tightly together to form a streamlined outline. Except when attacking or escaping, the squid swims less strenuously, using the caudal fin as a balancing organ. There are few sights as interesting as that of squid engaged in capturing and devouring young mackerel. During the summer this chase may be observed from certain wharves in New England. In attacking mackerel the squid darts backward among the fish with the velocity of an arrow, and then turns obliquely to one side and seizes a fish, which is almost instantly killed by a bite in the back of the neck by the squid’s sharp beak. The bite is always made in the same place, cutting out a triangular piece of flesh, and is deep enough to penetrate to the spinal cord. The attacks are not always successful and may be repeated a dozen times before one of the wary fish can be caught. Between attacks a squid may suddenly drop to the bottom and, resting on the sand, change its color to that of the sand so perfectly as to be almost invisible. Ordinarily, when swimming, it is thickly spotted with red and brown but, when darting among the mackerel, it appears trans- lucent and pale. The schools of young mackerel often move close to shore where the water is shallow and offers more protection. In their eagerness to capture fish, the squid frequently force themselves up on the beach where they perish by the hundreds. At such times they often discharge their ink in large quantities. Many species of octopuses and squid possess an ink sac and, in moments of great excitation they may expel a large cloud of black or brown liquid through the siphon. The ink is of a caustic nature and, in addition to its use as a “smoke screen,” it is believed to be distasteful to hungry fish. Two sources of sepia ink are a species of squid found along the southeastern coast of China and another found in the Mediterranean Sea. Many geologic eras ago the cephalopods possessed large and showy shells. Today, however, shells produced by this class are a rarity. The most spec- tacular shell is found produced by the Indo-Pacific Chambered Nautilus, Nautilus pompilius. On our shores, the small, white, spirally coiled shell of Spirula is frequently encountered on southern beaches. The three-inch-long Spirula squid which produces this shell is a denizen of deep water. In other squid the internal shell has been reduced to a simple slab of chalky material (the cuttlefish bone fed to canaries) or, in the case of the Loligo squid, to a thin, elongate shaft of transparent, horny material. By an odd turn of fate, squid are heavily preyed upon by adult cod, mackerel and other fish, and no doubt some young mackerel which have escaped by a tentacle’s breadth have lived to devour later their would-be assassins. Squid are taken in large quantities in nets and weirs each year, and they constitute one of the main fish baits on the Grand Banks. They are Lives of the Other Mollusks 49 frequently eaten by peoples of the Mediterranean area and the Orient but to a much lesser extent by Americans. In contrast to the speedy squid, the octopus is relatively a slow-moving creature, although it can swim away at a fairly rapid rate by using the same water-jet system of propulsion; it lacks the caudal fins of the squid. The underside of the eight arms of the octopus are studded along their entire lengths with cup-like disks or acetabula. When a sucker is pressed against any smooth surface, the center is withdrawn to create a vacuum which en- sures a powerful attachment. An octopus can “tentacle” along with remark- able agility and at night may even take to short excursions out of water. | have known of an octopus kept in a small aquarium in Bermuda to push the lid off the top, crawl down the table and off the veranda in an attempt to reach the ocean. It crawled more than a hundred feet toward the sea before it succumbed and was attacked by ants. There have been many authentic accounts of encounters with octopus on exposed tidal reefs, and a few ob- servers state that the octopus can keep up with a man in a brisk walk. Even more astounding than the locomotive powers of the cephalopods are their amazing displays of bright, glowing lights and color changes. The shallow-water species have embedded in their skin chromatophores whose expansion and contraction are controlled by the nervous system. Emotion, excitation or response to the color of surrounding objects will effect the color changes in the octopus. Among the deep-water squid, many of which are phosphorescent, gorgeous underwater pyrotechnics are frequently dis- played which far outshine the brightest of fireflies and glowworms. Specimens of Lycoteuthis brought up from considerable depths and kept alive in chilled water have had their photographs taken by their own light. The body looks as if it were adorned by a diadem of brilliant gems. The middle organs of the eyes shine with ultramarine blue, the lateral ones with a pearly sheen. Those toward the front of the lower surface of the body give out a ruby-red light, while those behind are snow-white or pearly, with the exception of the middle organ which is sky-blue. Some squid have astonishingly com- plex bull’s-eye lanterns; others have mirrored searchlights. A species of Heter- oteuthis is able to spurt out a luminous secretion from its funnel and the jet of water following it draws out the bright globules into long, shining threads. The sexes in the cephalopods are separate, except for two or three isolated examples. In most of the species females are much more numerous, the ratio of females to males being 100 to 15 in some species of the Loligo squid and 100 to 25 in some of the Octopus. The most outstanding feature is the morphological differences between the two sexes. In the Argonauta or Paper Nautilus, the females are 10 to 15 times as large as the males which completely lack the beautiful shell used by females for storing eggs. The 50 American Seashells female also differs in having its two dorsal arms enlarged at the end to form a veil or mold with which she secretes a shell. In a vast number of species, the males are characterized by having one of the arms modified to form a copulatory organ. This arm is known as the hectocotylus. In certain octo- pods, including the Argonauta, this arm is broken off and left in the female to fertilize the eggs. In all the other groups the hectocotylus is simply held inside the female until copulation is complete. It is interesting to note that more than 2000 years ago Aristotle recorded the presence of the hecto- cotylus arm in the octopus and correctly associated it with its sexual purpose. In the males the sperm is gathered into large sacs or spermatophores of several inches in length. These sacs find their way in some unknown manner into the hectocotylus arm. Each sac contains a tiny, coiled, spring- like filament which spews the ripe sperm out of the sac. The eggs of the cephalopods are laid in various ways. They may be single and floating in the pelagic species, such as Oegopsida, congregated together in a shelly nest as in Argonauta, laid in jelly tubes as in the Loligo squid, or anchored in grape-like bunches under rock ledges as in the Octo- pus. The embryo emerges from the egg fully developed and does not have a free veliger stage. With the aid of a lens it is possible to see the beautiful splotches of bright chromatophores in the skin of the tiny young even before they hatch. About a hundred eggs are laid at one sitting by the octopus; the squid egg strings from one female may contain over 40,000 eggs. Some species of octopuses take pains to watch over their brood of eggs and from time to time may carefully go over them with their tentacles to remove dirt. THE CHITONS—AMPHINEURA Amateurs and professionals alike have found the chitons or coat-of-mail shells an extremely interesting and fruitful field of study, and no collection is complete without at least three or four representatives of this strange group of mollusks. The chitons closely resemble the gastropods except that they bear eight shelly plates. For those who wish to excel in a more serious study of a relatively small class of mollusks, no more inviting series of species awaits the collector than our chitons of the rocky shores. They are dealt with in this book in some detail, for no popular shell book has hitherto at- tempted to open the doors to this supposedly “difficult and poorly known” group. There are nearly fifty species in our Atlantic waters and perhaps twice that number on the Pacific Coast, and yet this represents fewer species than are found in the single family of Wentletraps or Epitonium. Some private collectors, such as the late Dr. R. B. Bales, were able in a few years to make larger and finer collections of Florida chitons than are found even Lives of the Other Mollusks Dl now in our leading museums. Hitherto unknown species await the enthusi- astic specialist in chitons. Except for the more easily recognized and common species, such as the Pacific Coast Katherina tunicata and Amicula stelleri, most identifica- tions require a simple understanding of the various parts of the shells and the patience to remove one or two of the eight valves for observation under a hand lens. Tourist collectors have little time to devote to the special but simple methods of collecting and preserving chitons, and unless they are willing to take to the shore a bucket, penknife, some thin slabs of wood or small glass plates and some soft twine, it would be best for them to concen- trate their searches on the olives and cowries. No one man has done more for the encouragement of chiton collecting in America than Dr. S. Stillman Berry of Redlands, California, and we can- not do better than to follow his simple directions. Curled-up specimens in collections signify ignorance of methods or lack of time while in the field. The chitons are easily flipped from the rock surfaces by quickly in- serting a knife blade beneath the edge of the animal. If the chiton is then quickly transferred to the wet surface of a piece of shingle or glass of the appropriate width, it may be possible to flatten the creature before it curls into a ball. Wood and chiton should be tightly wound with twine or strips of cotton cloth, so that the animal will die in this flattened position. The bound chiton may be soaked in 60 to 80 percent alcohol for an hour or more, or in fresh water, for killing. Unbind, scrape the meat away from the under- side, being careful not to damage the outer rim or girdle. Rewrap on the wood and set.in the hot sun or oven to dry thoroughly. If scientific study is to be done at a later date, it is best to keep a few specimens permanently in a jar of about 70 percent alcohol. When specimens roll up before they can be straightened against your piece of wood, they may be dropped into the bucket of sea water where they will eventually straighten out and allow a second attempt of transfer. Habitats of chitons are usually specialized for each species, some being found only on the underside of rocks between the tide levels, others on wave-dashed headlands, a few in tidepools, others only in deeper waters offshore. Pinna pen shells recently cast ashore often have tiny chitons at- tached on the outside of the shell. Those who do not have dredging facilities may acquire the latter species through exchange or by purchase from several of our excellent shell dealers. A watchful eye and variation in collecting localities will soon bring familiarization with the various habitats of most of the species. 52 American Seashells ’ IDENTIFICATION OF CHITONS It is essential for accurate identifications to refer to one or more of the ten technical terms used in describing the various parts of the chiton. A few minutes’ study of figure 18 will prepare the reader for the photographs, identification drawings and descriptions of the species. Jumping to conclu- sions from the photographs instead of ascertaining the family or genus first will lead to discouraging results. EXTERIOR INTERIOR GIRDLE ANTERIOR VALVE CACCAREONS RADIALLY RIBBED SPINES ! MEDIAN VALVES Beane eeeen SuTURAL TUFT SUTURAL PLATE LATERAL AREA SPICULOSE RADIADIALLY NODULOSE FRINGE MEDIAN VALVE se ee DIVARICATING LINES TuGum PLEVRAL TRACT SCALES CENTRAL AREA GRANULES aN MucRo POSTERIOR VALVE Figure 18. Parts of the chiton shell. All the chitons discussed in this book bear eight shelly valves which cover the body of the creature and are bound together by a leathery girdle. The chitons without valves (Aplacophora) are too rare to be conveniently included here. A view of the underside of a living chiton will show the rather small, separate head and its mouth and, behind this, the larger, ob- long foot. On each side of the foot is a straight row of closely packed gills. The head bears no tentacles or eyes, although the valves of many chitons bear numerous shell eyes. Each chiton possesses three types of valves: (1) the anterior valve at the head end, (2) six intermediate valves, and (3) the posterior valve at the hind end. The shape and ornamentation of these valves are used for identification purposes, and for this reason the various areas of the valves have been named. Removal of the last two valves by the soaking of dried Lives of the Other Mollusks 53 specimens in warm water for five or ten minutes will usually afford sufficient information. The upper surface as well as the under surface of each valve has characteristic areas which aid in identification. In one family of chitons, the Chitonidae, the upper surfaces of the valves of some species bear microscopic eyes which consist of an eye capsule, cornea, iris, lens, retina and optic nerve, but they are probably useful only in sensing changes of light intensity and passing shadows. The girdle is the leathery rim which encircles the eight valves. In some species the girdle entirely or partially covers the valves. The surface of the girdle may be covered with beautiful little scales or with spines, hairs or tufts of bristles. Unfortunately these characters vary among individuals and cannot always be used to separate species, although the general types are fairly reliable in distinguishing genera. The radula or ribbon of teeth is very long, and is composed of thick and dark amber-colored teeth. There are usually about seventeen teeth in each transverse row, in the following order reckoned from the center: one simple, small central; flanked on each side first by a translucent minor lateral and then by a major lateral which bears a conspicuous black cusp; next, two boss-like uncinal plates; then a twisted spatulate uncinal; and, finally, three scale-like external uncini. The radula of the chitons have not been demon- strated as useful characters in separating species because of their great vari- ability, although some workers claim that the major laterals are useful. The sexes are separate in the chitons. Some species lay eggs in a glu- tinous, indistinct mass. There may be a free-swimming veliger stage in some species. In other species the young live under the mantle edge of the mother for protection. THE TUSK-SHELLS—SCAPHOPODA To our Northwest Pacific Indians and our early pioneers the tusk-shells were a familiar form of wampum, but today few Americans would recog- nize one on sight. The 200-odd known living species are for the most part inhabitants of deep water, although a few of our American species live in rela- tively shallow water and are frequently washed ashore. The shells resemble miniature elephant tusks open at both ends, and the sluggish creature lives embedded obliquely in sand and mud, with only the small end of the shell projecting above the surface of the substrate. Like many gastropods, the scaphopods possess a single shell and a set of radular teeth but, like the bivalves, they have a nonlobed velum in the larval or veliger stage, and in adulthood have a wedge-shaped foot and lack a definite head. They lack gills but absorb oxygen from the sea water through the tissues of the mantle. Water is first taken in through the small 54 American Seashells posterior end of the tube-like shell. “he water slowly builds up inside the mantle cavity of the animal over a period of about ten minutes; then, after a short period of rest, the water 1s suddenly expelled in the opposite direction. As in the manner of feeding among the bivalves, ciliated ridges within the mantle ensure passage of food particles to the region of the mouth. How- ever, the primary method of feeding is by means of a number of long, ce- phalic filaments or captacula which are anchored to the two flattened lobes flanking the mouth. The club-shaped ends of these tiny filaments are tactile and prehensile and are capable of capturing Foraminifera and other similar minute organisms. These captacula project out in all directions from the ecranetenytereee SOONG a POSTERIOR ORIFICE MANTLE CAVITY Figure 19. a, Diagrammatic drawing of the internal anatomy of Dentalium; b, radular teeth of Dentalium; c, the central tooth found in the radula of the Siphonodentalidae. larger, anterior end of the shell. Frequently, they are broken or torn off in the searchings through the sand but are soon regenerated. This accounts for the difference in length of the captacula in many specimens. The embryonic shell or prodissoconch of the scaphopods is cup-shaped and consists of two shelly valves, which subsequently unite to form a tube. They may still be seen at the initial end in some specimens of Siphonoden- talium, but are always absent in adult Dentalium. The adult shell is open at both ends. It is added to at the larger, anterior end by the mantle edge, while at the posterior end there may be a gradual loss of shell through wear and absorption. The tiny posterior slits or notches that are characteristic of some species are formed by reabsorption of the previously solid shell wall. The shell wall is made up of three thin layers of calcareous material; this is In contrast to the similar-appearing worm-tubes that have only two layers. In cross-section, the shell may be round, slightly elliptical, octagonal or polygonal in shape, depending upon the species. The presence or absence of Lives of the Other Mollusks 55 microscopic longitudinal or concentric riblets and the nature of the apical slits are often useful for identification. Few of our American species, other than a few pinkish or yellowish forms, can boast of colorful shells; but in the East Indies such forms as Dentalium elephantinum Linné are brightly hued in various shades of emerald green and jade. Some species of Dentalium have a terminal pipe projecting out of the posterior end. There are only two families in the class Scaphopoda—the Dentaliidae and the Siphonodentaliidae. Both families are well-represented in our waters, the former by numerous species of Dentalium, the latter by members of the genus Cadulus. Dentaliidae: Shell tusk-shaped, increasing in size regularly with the greatest diameter at the mouth end. Foot conical. Central tooth of radula twice as wide as long. Siphonodentaliidae: Shell bulbous near the middle with the mouth end generally contracted. Foot vermiform, capable of expansion into a rosette-like disk at the end. Central tooth of radula almost square. CELLAR ih V. Collecting American Seashells Instructions for collecting seashells are much akin to revelations of the secrets of good cooking. Everyone has his favorite methods and, despite the most expert advice one may obtain from books, experience is the surest path to success. There are, however, a number of fundamentals which will help guide the collector in obtaining a representative series of our seashells with the least trouble. The hints offered here are more in the order of how collecting problems may be solved than a revelation of how and where to find rare specimens. The most successful collectors mix together four ingredients to obtain what appears to most of us “unusual luck” in finding good shells. These are a knowledge of the habits of mollusks, a familiarization with the physical conditions of the ocean and the seashore, a sensible choice of collecting equip- ment and, perhaps most important, a large proportion of perseverance. The first three of these may be acquired, to some degree at least, from books and from the advice of veteran collectors, but only keen observation in the field and many hours of trial collecting will develop satisfactory techniques. It is true, of course, that strolling the more productive beaches at certain times of year will produce encouraging results, but soon the common species have been collected and more often than not the remaining specimens are far from perfect. The moment a collector ceases to be a beachcomber and begins to search for living mollusks in their natural haunts he has opened unlimited possibilities of acquiring a remarkably beautiful and complete collection. 56 Collecting American Seashells Sul It is most surprising how many treasures within arm’s reach are lost to the uninitiated. A waterlogged board if kicked aside may be found to con- tain three or four kinds of interesting wood-boring clams; a rock unturned at the end of the beach may still shelter a pair of cowries or a nest of orange- tentacled Lima Clams, or the seafan momentarily admired and cast aside may be the holdfast for a colony of rare, purple Simnia snails. All mollusks have their particular ecological niches or favorite haunts, whether a very limited type of locality or more extensive areas such as mud flats, rocky shores or the open ocean. To be forearmed with a knowledge of where our species live will often bring rich rewards from salt marshes, eel-grass flats, mangrove trees, the backs of other marine creatures, the underside of boats or even the stomachs of fish. The tracks made by gastropods on sand or mud bottoms are characteristic for many species and can aid in hunting down live speci- mens. So, too, holes of certain shapes and sizes in the sand flat are a betrayal of the clam occupant deep below. At times it is worthwhile to know when and where gregarious mollusks gather to breed. Their appearance is often clocked not only by the seasons but often by tidal conditions and the time of day. Most intertidal species reveal themselves more frequently about half an hour after the tide has begun to rise. A great number of species are more active a few hours after dark, while others are content to wait until early morning before starting on their foraging missions. Attention to tides, seasonal moods of the ocean and the effects of winds and currents is put to good use by the expert collectors. September seems to be the most favorable time, for instance, to gather shells on the Carolina strands. During late April and early May there is more likelihood of the Purple Sea Snail, Janthina, being w ashed ashore on the east coast of Florida. After winter gales, some New England beaches may be strewn with millions of large Surf Clams, Spiszla. Low tide is obviously the best time to collect, and most collectors make long- range plans to catch the spring tides. Local newspapers publish the times of low and high tides, but many serious collectors prefer to use the Coast and Geodetic Survey Tide Tables to plan well in advance for the lowest tide of the month. Tide Tables for the Pacific and Atlantic coasts may be obtained for a fraction of a dollar from the U.S. Department of Commerce, Washington 25, D.C. As you may well know, the rise and fall of tides are caused by the at- traction of the moon, and to a lesser extent by the sun. Choose the time of the new and full moon for collecting, for that is when the sun and moon are uniting their forces to give the lowest or spring tides. Low tide lasts for about fifteen minutes, but profitable collecting may be done one hour be- fore or after. It is sometimes useful to know that the tides are about fifty minutes later the following day. Be aware of the dangers of rising tides, 58 American Seashells especially if you have waded a long distance out to some small isle at low tide. Tidal currents can sometimes be extremely strong at the narrow mouths of inlets, and swimmers are urged to familiarize themselves with local condi- tions. If one were to take into the field the collecting equipment which has been recommended by friends and books, one would certainly resemble a busy Christmas shopper in full knightly armor. Crowbars, bilge pumps, shovels, rakes, sets of screens, hammer and chisels, even water wings and miner’s caps have been suggested. It is true that these and many other pieces of equipment are ideal for very specific and limited purposes, but for general collecting simplicity and lightness of gear are most essential. If at a later date you wish to collect a certain species which lives in rocks, take along that hammer and chisel. Streamlined collecting in the intertidal areas when it is calm calls for little more than a pair of canvas shoes, bathing suit and a few small cloth bags. Wear shirt and pants if the sun is bright and your tan still under- developed. Two or three cotton bags may be tucked under the belt until ready for use. Most shells may be picked up by hand, and the more fragile ones put in matchboxes or thumb-sized vials. When a breeze is blowing wrinkles on the surface of the water, it is impossible to see the bottom, and many collectors use a glass-bottomed bucket or merely a diving mask floated on the surface to clear a view. A square or oblong bucket about a foot each way and ten or twelve inches high may be made of light wood and the glass set in the bottom and held in place with a thin layer of white lead and strips of molding or quarter-rounds. If the inside is painted dull black reflec- tions on the glass will be held to a minimum. For a clearer view wet the inside of the glass occasionally. The water bucket is useful to those who enjoy diving for shells. It not only serves as a friendly support between dives, but may be used as a collecting receptacle. Diving masks or water goggles are indispensible for collecting many species which are normally found in waters down to twenty feet in depth. A fine-mesh wire screen bought in any kitchen utensil store can be put to excellent use in sandy or muddy areas where many interesting small shells live. Screening for mollusks is a favorite pastime with many collectors, and many types and sizes of screens have been designed. Copper mesh should be used if you plan to screen over a period of a few months. Forceps are sometimes useful in getting small shells out of rock crevices, but in general it does not pay to search individually for minute shells. Mass screening or taking a large bagful of bay bottom or beach drift home for leisurely sorting in the evenings brings richer rewards. Shaking clumps of seaweed over the screen often gives encouraging results, for many uncommon Collecting American Seashells 59 species are found nowhere else. Breaking apart coral blocks often reveals interesting rock-boring clams. DREDGING AND TRAPPING There are few active shell collectors who have not given serious thought to trying their hand at dredging. This is especially true if one has spent sev- eral summers in one locality and acquired a large and representative collec- tion of the littoral and intertidal species. Over half of our American species prefer to live below the low-tide mark and, although storms occasionaliy cast up samples of this rich fauna on our beaches, trapping and dredging are SMALL. HAND DREDGE SAFETY RELEASE OF TWINE OR STRING LONGER VYe-INCH IRON Yone 15° lees WATER GLASS Figure 20. Dredging and collecting gear. 60 American Seashells the only satisfactory methods of collecting deep-water species. In many instances larger and more perfect specimens of normally shallow-water spe- cies are found in moderately deep waters just offshore. Dredging, like fishing, is a science as well as an art. It requires a basic knowledge of boats, equipment and bottom conditions. Firsthand experience is a necessity before satisfactory results can be obtained. It is also an expen- sive operation in which costs increase geometrically the deeper one dredges. Those who are financially willing to spend several hundred dollars in elabo- rate operations are urged to seek the advice of one of several of the Florida or California shell dredgers. However, very profitable collecting in depths less than 100 feet may be undertaken from a rowboat at relatively little expense. One of the prime prerequisites of safe dredging is a healthy respect for the ocean and her many moods. Limit rowing operations to calm inlets and bays. Sudden squalls, high winds, swift currents and blistering sun on the open ocean are serious adversaries to even the “saltiest” fisherman. Prepare for each trip with care, and back your operations with a knowledge of local tides, currents, the weather and bottom conditions. There are many types of dredges, and the larger your boat and engine the more elaborate may be your dredge. For rowboat operations the simplest type consists of a triangular or rectangular iron frame with a pair of iron bridles which are tied together. A fine-meshed fishing net is sewn to the frame. The free end of the net is not sewn but merely tied together, so that the contents can be removed from the back. A net of this sort is apt to be ripped on rough bottom, so that a canvas sleeve or tube open at the back end should be sewn to the frame and allowed to cover the outside of the net. The Burches of California, renowned for their west coast dredging, have had better luck with a triangular dredge and copper screen net. The leading edges of these smaller types, which are rarely more than two feet across, should be sharp and flare a little in order to dig moderately deep into the bottom. Very remarkable results over mud bottoms may be obtained by using a small trawl. This is a modified dredge whose leading edges are of lead- weighted lines. The mouth of the trawl is kept open by a small, slanting board at each end. This type has the advantage of not digging up large quantities of ooze and mud. In waters less than 150 feet in depth, the tow line may be of 1%” or %s’ manila rope, although the tendency for this to float in deeper waters necessitates the use of lead weights placed at intervals along the line. About 300 feet of line will suffice for hauls not deeper than roo feet. Only through trial and error will you learn the many tricks of dredging. The feel of the line will tell you w hether the dredge is cutting into mud or Collecting American Seashells 61 gravel or is skipping over the bottom. Sometimes it is next to impossible to dredge downhill, so try in the opposite direction if your dredge is failing to dig in. On dredges with iron bridles it is suggested that one arm be attached to the frame merely by a small cord, so that it will break loose and free the dredge should it snag on rocks or corals. When hauls are brought aboard they should be screened and washed to remove mud and sand. If this is not convenient, at least the extraneous material may be thrown away and the remainder put in sacks for home sort- ing. In tropical waters, gloves should be worn to prevent serious stinging by certain kinds of sponges. Be sure to make a record of the depth, location and date of haul. Fish and lobster men often bring up rare shells in their traps, and this suggests, of course, the possibility of setting one’s own traps. Successful traps may be purchased or built with a little ingenuity, if the entrances are made so that snails can easily enter. Dead fish or spoiled meat will attract the carnivorous gastropods, but to date no magical “catnip” has been found to lure the herbivorous species. Even simpler than the trap is the system of weighting a burlap bag of spoiled meat with rocks near the low-water line. Nassarius Mud Snails, Melongena Crown Shells and a host of other species may be collected nearby the next night. If you have yet to collect your first live Olive or Terebra shell, wade along the shores of a sandy bay on a quiet, moonlight night, and with the aid of a flashlight follow along the trails in the sand. A doven daytime visits to the same locality will never compare to one hour of night collecting. Not only are sand-dwelling mollusks on the move, but in rocky regions the cow- ries, mitras and murex shells are out from under their hiding places and traveling along in full view. It is perhaps appropriate here to mention the dangers of over-collecting in certain localities. This is to be avoided particularly if certain species have taken several seasons to build up their populations even to a moderate size. By leaving at least most of the immature specimens and perhaps one or two adults, you will assure yourself of good collecting at the same spot at a later date. While it is unreasonable to expect people to roll back the rocks they have overturned, some collectors do this in order to obtain additional speci- mens on the next visit. Once destroyed by sunlight and air, protective algae and sponges need many months to grow back. However, the blame for extinction of many beautiful mollusks at Lake Worth, Florida, and in many other places rests not with greedy collectors but with super-drainage experi- ments, city pollution and construction work. Keeping accurate locality data with specimens you have collected is most essential. Many private collections are eventually left to museums for the enjoyment and use of future generations. Today’s crowded museums 62 American Seashells must rightfully dispose of specimens which have no data and are therefore of no scientific value. Large and beautiful collections representing much time and cost would have been of inestimable value to science had someone only taken the time to record where each specimen was collected. “Aus- tralia,” “Hawaii” or “California” is not enough. An example of good data would be: “North end of Captiva Island, Lee County, Florida. Leo Burry, collector. July 4, 1952.” Many careful collectors add interesting notes con- cerning the depth of water, type of bottom, abundance, and so forth. A rare shell in perfect condition, correctly identified and with accurate data, is almost worth its weight in gold. PREPARING SHELLS FOR THE COLLECTION The beauty and value of a collection depends largely on the manner in which specimens are cleaned and the methods in which the shells are arranged and housed. The majority of snails and clams, whether they be marine, land or fresh-water, may be cleaned of their animal soft parts by merely boiling in fresh or salt water for about five minutes. The meat may be extracted with a bent safety pin or icepick, depending on the size of the specimen. Shells which have a highly glossed or enameled finish, such as the cowries and olives, should never be thrown directly into boiling water. Start them in warm water, bring slowly to a boil, and then let cool gradually. Any rapid change in temperature will crack or check the polished surface. Save the horny operculum or trapdoor of those species that have them. When the shell is dry, a plug of cotton will hold the operculum in the aperture. Many species are difficult to clean even when the boiling system is used. Usually the tip end of the animal’s body remains in the shell of such genera as Terebra, Vasum and Xenophora. Vigorous shaking or syringing with a powerful blast of tap water will get most out. Filling the shell half full of water and setting it out in the shade for a day or so with an occasional syring- ing will help. If odors still persist a few drops of formaldehyde introduced into the shells, plus a cotton stopper, will eliminate the objections. In the Pacific Islands most collectors bury their shells alive a few inches under soft, dry sand. In a few weeks the specimens are dug up and washed. The sand must be sifted for smaller shells and the opercula. Some people who do not object to flies set their shells upside down in the sand and allow blowfly larvae or maggots to clean out the meat in a week or so. Vigorous rinsing of the shell is all that is necessary. Many delicate snails, including most land species and small fragile clams, may be placed in fresh water overnight and then syringed or picked clean. This system works well with Dentalium, Janthina, Marginella, Olivella, Trivia and Cyphoma, although the last four genera may require a two-day soak. Bi- Collecting American Seashells 63 valves are usually the easiest to boil and clean. Allow your pairs to dry in the flat, open or “butterfly” position, as this will permit ready inspection of the hinge teeth for identification purposes. There are many minute species which obviously cannot be boiled and picked clean. Shells less than one third of an inch may be soaked in seventy percent grain alcohol, and then placed in the sun to dry thoroughly. This strength of alcohol is also ideal for pickling squid, octopus or the soft parts of other mollusks. Isopropyl alcohol may be used, but it is best to use this at a fifty percent strength. Never use formaldehyde (or formalin) to pre- serve mollusks. The shell turns soft, loses color and often crumbles away in a few months. When a shell has been cleaned of its soft parts, it must next be prepared for the collection. Most shells are ready for display and most attractive in their natural state. However, a large number of gastropods, whose beauty is hidden by coral and algal growths, are in need of a certain amount of “face lifting.” A stiff brush, soapy water and diligence will usually suffice. Many collectors soak specimens in a strong chlorine solution for a few hours. This removes a great part of the unsightly growths and will not damage the shell. It will also remove the natural periostracum or thin corneous layer on the outside of the shell. However, when you have several specimens to add to your collection, it is best to keep at least one in its natural state. Very few expert collectors use acid in treating shells, since this often gives specimens a very unnatural, although colorful, sheen. It is used occa- sionally to remove limy deposits and to brighten up old specimens. Com- mercial dealers dip the Pink Queen Conch, for example, for five or ten sec- onds in a vat of one part muriatic acid to four parts of water and then rinse in fresh water. Shells may be dipped with forceps in full strength oxalic or muriatic acid for two seconds and then immediately put under running cold water. This may be repeated until the desired effect is obtained, but it should be pointed out that any acid treatment ruins most shells for scientific study. Polishing abalone shells and cutting cross-sections of larger shells require special equipment such as electrically run burring wheels and circular dia- mond cutters. A visit to a shell factory will be of profit to those wishing to undertake this interesting hobby. THE SHELL COLLECTION Although seashells are easy to keep since they do not deteriorate and generally do not fade in color like many insects, they present many special problems in housing because of their many sizes and shapes. There are three general types of collections—the knickknack shelf, the display arrangement and the study collection. 64 American Seashells The first of these is usually the result of a summer’s random beach col- lecting by the novice or a living-room auxiliary to the main collection. Many important private collections have started in this manner. The display collection for museums, libraries, clubs or even the home is limited by the pocketbook and by the type of secondhand display cabinets that can be afforded. Little more is needed than common sense attention to matters of good artificial lighting, attractive but neutral background, neat labeling, choice of specimens and especially the avoidance of overcrowding. The exhibit should be designed for its eye-appeal as well as for its interest. One has a wide choice of themes—a selection of local shells, mollusks of economic or medical interest, shells of odd habits, examples of colors and atterns and a host of others. The labels of exhibits showing classification should bear the scientific and common names and the geographical range. Miniature display boxes with cotton background and glass or cellophane covering are very popular and, if of uniform size, may be neatly stacked in a closet when not in use. CABINET " CARDBOARD TRAY oN ! LABEL BR BALES COLLECTION CIRCLEVILLE, OHIO CATALOG BOOK ZT Fg Pa chen | key | Rk lv a rah wae ee fl inh COLLECTOR DATE | RECEIVED FROM REMARKS FicurE 21. The shell collection. The name “‘study collection” may sound ominous to some but, if a few simple principles are followed, this type of housing will bring more joy and less work than any other system. It is not only neater, more compact and Collecting American Seashells 65 equally as attractive as the display type, but it also permits the collector to locate any specimen quickly and add new material with a minimum of rear- ranging. The simplicity, uniformity and mobility of equipment, such as drawers, trays, labels and vials, and the use of the biological or systematic order of arrangement are the essence of a good collection. The choice of cabinet and style of drawers will be limited, of course, by the collector’s pocketbook. The accompanying designs are the result of many years of observing private and institutional cabinets, and they are offered here as an ideal toward which you can strive. If the cabinet is made in a roughly oblong shape and is about table- height, additional cabinets may some day be set alongside for desk space or set on top of each other without causing the top drawers to be too high to reach. Pine, basswood or any of the whitewoods may be used. It has been reported that certain oaks have a detrimental effect on shells which have been stored away for years. It is best to have a cabinet door which swings open all the way (180 degrees), although so hinged that the drawers may still be pulled out when it is open only go degrees. Some students prefer the type of door which lifts off. The ideal cabinet unit has the following dimensions: outside measure- ments, height 40” (or 80”), width 22”, depth 32”. Runners for drawers, 30” long. If wooden, %4” X 9s” and set 244” apart. If galvanized sheet iron, 214” wide and bent along He midline to form an L. Inside measurements, wooden drawers 20” 30” and 1%”. No runners or handles are necessary on the drawers. All cardboard trays to hold specimens should be 4” in depth, and a‘l their other outside SITIES LIES should be multiples of the STE. type of tray. This unit may be 14” X 2”, the next eee tray 3" X24 then’ 37) < rAd; then 444” X 6”, and the emer of alls o/s Itas advisable to have more than five sizes of trays, since this complicates curating and the making or ordering of future stocks. Odd-sized trays make neat arrangement impos- sible. Cardboard trays covered with glossy-white enameled paper may be purchased in any large city, or a simple style may be made by cutting out and folding pieces of shirtboard as shown in our illustration. The corners are held together by adhesive paper or butcher’s tape. The various sets, or lots as they are called, of each species should be placed in the trays and arranged in the drawer from left to right, beginning at the front. Many students separate the species or genera by turning over an empty box which may bear a label indicating the genus or species. Small glass vials without necks are used to hold smaller specimens. Cot- ton is best for plugging the vials, since corks are expensive, are difficult to obtain for various-sized vials and eventually deteriorate. When a lot consists of a hundred or more small specimens which will not easily go into vials, it 1s 66 American Seashells convenient to use a covered box 3” X 4” and 2” deep. The label should be pasted on the lower left corner of the lid. A duplicate label or a slip of card bearing the catalog number should be placed in the box. Some people can afford to have glass-covered boxes. A catalog is most essential, and its single purpose is to prevent the loss of valuable locality data. If each specimen bears the same number as the label and catalog entry, it can be returned to its proper tray in case of acci- dental spilling. A thick ledger about 12” X 8” may be purchased at a second- hand office equipment store at small expense. Headings may be arranged across both pages as shown in our figure. More space should be given “Local- ity” than any other section. Run your catalog numbers from 1 on up. Do not experiment with mystical letters indicating the locality, collector or date of cataloging, since all this information will be on your label and in your catalog. A card catalog arranged systematically is useless, time-consuming and a duplication of the information already available from your collection. Specimens should be numbered in India ink with a fine pen. Shells that are too small to number may be put in vials or covered boxes, but do not fail to add a small slip bearing the catalog number. The housing of molluscan animals, octopus and other soft-bodied crea- tures which must be preserved in seventy percent grain alcohol is expensive and generally beyond the scope of the average private collector. It may be mentioned, however, that preserving jars with rubber rings and clip-on glass lids are the best. Vials with necks may be plugged tightly with cotton and set upside down in the jars. The mollusk collection should be arranged systematically, that is, in biological sequence, with the first drawer containing the primitive abalones, followed by the limpets and on up to the specialized bubble shells (Bulla). The small chiton, cephalopod and scaphopod classes may be put at the begin- ning of the gastropods or between them and the bivalves. You may wish to place your unsorted or unidentified material in the last few drawers. Once you have a species represented in your collection, do not stop there. Add other lots from other collecting regions. You will then learn to appreciate individual, ecological and geographical variations. Exchanging. An amazing amount of traffic of duplicate material exists throughout the country and in many parts of the world today. Exchanging is an ideal way of sharing your local rich hauls and of obtaining species be- yond your collecting sphere. A list of the many hundreds interested in exchanging is published in several directories of conchologists and naturalists. Sound out your prospective exchanger to learn what species or type of mate- rial he desires, since some advanced collectors are extremely “choosy.” Al- ways give accurate locality data and send as perfect specimens as you can. Some people make up elaborate exchange lists which they send around to es Collecting American Seashells 67 other collectors. Exchanging, although worthwhile, is time-consuming, and great care must be taken that the upkeep of your main collection does not suffer. Excellent specimens with largely reliable locality data may be obtained from a number of dealers. Their prices are often high, but this is justified, at least with regard to locally dredged material, by the high cost of operating boats and replacing dredges. Like antiques and costume jewelry, the prices of shells vary with what people will pay. Shipping. When sending shells on exchange or to some other collector for identification, always include a fully inscribed label with each lot. Most shells are best protected by loose wrapping in old newspaper. Small or fragile shells should be boxed with cotton. Mail or express shipments up to twenty pounds will travel safely in cardboard cartons obtained from the grocery store. The top and bottom should be padded with two inches of crumpled newspaper. Small lots are conveniently sent in mailing tubes. It is inadvisable to send living snails through the mails, and foreign imports of living land and fresh-water mollusks are prohibited by law except by prior permission from The Surgeon General, U.S. Public Health Service or from The US. De- partment of Agriculture, Washington 25, D.C. Identification services. Besides popular books and a few professional papers available in public libraries, there are few places where amateurs may turn for expert determinations. Fortunately, not a few private collectors are even more familiar with their local faunas than are the professional workers. Although some charge small fees for their services, most are only too happy to identify your “sticklers.” It is customary to name only material which has been sorted and which has accurate and detailed locality data, and to send a sufficient series so that the identifier may retain a sample for his efforts. It 1s a breach of etiquette to send material before asking if the identifier is willing to undertake the task. Sending photographs is highly unreliable and is tanta- mount to saying you do not trust the specimens out of your hands. Some museums will identify specimens if you are unable to do so after serious effort, and this, of course, can be done only if the curator or research worker has the time. Never send more than five species at a time. It is surprising how many people abuse this service, purely voluntary on the part of the expert, by sending unsorted, data-less shells. It is more important that the profes- sional spend his time in caring for his vast collections, doing his research and writing for the benefit of all, than in identifying for the few. Medical work- ers, agriculturalists, archaeologists, fisheries men, ecologists and other profes- sional malacologists already demand a great deal of his time. 68 American Seashells OUTSTANDING COLLECTIONS There are a number of very lovely private collections in the United States, some devoted wholly to marine species, others limited to land or fresh-water types. Many represent years of collecting, others an expenditure of many thousands of dollars. To mention a few would be to slight many another. ‘The best private collections are in California, Florida, Connecticut, the New York area and Massachusetts. As time passes, private collections are either sold, lost or left to some public or university museum, so that today we find the largest collections housed by public or endowed institutions. The United States National Museum, under the Smithsonian Institution in Washington, D.C., contains what is undoubtedly the largest mollusk col- lection in the world. Until Dr. Paul Bartsch, now retired, was curator, it was second in size to that of the British Museum in London. Today, this study collection contains over 9,000,000 specimens, 600,000 lots or suites and in the neighborhood of 36,000 species and subspecies. Its curator at present is Dr. Harald A. Rehder, and his associates are Dr. J. P. E. Morrison. The Museum of Comparative Zoology at Harvard College, Cambridge, Massachusetts, has risen to second place in the United States within the last fifteen years. It is famous for its well-kept collection of about 7,000,000 specimens, 300,000 lots and approximately 28,000 species and subspecies. Its present curator is Dr. William J. Clench, noted for his development of stu- dents in mollusks. Dr. Ruth D. Turner is assistant curator. The Academy of Natural Sciences of Philadelphia, Pennsylvania, 1s third or fourth in size and contains an unusual amount of valuable material. Its present curator, Dr. Henry A. Pilsbry, has been with the institution for over sixty years, and he has contributed more to our science than any other worker. He was preceded by two equally famous curators, George W. Tryon and Thomas Say, America’s first malacologist. The author is the present incumbent of the Pilsbry Chair of Malacology. In the Midwest, one of our largest fresh-water and land collections is located at the Museum of Zoology, University of Michigan, Ann Arbor. Dr. Henry van der Schalie, an expert on fresh-water clams, is the curator. The Chicago Museum of Natural History in Illinois contains a small but adequate collection and is under the care of Dr. Fritz Haas, a scientist well- versed in many phases of malacology. There are no very large study collections in southeastern United States, although one of the finest exhibit collections is on display at Rollins College in Winter Park, Florida. It is well worth visiting, for the collection is beau- tifully lighted and arranged and is instructively labeled. Of equal brilliance, the Simon de Marco collection of rarities is housed in the commercial Florida Marine Museum near Fort Myers, Florida. Collecting American Seashells 69 Among the leading American collections that in the California Academy of Sciences in Golden Gate Park, San Francisco, stands foremost in western United States. It is a large and well-kept collection, supplemented by an excellent library. Drs. G. Dallas Hanna and Leo Hertlein have in the main been responsible for its successful growth. The Paleontology Collection at Stanford University contains a large series of recent and fossil mollusks. It is particularly strong in material from the Pacific northwest. Its present cura- tor, Dr. Myra Keen, is one of our outstanding malacologists who specializes in marine bivalves. A very large collection of marine mollusks is housed at the San Diego Natural History Society, Balboa Park, San Diego. The Museum of Paleontology, University of California, Berkeley, also has a very large collection. CEA Pi Rew I How to Know American Seashells Tue satisfaction of gradually becoming master of a study and the enjoyment of devoting a full interest to one of the many fields of natural history, whether it be wild flowers, butterflies or seashells, are the two strongest motivations among naturalists in their search for new facts and additional specimens. ‘‘Knowing seashells” is not so much a state of knowledge, attained after so many years of study, as it is a continuous process of adding to our store of information and experience. Through personal observation, by tak- ing advantage of what others have discovered and recorded, and by increas- ing our ability to identify species, we gradually become familiar with our mollusks. What’s the name of that shell? Is it rare or common? How does it live? Where can I find more and better specimens? These are four of the most frequently asked questions among shell collectors. Because people who are incurably or only mildly “shell-shocked” are continually asking for the names of shells, over three fourths of this book is devoted to the problem of recognizing and naming our American seashells. To know the name of a shell is in many ways to know the object itself. What we may gain in observation of the shell, the animal which builds it or the habits of the creature, we can, with its correct name, compare with the findings made by other students. “So this is Sozon’s Cone!” transforms the shell in your collection into an object of rarity and opens the door to fasci- nating accounts of fatal, venomous cone shells or the tales of bygone shell 70 How to Know American Seashells 7A auctions. If Amachis avara is swarming over an oyster bed, no one takes particular note, but the mere mention of the Destructive Oyster Drill, Uro- salpinx cinerea, brings the shell-fishery man to the scene to eliminate the pest. The identification of one of the 6,000 species found in our waters is not always a simple task. True, by flipping through pages of illustrations we may spot the shell in question or at least a near relative. This method will sometimes bring us close enough so that reference to the text will reveal the correct identity. However, unless it is realized that many species differ only in seemingly slight characters and, conversely, that other species show wide variation in color or shape, misidentifications can result. How hopeless a task it would be to separate into species the various color varieties of the Common Coquina Shell (Donax variabilis) or the many shapes and sculptural varieties of the Western Dog Winkle (Thais lamellosa). Yet how many would not at first fail to notice the differences between the shell of McGinty’s Cyphoma and the Flamingo Tongue (Cyphoma gibbosa)? But look at the obvious dif- ferences in the color patterns of the animals shown on plate 8. Marine mollusks are exceedingly responsive to varying ecological con- ditions. The presence of certain salts and minerals in the mud often dictates the degree to which certain colors are developed or to what extent spines are produced. In highly exposed areas, where surf waves pound against the shore, snail shells are usually devoid of delicate sculpture. These differences caused by environment are often difficult to distinguish from those which are genetic or naturally inherent characters of the species. So, too, there is often great genetic variation within a species, just as we have brunettes, blondes and redheads among humans. It is not an easy problem, even for the professional, to define the limits of a species, nor to say with authority that a certain specimen represents a “form” or is an example of a subspecies or even different species. What is a species? Volumes have been written in answer to this ques- tion, and the subject is one of continuous investigation by many biologists working with all forms of animals and plants. Every population of mollusks is inherently different, and these differences, however minute, are morpho- logical, physiological or genetic. One need only collect a common species in several localities along our coast and carefully examine them in order to reach this conclusion. It is this factor of geographical variation, together with timely isolation and selection, which has been largely responsible for the evolutionary production of species. The development of species is a con- tinuous and very gradual process and, when we settle upon a reasonably homogeneous series of populations and label them as, say, Melongena corona, we are merely * snapping a candid camera shot” of a species living today, one whose picture looked quite different several million years ago during the Pliocene period. Within the geographical range of this species we find a 72 American Seashells series of populations on the west coast of Florida which seem to be attempt- ing a “break-away” from the typical form, and to this geographical race the name Melongena corona perspectiva has been given. Perhaps in another million years, through fortuitous isolation (geographical or reproductive) and selection, it will merit recognition as a full species. Elsewhere through- out the range of corona, we find minor groups of variants, some that are individuals stunted by ecological conditions, others that are minor genetic variations which seem to crop up at random in all parts of Florida. These ecotypes, aberrations and varieties, although actors in the evolution game, do not warrant subspecific names. There have been many attempts to define a species. A very excellent summary of the various definitions has been published in Ernst Mayr’s inter- esting book entitled Systematics and the Origin of Species (Columbia Uni- versity Press, 1942). Mayr defines species as groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups by geographical, physiological or ecological barriers. Un- fortunately, this biological concept of species cannot as yet be used exten- sively 1 in the field of mollusks, for malacology 1 iS largely i in the purely descrip- tive and cataloging stages, and the majority of species being described today are still based on the old-fashioned morphological species concept. While the species is considered by some people as an objective entity in nature, nearly everyone agrees that a genus is merely a convenient and arbitrary grouping of closely related species. This is also true of many higher categories such as the subfamily and family which are merely convenient groupings of closely related genera. However artificial, the system is ex- tremely useful, for it permits us to arrange the species in our collections and our scientific reports in a logical, evolutionary and biological sequence. IDENTIFICATION FEATURES These are the many morphological features exhibited in mollusks which are used for identifying species and in understanding the evolutionary rela- tionships existing between members of the higher categories, such as genera, families or orders. It must be realized that in some groups of shells certain types of characters, such as number of spines, shape of aperture or color markings are used to distinguish species, while in other groups these will prove useless and reliance may have to be put on the number of folds in the columella, the number of teeth in the aperture or the sculpturing on the operculum. These key features are pointed out in their appropriate places throughout this book. The verbal tools which are used in the study of mollusks are especially designed to assure a method as accurate as possible for telling apart the How to Know American Seashells 73 GOO Ceteeeee Figure 22. Various shapes of gastropods. a, globose (Lunatia heros Say); b, cap- shaped (Acmaea testudinalis Miller); c, fusiform and with an anal notch on the outer lip (Cerodrillia acestra Dall); d, sinistral or left-handed (Antiplanes vinosa Dall); e, slipper-shaped (Crepidula fornicata Linné); f, high-spired (Terebra nassula Dall); g, low-spired (Architectonica peracuta Dall); h, cone-shaped (Conus); i, whorls freely coiled (Vermicularia spirata Philippi); j, spinose (Murex hystricinus Dall); k, spindle-shaped (Fusinus eucosmuius Dall). 74 American Seashells 100,000 or more living, and many more fossil, species of mollusks. It is im- possible to avoid using technical names for various parts of the shell and its animal, such as apex, spire, whorls, operculum, etc., for most of these words have no counterpart in everyday language. Familiarization with these few terms is gained easily and rapidly as trial identifications and references to the illustrated glossaries are made. Many of the technical terms explained below are not employed in this book, but they are presented for the sake of those readers who intend to use more advanced works. GaAstRoPOD FEATURES Shape of shell. It is this character that is instinctively used at first when identifying a snail shell, and little would be gained in discussing at length what our photographs so clearly demonstrate. However, the shape of the adult shell in some species may differ radically from its young stages as may be seen in the illustrations of the cowries (pl. 6g) or the American Pelican Foot (Aporrhais, pl. 23c). Monstrosities caused by embryological defaults or by injury in early life have always been a source of error in identification, and in certain extreme cases many species have been erroneously described as new. Parts of the shell. As the typical gastropod mollusk grows, it adds to the spiral shell and produces turns or whorls. The first few whorls, or nu- clear whorls, are generally formed in the egg of the mollusk and usually differ in texture, color and sculpturing from the postnuclear whorls which are formed after the animal has hatched. When the nuclear whorls are marked off from the remainder of the whorls they are often referred to as the protoconch. The last and largest whorl which terminates at the aperture of the shell is known as the body whorl. The periphery is an imaginary spiral area on the outside of the whorl, usually halfway between the suture and the base or at a point where the whorl has its greatest width. The Giant Atlantic Pyram (pl. 4q) shows a narrow color band on the periphery of the last whorl. The whorl just before the last whorl often has distinctive char- acters and has been differentiated by the name penultimate whorl. Above this the succeedingly smaller earlier whorls in the pointed apex of the shell are known as apical whorls. The rate of expansion of the growing whorls and the degree to which the succeeding whorls “drop” determine the shape of the shell. The sides of the whorls may be flat, globose, concave, chan- neled or ribbed. The juncture of each whorl against the other forms a suture at the top or above the shoulder of each whorl. The suture may be very fine—a mere tiny, spiral line—or it may be deeply channeled (see Busycon canaliculata, the Channeled Whelk, pl. 23n). Sutures may be wavy, irreg- ular, slightly or deeply indented or impressed. How to Know American Seashells 75 The anterior end of the shell is that end which is in front when the ani- mal is crawling. The aperture, the siphonal canal (when present), the head and the tentacles of the mollusk are at this end. The posterior end is the opposite, where the apex and nuclear whorls are located, hence it is some- times referred to as the apical end. When we speak of the posterior side of a rib or a bar of color we mean the side nearest to the apex or away from the anterior end of the mollusk. The total distance between the two ends of the shell is known as the Jength, although this measurement is often called the height. NUCLEAR WHORLS PARIETAL CALLUS = SPIRE AXIAL RIBS COLUMELLA UMeILICAL SPIRAL. CORDS CALLUS SUTURE LENGTH EIGHT , HELG Pempeer| Booy WHORL PARIE TAL WALL OUTER LIP NUMBER la { y eo fe) BASE 4 . APERTVAE WHORLS ANTERIOR OR S\PHONAL CANAL COLUMELLAR PLICAE OR FOLOS Figure 23. Parts of the gastropod shell. The aperture of the shell is the hole or space at the end of the body whorl into which the mollusk can withdraw itself. The edge of the body whorl which borders the aperture is known as the /ip (sometimes called the peristome in technical works). Sometimes the lip is thickened greatly or flar- ing like an old-fashioned blunderbuss. Any startling development of the lip is generally a sign of adulthood. If the lip thickens into an unusually large, rounded, sharp rib it is known as a varix. Varices may be produced at various 76 American Seashells stages in the growth of a shell, and their number and position are used as identifying characters (see Bursa, the frog shells, pl. 9k). For the sake of convenience, the part of the lip which is away from the center of the shell or is not next to the axis of the shell is known as the outer lip. Opposite this on the other side of the aperture is the inner lip or parietal wall which may be thickened, armed with teeth (see Nerita, pl. 4) or have a parietal shield (see the helmet shells, Cassis, pl. 23v). The inner lip is con- tinuous with the thickened axis or columella of the shell about which the whorls are developed. In many kinds of marine gastropods, especially the murexes, the columella extends forward and forms the tube-like anterior siphonal canal. In a few genera there is a small posterior canal formed at the upper or posterior end of the aperture (see Bursa, pl. 9k). The outer lip in a few genera has a very eharieceristic notch or slit. It is longest in the very rare, large Pleurotomaria shell (pl. 3). The “stromboid notch” in the conchs is weak but distinct. In the abalones, Haliotis (pl. 2), the slit is replaced by a series of small, round anal holes. Nearly all the tur- rids are recognized by their “turrid notch” on the upper portion of the outer lip. The Keyhole Limpets, Fisswrella, have reduced the slit to a single small hole which is located at the apex of their cap-shaped shells, although in their young stages the slit is well-developed at the edge of the shell (see fig. 5). The sculpturing on the exterior of the shell—ribs, nodules, cords, threads, indented lines, pits, spines, etc.—are grouped into two basic types: (1) The axial sculpture, that is, any markings, ribs or lines which run across the whorl in line with the axis of the shell or from suture to suture. Some- times it is called longitudinal sculpture. Varices, growth lines and the outer lip are axial features. (2) The spiral sculpture, which is spirally arranged in the direction of the suture or in line with the direction of the growth of the whorls. Thus we often speak of spirally arranged color bands (as in the Tulip Shell, Fasciolaria bunteria, pl. 13c), or axially arranged color streaks (as in the Lightning Whelk, Busycon contrarium, pl. 23-0). The wmbilicus is a hole or chink in the shell next to the base of the columella, which is formed because the whorls are not closely wound against each other at their anterior or basal end. The umbilicus may be quite large and deep as in the sundial shells, Architectonica (pl. 4m). Commonly there is a spiral cord in the umbilicus which may terminate in a button-like callus. Some species are differentiated by the size, position or color of this umbilical callus (see Polinices duplicatus, pl. 5k). About a fourth of our marine spe- cies are umbilicated to some degree or another. Teeth (not to be confused with the radular teeth in the animal’s pro- boscis or mouth cavity) are often present in the aperture. The Distorted Shell, Distorsio (pl. 252), is an extreme example, but some shells have teeth on the parietal wall only (Nerita) or on the inside of the outer lip (Cassis). How to Know American Seashells Vy The periostracum is a horny covering which overlays the exterior of the shell in many species and, like the shell, is secreted and shaped by the fleshy mantle of the animal. The periostracum (erroneously called the epi- dermis) may be very thin and transparent or only slightly tinted (as in some volutes, moon shells and the smaller conchs); or it may be like a thick coat- ing of shellac which flakes off when dry (as in the Queen Conch, Strombus gigas). In a few buccinids, some frog shells (Lampusia) and the vase shells (Vasum), the periostracum may be very thick and often have clumps which simulate hairs and bristles. It is wholly absent in many groups, including the cowries, olives and marginellas. It is primarily a protective coating and pre- vents damage from boring sponges and water acids. When axial and spiral sculpturing are equally prominent and cross each other at right angles, a cancellate or decussate sculpture is produced. Reticu- late sculpture is similar, but the lines do not cross at right angles. Growth lines are mentioned in many of our descriptions and these refer to the axial lines which run parallel to the edge of the apertural lip. These are irregularities in the shell, usually very small but sometimes coarse, which mark places where growth of the shell was stopped for a relatively long time. Sometimes the lip of the aperture becomes stained or slightly thickened dur- ing these brief rest periods (probably a few days apart), and, when addi- tional growth takes place, these blemishes are left as growth lines. Figure 24. Various types of opercula. a, calcareous (Turbo); b, under surtace of same showing the paucispiral, corneous layer to which the foot muscle is attached, c, calcareous and paucispiral (Nerita); d, paucispiral and corneous (Littorina); e, ungulate and corneous (Busycon and Vasum); f, multispiral and corneous (Livona); g, concentric and corneous (Buccinum). The operculum is a horny or calcareous plate firmly attached to the dorsal side of the posterior end of the foot. When the head and foot are withdrawn into the shell, this “trapdoor” is the last part to be pulled in, and it thus serves as a protection against enemies and, in many species, seals the shell from either noxious fluids or the drying effects of the sun and air. When the foot is extended and used in crawling, the operculum serves as a foot-pad on which the heavy shell may rest and rub without injury to the soft foot. The operculum is present in many families of marine mollusks, and it often 78 American Seashells serves as a useful identification character. It is absent in adults in the follow- ing families: Marginellidae, Cypraeidae, Tonnidae, Haliotidae, Acmaeidae, Fissurellidae, Janthinidae, and nearly all of the sea slugs (opisthobranchiates, nudibranchs, bullas, etc.). Some genera lack this organ, such as Oliva and Cy praecassis, although their close relatives, Olivella, Ancilla, Phalium and Cassis possess well-developed opercula. Nearly all Voluta are without the operculum, except our West Indian Music Volute. This is also true of the genera Conus and Mitra whose various species may or may not possess one. In the Alaskan volute, Volutharpa ampullacea Dall, 15 percent have an oper- culum, 10 percent only traces of the operculigenous area and 75 percent without a trace of either. The presence or absence of this part of the animal is not always a good classificational character. Many families, genera and species (although not in so many cases as generally believed) possess a characteristic type of operculum. Caleareous or hard, shelly opercula are found in the turban shells (“‘cat’s eyes” of Turbo), the rissoids, the nerites, and the natica moon shells. The color and sculpturing of these opercula are used for identification purposes. The liotias (Liotidae) possess a horny operculum which is overlaid by rows of calca- reous beads. Among the horny or corneous opercula there are several im- portant and characteristic types which we have illustrated in figure 24. The radula. ‘The minute teeth or radula (also called the odontophore or lingual ribbon) located in the mouths of all classes of mollusks, except the clams, are so very distinctive in the various families, genera and species that they have been used as a fairly reliable identification criterion. Our present arrangement of the gastropod families is based largely upon the radula, al- though many other anatomical characters of the animal and shell are equally important. The Greek naturalist, Aristotle, mentioned the radula of snails as early as 350 B.C., but a fuller account was given by the Dutch naturalist, Swammerdam, in the seventeenth century. The Italian malacologist, Poll, was the first to figure the radulae of gastropods, cephalopods and chitons. The radula is attached to the floor of the buccal cavity or inner mouth and consists of a ribbon-shaped membrane to which are attached many small, fairly hard teeth. The radula ribbon is maneuvered back and forth in some- what licking fashion as the animal rasps its food. The teeth are arranged in transverse rows on the ribbon (see fig. 6). The number of rows may vary from a dozen (in some nudibranchs) to several hundred. Each transverse row contains a specific number of teeth, depending on the family or group to which the snail belongs. In the taenioglossate snails (many families, includ- ing Cy praeidae, Strombidae, Cerithiidae and Littorinidae) there are generally only seven teeth in each row, but each of these teeth has a distinctive shape and a specific number of tiny cusps on its edges. The tooth in the center is called the rachidian or central. Flanking this tooth on each side is a Jateral. How to Know American Seashells 79 Beyond each lateral there is first an inner marginal and finally an outer mar- ginal. This makes seven teeth in all. In the rachiglossate snails (Muricidae, Buccinidae, Olividae, etc.) there are only three teeth per row—the rachidian and a strongly cusped lateral on each side. The four toxoglossate families (Conidae, Turridae, Terebridae and Cancellariidae) have lost their rachidians and laterals and have retained only the marginals. The docoglossate snails (Acmaeidae and Patellidae) have less than twelve teeth per row but are peculiar in that there are two to four identical rachidians or centrals. In the rhipidoglossate families (Trochidae, Fissurel- lidae, Neritidae) the radula is very complicated, and the very numerous lat- erals at the end of each row are called wncini. Among the gastropods which do not have a radula are the Pyramidellidae, Eulimidae, the genus Corallio- phila, adult Harpa and a few genera of nudibranchs. ef \ e ADA a= Figure 25. Types of radular teeth found in the prosobranch gastropods. a, rhipidoglossate (Calliostoma doliarium Holten); b, taenioglossate (Littorina irro- rata Say); c, rachiglossate (Purpura patula Linné); d, toxoglossate (Conus clarki Rehder and Abbott); e, reduced rachiglossate (Scaphella junonia Shaw). All greatly magnified and representing only a single transverse row of teeth. We have figured several main types of gastropod radulae (fig. 25), but other examples have been included in the systematic section when they are of especial use in identification. It is not expected that many amateurs will want to prepare and examine radulae but, because so many serious private collectors and many biology students will find this identification tool indis- pensable, we have inchuded brief instructions on the preparation of radula slides. Preparation of the radula. In large specimens, such as the whelks or conchs, the proboscis may be slit open from above and the round buccal mass removed. Occasionally, the proboscis is withdrawn far inside the ani- mal, but it is easily located below the thin skin on the dorsum just posterior to the tentacles. The flesh may be torn away with the aid of small dissecting needles until the glistening, worm-like radula pops out. In order to remove 8() American Seashells FicurE 26. Various shapes of bivalves. a, spinose (Echinochama californica Dall); b, quadrate (Arcopsis adamsi E. A. Smith); c, orbicular or circular (Divaricella) ; d, rostrate (Nuculana hamata Cpr.); e, trigonal (Crassinella), f, fan-shaped or pectinate (Aequipecten irradians amplicostata Dall); g and h, obliquely ovate and aequivalve (Crenella columbiana Dall); i, elongate (Ensis directus Conrad), j, mussel-shaped (Modiolus modiolus Linné) ; k, ovate (Spiswla polynyma Stimpson). How to Know American Seashells 81 the last traces of flesh, the radula may be soaked in a saturated solution of potassium hydroxide (KOH) for a few minutes. A solution of common lye will do as well. Animals whose flesh has been hardened by a preservative will have to be carefully boiled for a few minutes or soaked overnight in KOH or lye. Small specimens may be dropped whole into this alkaline solution if only the radula is desired. Transfer the radula successively to several watch-glasses of clean water in order to rid it of all traces of KOH. The radula may then be placed in one or two drops of water on a clean, glass microscope slide and, by observation under the dissecting microscope, a few teeth may be teased apart with fine needles. Leave some of the ribbon intact to show the relative position of the teeth. Add a square cover slip for study under the compound microscope. In water mounts such as these, stains are usually unnecessary. This temporary preparation may be permitted to dry for a day, the cover slip gently lifted, a few drops of euporol or mounting medium added, and the cover slip replaced to make a permanent slide. Some workers prefer to go from water to eosin stain to ninety-six percent alcohol and then to euporol, but this is an unnecessary elaboration. There are also excellent, permanent, plastic mounting mediums on the market. Canada bal- sam and glycerine jelly eventually deteriorate. Keep in mind that KOH or lye will burn flesh and eat holes in clothing. PELECYPopD FEATURES Shape of shell. In most families of bivalves, the shape of the shell is extremely important as a species character, and only in a few groups, such as the oysters and mussels, is shape so variable within a species as to be of little taxonomic value. Shape of shell, as a whole, is of little value in deter- mining families or genera, except in a few instances such as Pecten, Spon- dylus and Pinna. Parts of the shell. The two valves of a clam are bound together by a brown, chitinous Jigament, and usually hooked together by a hinge which 1s furnished with interlocking teeth. The valves are kept closed by powerful, internal adductor muscles bu kept spread open by the action of the liga- ment when the animal relaxes or after it is dead. Each valve is a shallow, hollow cone, with the apex, from which point growth of the valves com- mences, turned to one side. This apex is termed the wmbo (plural: umbos, umbones) or beak. The hinge and its teeth are usually just below the beak on the inside of the valve. The prodissoconch is the embryonic shell of the bivalve, and corresponds to the protoconch or nucleus of the gastropods. It is generally eroded away in adults, but when preserved it serves as a useful identification character, especially in such groups as the oysters. Right and left valves. It is important to distinguish one valve from the 82 American Seashells other and to determine which is the anterior or posterior end, for many identification features are used in relation to these orientations. The dorsal or upper margin is located on the beak or hinge side; the ventral margin is the opposite side. The beaks usually are pointed or curved toward the ante- rior end which is generally the less pointed end of the shell. The ligament in the great majority of cases is posterior to the beaks. When present, the heart-shaped impression called the /unule is anterior to the beaks. When a clam is placed on its ventral margins on the table with the dorsal hinge mar- gin up, and with the anterior end away from the observer, the right valve is on the right, the left valve to the left. Another quick way is to observe the concave, interior of a valve with the hinge margin away from the observer and to locate the U-shaped pallial sinus impression (see below). If the sinus opens toward the left, it is a left valve, and vice versa for the right valve. ANTERIOR LIGAMENT POSTERIOR LATERAL ANTERIOR TooTH LATERAL TooTH CARDINAL TEETH LUNULE a yoo PALLIAL Seo en Muscre SCARS RRA Ce DISK a LIGAMENT ESCVUTCHEON <— — eIenT——_ ——- —— > PALLIAL LINE VENTRAL MARGIN Figure 27. Parts of the bivalve shell. In most bivalves, the two valves are of the same size (equivalve), but in some genera one valve is larger and slightly overlaps the other (imequivalve). In Ostrea, Pandora and Lyonsia, the left valve is the larger; in Corbula, the right valve is the larger. A bivalve is said to be equilateral when the beak is midway between the anterior and posterior ends of the valve. Most bivalves, however, are imequilateral with the beak placed nearer one end. In many forms, the margins of the valves do not fit closely together, but have an opening called the gape somewhere along the margin. In the Soft- shelled Clam, Mya, the gape is posterior and through it protrudes the siphon (siphonal gape); in Rocellaria it is anterior and large and serves for the How to Know American Seashells 83 passage of the foot. Some clams, such as Solem and Ensis, gape at both ends. In Arca there is a small notch or opening on the ventral margin for the passage of the anchoring organ, the byssus. This is called the byssal notch. The ligament is a brown, horny band located above the hinge, and is generally posterior to the beaks. As a rule, the greater part of the ligament is externally placed on the shell, but in some genera it may be partially or entirely internal. The ligament consists of two distinct parts, which may occur together in the same species or separately in others—the ligament proper and the internal cartilage or resilium. In most cases, the two portions are intimately connected with one another, but in some clams, such as Mya and Mactra, the cartilage is entirely separate (the resilium) and is lodged within the hinge in a spoon-shaped chondrophore. The external ligament is inelastic and insoluble in strong alkali (KOH). The cartilage is very elastic, slightly iridescent and soluble in KOH. Muscle scars or impressions. ‘The interior, concave surface of the valve Figure 28. Various types of bivalve hinges. a, Arcidae (Noetia ponderosa Say), b, Spondylidae (Spondylus); ce, Cardiidae (Dinocardium vanhyningi Clench and Smith); d, Veneridae (Tivela stultorum Mawe); e, Veneridae (Callocardia texas- ana Dall); £, Lucinidae (Phacoides annulatus Reeve); g, Mactridae (Mactra alata Spengler); h, Tellinidae (Tellina idae Dall); i, Carditidae (Venericardia); j, Mac- tridae (Rangia); k, Crassatellidae (Crassinella lunulata Conrad); 1, Periplomatidae (Periploma discus Stearns); m, Corbulidae (Corbula). 84 American Seashells possesses a number of useful identification features. The large muscles which serve to close the valves leave round impressions on the surface. When two muscles are present, as in the venus, lucine, tellin and other clams, they are known as the anterior and posterior muscle scars respectively. The fine, single-lined impression produced by the muscular edge of the mantle is known as the pallial line. The pallial line may have a U-shaped notch at the posterior end of the valve indicating the presence of a siphon and its siphonal muscles. This is known as the pallial sinus. It is entirely absent in genera possessing no retractile siphons. The hinge. ‘This is one of the most important identification features in the bivalves, and often many hours of fruitless search can be avoided when the major types of hinges and their various parts are understood. There are many types of hinges from those without teeth (edentulous) to those with a complex pattern. We have figured below some of the major types of hinges. The teeth are distinguished as cardinals, or those imme- diately below the umbo, and the Jaterals, or those on either side of the cardi- nals. In many inequilateral bivalves the teeth have become so distorted or set out of place that it is often difficult to distinguish the cardinals from the laterals or to determine which ones are absent. We have labeled the teeth in several groups in the systematic section of this book to overcome this difhculty. In Chama, for instance, the cardinals have been pushed up into the umbo and have become a mere ridge, while the strong anterior lateral has become nearly central and simulates a cardinal. Sculpture. In many groups, such as the scallops (Pectem), sculpture is of paramount importance in determining species. In most other groups it is used in conjunction with other characters. There are two major types of sculpture—concentric and radial—and both of these may be present in many forms, such as ridges, ribs, nodules, spines, foliaceous processes (leaf-like), threads, beads, indented striae (fine lines), etc. Concentric growth lines of varying degree of development are seen on most bivalves. They are always parallel to the margins of the valves, may be exceedingly fine or very coarse, and they generally indicate former growth and resting stages. Radial sculp- ture, running from the umbones to the lower or end margins of the valves, is exemplified in the ribs of Cardium (pl. 32), Pecten (pl. 33) and others. Concentric and radial sculpture may occur together to form a cancellate sculpture as in Chione cancellata (pl. 39h). In a few genera, such as Poro- mya, the valve’s surface may be granulose, as if finely sugar-coated. The periostracum or protective chitinous sheath overlaying the exterior of the valves is present in most bivalves. It may be extremely thin and trans- parent so that it imparts a high gloss to the shell, or it may be thick and matted or even very coarse and stringy so that the valves appear to be bearded, as in Volsella and Arca. How to Know American Seashells 85 NAMES AND NOMENCLATURE In order to discuss the various kinds of mollusks, we must use stand- ardized names which are understood or recognized by students in every part of the world. For this reason, Latin names, or latinized forms, are employed as the official medium for nomenclature. It is not at all necessary to have a knowledge of Latin or Greek in order to label a seashell. Nor is it supposed that one should attempt to remember the names, although it adds to the enjoyment of the study to absorb those of a few commoner species. In fact, it is not difficult to remember such scientific names as Venus, Mitra, Oliva and Conus. It may be of interest to beginners to know that few professional malacologists can remember more than a hundredth part of the total number of names. They, too, consult books to refresh their memories. Popular names. Popular or vernacular names in seashells are in great need of standardization and, while their use sometimes has its drawbacks, there is no reason they cannot become as acceptable to the amateur as have the popular names of birds, fishes and wild flowers. It is true that one species may be known by one name in New England and another in Florida, but these are generally names which are in use by local fishermen and not neces- sarily accepted by amateur shell collectors. In the face of so much name changing in the scientific literature because of legalistic technicalities, the existence of a few provincial popular names seems little enough excuse for not attempting to standardize the common names of seashells. Throughout this book we have presented both scientific and popular names. The latter have been derived from several sources and listed only after careful con- sideration of the evidence. Private collectors, shell dealers, professionals and, in some cases, many popular books, both recent and old, have contributed to the final choice. In a few instances, alternate popular names which are well- entrenched along wide regions of our coast have been listed. Popularization of patronymic names, such as Clark’s cone for Conus clarki, has been simple. Direct translations of the Latin have in many but not all cases been advisable. Many obvious direct translations have been avoided in order to avoid con- fusion with names already used for shells in other regions of the world. It is interesting to note that many popular names in use today were recorded by early eighteenth century writers, and that a few popular generic names are to be found in the writings of Aristotle and Pliny. We have not, of course, employed the rule of using the name first employed as is done in scientific nomenclature (rule of priority). It is hoped that this first listing of 1100 popular names of American seashells will bring fuller enjoyment to the many amateurs who do not desire to “wrestle” with scientific names. Scientific names. A mollusk is given two parts to its scientific name— the genus, which is akin to a surname, such as Smith or Jones, and the species 86 American Seashells which is akin to a first name such as William or Julia. The generic name is always capitalized, e.g., Conus, Strombus or Arca, but the specific name which comes after the genus name is not, e.g., princeps, pilsbryi or floridensis. It is also customary to add the name of the person who described and christened the species; thus the Queen Conch of southern Florida and the West Indies is known as Strombus gigas Linné. If subspecies or geographical races are recognized, the name may appear, for example, as Melongena corona perspectiva Pilsbry or M. corona corona Gmelin, the latter being the typical race. We have employed subgenera throughout the book as center headings. They may also be written into the name in parentheses: Janthina (Violetta) globosa Swainson. It is wrong to put a generic synonym in the middle of the name, as Busycon (Fulgur) carica Gmelin. Some authorities may put the author’s name in parentheses, for example, Modulus modulus (Linné). This means that the species was first described under another genus, in this case, not Modulus but Trochus. Unfortunately, as our science becomes more advanced, parentheses must be used in the ma- jority of the species, and their usefulness becomes offset by the tax on one’s memory as to whether or not they are to be employed in the various species. Modern workers are attempting to abandon this useless frill of nomencla- ture, and in this book they are not used. Dates following the author’s names refer to the date of publication and serve the useful purpose of tracking down the original reference. It should be noted that the “double i” ending is no longer used in species names (not sithii, but smithi). Name changing. ‘here is nothing more annoying than having a well- known and frequently used scientific name changed; and the field of mol- lusks seems to be having its lion’s share of tossing out of old friends for utter strangers. here are two basic kinds of changes—zoological and nomencla- torial. Everyone will condone the former, for it is obvious, as our knowledge increases, that certain genera or even species will be found to be mixtures, and this necessitates separating and applying new names. In this book, for example, Fasciolaria gigantea is changed to Pleuroploca gigantea. The Horse Conch, P. gigantea, does not have characters like those of the tulip shells, and it cannot be put in the genus Fasciolaria with such species as F. tulipa Linneé and F. hunteria Perry. For the same reason, what has been called by many workers Ostrea virginica is now Crassostrea virginica. Venus merce- naria is now Mercenaria mercenaria. Nomenclatorial name changing is hardest for everyone to accept. As not infrequently happens, a species may be given several different names inadvertently by various authors. The International Commission for Zoolog- ical Nomenclature has set up an extensive set of rules; among these is the rule of priority by which the earliest valid name is chosen if several names are available. Unfortunately, the earliest name may have been overlooked How to Know American Seashells 87 for many years, and its subsequent discovery will “knock out” one which has been in use for a long time. Thus about thirty years ago the whelk genus Fulgur Lamarck 1799 was abandoned for Busycon Roding 1798. The same fate may be met by well-known species. Thus Busycon pyrum Dillwyn 1817 now becomes B. spirata Lamarck 1816. It is believed that “rock bot- tom” will be reached some day, so that few, if any, further changes will occur. Nevertheless, it is with considerable regret that I change a number of familiar names in this book. Occasionally, certain names are conserved or “frozen” by the Com- mission if they are well-established and are in danger of being replaced by an earlier but obscurely known name. The following marine genera of mollusks are on the conserved list: Aplysia, Arca, Argonauta, Buccinum, Bulla, Caly ptraea, Columbella, Dentalium, Mactra, Modiolus, Mya, Mytilus, Neritina, Ostrea, Sepia, Spirula, Teredo. Many others, including very familiar species names, need to be added to this list. There are many tech- nical refinements to nomenclature, and those interested in such matters are referred to Procedure in Taxonomy by Schenk and McMasters (Stanford University Press). Pronunciation of scientific names. There is no official pronunciation established for names, and for certain words it may vary from one county to another. Many pronunciations not based on classical rules have become established and passed on from generation to generation. A few examples, classical or not, are given below: Oliva (all-eeva), Elima (you-lee-mah), Chiton (kite-on), Chama (kam-ah), Chione (kigh-own-ee), Cypraea (sip-ree-ah), Cyphoma (sigh- fo-mah), versicolor (ver-sik-o-lor said quickly), Busycon (boos-eekon), Janthina (yan-theena), Xenophora (zen-off-fora), gigas (rhymes with “jibe gas”: ji-gas), conch (konk), radula (rad-you-lah), operculum (oh-perk- you-lum), smithi (smith-eye), ruthae (rooth-ee). The pronunciations of some of the authors are: Linné (lin-ay) or sometimes Linnaeus (lin-ee-us), Gould (goold), Deshayes (desh-ayz), Orbigny (or-bee-nee), Gmelin (mell- an), Bruguiére (broo-gui-air), Kiener (keen-er), Mighels (my-els), Cou- thouy (koo-thoo-ee). Common abbreviations of names of well-known authors. Although most popular and scientific books spell in full the names of authors of sci- entific designations, a large number of articles and most museum labels bear only abbreviations. For this reason, a short list of frequently seen examples is included: A. Ads.—A. Adams B. and S.—Broderip and Sowerby A. and H.—Alder and Hancock Brod.—Broderip Ag.—Aguayo Brug.—Bruguieére Btsch.—Bartsch Cc, By Ad —c, 8B. Adams 88 American Seashells Cl.—Clench Con.—Conrad Coop.—Cooper Couth.—Couthouy Cpr.—Carpenter Dautz.—Dautzenberg Desh.—Deshayes Dkr.—Dunker d’Orb.—Orbigny (d’Orbigny) Esch.—Eschscholtz Dill.—Dillwyn G. and G.—Grant and Gale Gld.—Gould Gmel.—Gmelin Hemp.—Hemphill Hert.—Hertlein L. or Linn.—Linne; Linnaeus Lam. or Lk.—Lamarck Midff.—Midendorff Migh.—Mighels Mts.—E. von Martens Nutt.—Nuttall Old.—Oldroyd Orb.—Orbigny (d’Orbigny) Pfr.—Pfeiffer Phil.—Philipp1 Pils.—Pilsbry Q. and G.—Quoy and Gaimard Raf.—Rafinesque Rod.—Réding (or Roeding) Rve.—Reeve Sby. or Sow.—Sowerby Val.—Valenciennes Verr.—A. E. Verrill PAR er! Guide to the American Seashells [ Systematic Account | THE SYSTEMATIC ACCOUNT OF THE AMERICAN SEASHELLS includes the scientific and common names, geographical ranges, descriptions, comparative remarks and habitats of 1500 of the 6000 species of marine mol- lusks found in North American waters. The areas covered are from Alaska to southern California and from Labrador to the Gulf of Mexico. Conse- quently a large part of the molluscan fauna of Bermuda, the West Indies, Lower California and the Gulf of California is included. Monographic accounts and more detailed information on the remaining species and their ecology, anatomy and habits may be found by consulting the papers listed by subject matter in the appendix on molluscan literature, & CHARTER Vil Periwinkles Conchs and Other Snails Class GASTROPODA Subclass PROSOBRANCHIA Order ARCHAEOGASTROPODA Superfamily PLEUROTOMARIACEA Family SCISSURELLIDAE Genus Scissurella Orbigny 1823 Subgenus Schizotrochus Monterosato 1884 Scissurella crispata Fleming Crispate Slit-shell Massachusetts to eastern Florida and the West Indies. Europe. 3.5 mm. (% inch) in width and 3.0 mm. in length. 4 to 5 whorls. Fragile, frosty-white in color and sculptured by very delicate reticulations. Umbilicus small, round and very deep. Periphery of whorls angulate and with two thin, sharp spiral lamellae. Between these there is an open slit running from the edge of the thin apertural lip back about ¥5 of a whorl. Uncommon from 60 to 500 fathoms. The Florida Slit-shell, S. proxima Dall (fig. 29), from South Carolina to the Lower Florida Keys, differs in being half as large, with a more rounded periphery, and a higher spire, so that the length is about equal to the width of the shell, and in having a weaker pair of peripheral lamellae. FIGURE 29. Uncommon from 20 to 434 fathoms. Florida Slit- shell, Scissurella Family PLEUROTOMARIIDAE proxima Dall, Genus Perotrochus P. Fischer 1885 Y, , inch (Massa- : ; chusetts to Flor- Perotrochus quoyanus Fischer and Bernardi ida, 20 to 430 Quoy’s Pleurotomaria fathoms). 91 92 American Seashells Gulf of Mexico and the West Indies. 17% to 2 inches in length and width. Umbilicus sealed over. Sculpture of finely beaded, small spiral threads. Characterized by a relatively short but wide slit at the periphery of the body whorl just behind the outer lip. Color dull orange-yellow with darker maculations. Base white. Interior slightly pearly, Dredged from 73 to 130 fathoms. One of our rarest seashells. Subgenus Entemnotrochus P. Fischer 1885 Perotrochus adansonianus Crosse and Fischer Adanson’s Pleurotomaria Plate 3d Cuba and the Lesser Antilles. 3 inches in length, and slightly more in width. Umbilicus round, very deep. Sculpture of coarsely beaded, moderately small spiral threads. Slit on periphery of whorl narrow and very long (% of a whorl). Color cream with a salmon blush and irregular, small patches of red. Base similarly colored. Dredged from 94 to 100 fathoms, but sometimes brought up in fish traps. This is an exceedingly rare species, Family HALIOTIDAE Genus Haliotis Linné 1758 Haliotis cracherodi Leach Black Abalone Plate 2f Coos Bay, Oregon, to Lower California. 6 inches in length, oval, and fairly deep. Outer surface smoothish, ex- cept for coarse growth lines. Usually 5 to 8 holes are open. External color bluish to greenish black. Interior pearly-white. A fairly abundant, edible species although not fished commercially to any great extent. A littoral spe- cies which clings to rocks between tide marks. Some shells may lack the holes (unnecessarily named H. c. holzneri Hemphill, H. c. imperforata Dall and 1. c. lusus Finlay). A subspecies, H. c. californiensis Swainson, occurs on Guadalupe Island and is characterized by 12 to 16 very small holes. H. c. bonita Orcutt is the same as this subspecies. H. c. splendidula Williamson is the typical cracherodi, Haliotis rufescens Swainson Red Abalone Plate 2a Northern California to Lower California. 10 to 12 inches in length, oval, rather flattened. Outer surface rather rough, dull brick-red with a narrow red border around the edge of the shell. Interior iridescent blues and greens, with a large central muscle scar. 3 to 4 HALIOTIDAE 93 holes are open. Fished commercially below 20 feet, especially between Mon- terey and Point Conception. The legal minimum size for sportsmen is 7 inches, and the catch is limited to 5 specimens per person per day. This is a popular food and, when polished on the outside, makes an attractive mantel piece. Haliotis corrugata Gray Pink Abalone Plate 2c Monterey, California, to Lower California. 5 to 7 inches in length, almost round, fairly deep, with a scalloped edge and strong corrugations on the outer surface. 3 to 4 large tubular holes are open. Exterior dull-green to reddish brown. Interior brilliant iridescent. The variety diegoensis Orcutt is the same. Abundant in its southern range. The legal minimum collecting size is 6 inches. Haliotis fulgens Philippi Green Abalone Plate 2b Farallon Islands, California, to the Gulf of California. 7 to 8 inches in length, almost round, moderately deep, and sculptured with 30 or 4o raised, coarse spiral threads. Exterior dull reddish brown, interior iridescent blues and greens. 5 to 6 holes are open. Fished commer- cially in southern California. The legal minimum size is 674 inches. H. splendens Reeve, H. revea Bartsch, and H. turveri Bartsch are the same spe- cies in all likelihood. Haliotis walallensis Stearns Northern Green Abalone Westport, Washington, to Point Conception, California. 4 to 5 inches in length, elongate, flattened, with numerous spiral threads. Exterior dark brick-red, mottled with pale bluish green. 5 to 6 holes are open, and their edges are not elevated. This is a small, relatively scarce species. Haliotis assimilis Dall Threaded Abalone Plate 2d Farallon Islands to San Diego, California. 4 to 5 inches in length, oval, fairly deep, with weak corrugations and weak to strong spiral threads. 4 to 5 holes open, tubular. Outer color mot- tled with brick-red, greenish blue and gray. H. aulaea Bartsch is a little more corrugated than usual, and it may be this species. H. smithsoni Bartsch and HA, sorenseni Bartsch appear to be giant specimens of assimulis Dall. 04 American Seashells Haliotis kamtschatkana Jonas Japanese Abalone Plate 2e Japan, southern Alaska to Point Conception, California. 4 to 6 inches in length, elongate, with a fairly high spire. 4 to 5 holes open which have raised edges. Outside of shell rudely corrugated, but a few specimens may have weak, spiral cords. This is a small species, uncommon in California, but increasingly abundant northward. Haliotis pourtalesi Dall Pourtales’ Abalone Off the Lower Florida Keys. % to 1 inch in length, elongate, with 22 to 27 wavy, spiral cords. Out- side waxy yellow to light-brown with a few irregular patches of reddish orange. A light-orange band runs from each hole to the edge of the shell. Inside pearly-white. A very rare species, and the only one recorded from our eastern coast. It has been dredged from 65 to 200 fathoms. Beware of young specimens from other oceans labeled as this species. Family FISSURELLIDAE (Keyhole Limpets) Subfamily EMARGINULINAE Key to the Genera of Emarginulinae a. Apex at the same level as the base of the shell: ba Withanntermalseptum: 2 4 9) eee Zeidora bb. Without internal septum. pa. ee ee Nes aa. Apex above the base of the shell: c. Slitat anterioredges . 992 Gee 2h) 1) es ee mancimals cc. Slit at anterior middle: d. Funnel around slitoninside. . . . . .. ~~ +«Punceturella dd. No funnel around slit . . . . . . +. +. +. ~~»=Rimula Genus Emarginula Lamarck 1801 Emarginula phrixodes Dall Ruffled Rimula Plate 17-0 Off North Carolina to eastern Florida and the West Indies. % inch in length, thin but strong, and with a small, narrow slit on the anterior slope of the shell near the margin. Base oval. Color translucent- white. Interior glossy. Concentric cords and 20 to 24 radial ribs cross each FISSU RELLIDAE 95 other to form a knobby, cancellate pattern. Dredged occasionally off the Miami area in 35 to go fathoms. Genus Rimula Defrance 1827 Rimula frenulata Dall Bridle Rimula Figure 30d Off North Carolina to eastern Florida and the West Indies. 44 inch in length, thin, very delicate. Anal slit in the middle of the anterior slope of the shell and arrow-shaped. Base elongate-oval. Shell % high as long. Sculpture of fine cancellations. Margin finely crenulate. Color translucent-white to cream or rust, generally a deeper shade at the apex. The commonest species of American Rimula, but rare in collections. Dredged 5 to 150 fathoms, especially off the Miami area. Genus Puncturella R. T. Lowe 1827 Puncturella noachina Linné Linné’s Puncturella Circumpolar; south to Cape Cod; south to the Aleutians. ¥ inch in length, conical, laterally compressed, with an elliptical base. 21 to 26 primary radial ribs between each of which are added a smaller, sec- ondary rib farther down. Margin crenulate. Tiny slit just anterior to the apex, and internally it is bordered by a funnel-shaped cup on each side of which is a minute, triangular pit. Color uniformly white, internally glossy. May be collected under rocks at lowest tides in its northern range but also occurs in waters over a mile deep. Common. Figure 30. Pucturellas. a and b, Puncturella cucullata Gould, %4 inch (Pacific Coast); c, P. galeata Gould, form major Dall; 34 inch (Pacific Coast); d, Rimula frenulata Dall; 4 inch (Florida). 96 American Seashells Puncturella cucullata Gould Hooded Puncturella Figure 30a, b Alaska to La Paz, Mexico. %4 to 1 inch in length, moderately strong. Apex small, elevated and hooked over toward the anterior end. Behind it is a small, elongate slit pene- trating through the shell. Internally the slit is separated from the apex by a calcareous, convex shelf. Exterior with 14 to 23 major ribs and with 1 to 5 smaller radial ribs between the main ones. The fewer the ribs, the stronger they are. Shell dull-gray externally, glossy-white inside. The border is cren- ulated. Found at low tide in Alaska and dredged from 20 to 75 fathoms off southern California. Puncturella galeata Gould Helmet Puncturella Figure 30c Aleutian Islands to Redondo Beach, California. % to % inch in length, similar to cucullata, but with an almost smooth basal edge; with numerous, much finer radial ribs, and with the internal shelf behind the slit reinforced by a second, straight shelf. Commonly dredged in mud from ro to 75 fathoms. Subfamily DIODORINAE Genus Diodora Gray 1821 Keyhole Limpets with the internal callus of the hole truncated and fre- quently minutely excavated behind; shell with its basal margin never raised at the ends. Central tooth of the radula wide. Compare with Fissurella. Diadora is a misspelling. Diodora cayenensis Lamarck Cayenne Keyhole Limpet Plate 17m Virginia to south half of Florida and to Brazil. I to 2 inches in maximum diameter. Orifice just in front of and slightly lower than the apex. Many radial ribs with each fourth one larger. Color variable from whitish, pinkish to dark gray. Interior white or bluish gray. Just behind the callus of the orifice on the inside there is a deep pit. D. listeri is much more coarsely sculptured. A common intertidal to moderately deep water species. It was named by Thomas Say one month after Lamarck’s description as D, alternata. Diodora listeri Orbigny Lister’s Keyhole Limpet Plate 171] South half of Florida and the West Indies. FISSURELLIDAE 97 I to 2 inches in maximum diameter. Similar to D. cayenensis but differs in that: (1) every second radial rib is larger; (2) concentric threads are more distinct and, by crossing the ribs, form little squares; (3) radial ribs often have nodules or scales. Color usually white, cream or gray, sometimes with obscure radial bands. Intertidal. Common in the West Indies. Diodora minuta Lamarck Dwarf Keyhole Limpet Southeast Florida and the West Indies. % inch in maximum diameter, rather thin, depressed. Apex at anterior third of shell. Base elliptical, raised slightly at the center, so that the shell rests on its ends. Short front slope slightly concave, back slope convex. Ori- fice narrow and trilobated. Exterior shiny, with numerous, finely beaded radial ribs. Color white, with many of the ribs entirely or partly blackened. Margin very finely crenulate. Internal callus around hole frequently bounded by a black line. Not very common. Dredged 6 to 72 fathoms, but has been picked up on beaches. Do not confuse with D. dysoni which is more likely to be encountered, especially at Sanibel Island. Diodora dysoni Reeve Dyson’s Keyhole Limpet Plate 17n Florida, the Bahamas and West Indies to Brazil. ¥% to %4 inch in maximum diameter, depressed and with straight sides. Base ovate. Apex slightly in front of the middle and characterized by a blunt knob situated behind the posterior wall of the small, almost triangular orifice. Sculpture of 18 strong ribs with three smaller ones between, and with nu- merous concentric lamellae. Color milky-white or cream with 8 solid, broken or dotted black rays. Margin sharply crenulated with the denticles arranged in groups of four. Distinguished from cayenensis by the shape of the orifice. Moderately common, sometimes washed ashore. Diodora aspera Eschscholtz Rough Keyhole Limpet Plate 18b Cook’s Inlet, Alaska, to Magdalena Bay, Mexico. 1% to 2% inches in maximum diameter, slightly less than 1% as high. The roundish to slightly oval, flat-sided apical hole is 41 the length of the shell and about % back from the narrow, anterior end of the shell. Sculpture of coarse radial and weaker concentric threads. Color externally is grayish white with about 12 to 18 irregularly sized, purplish blue, radial color bands. Commonly found clinging to rocks at low tide. In the south, dredged no deeper than 20 fathoms, and often found on the stems of kelp. 98 American Seashells Diodora murina Arnold Neat-ribbed Keyhole Limpet Crescent City, California, to Magdalena Bay, Mexico. %4 inch in length, similar to aspera, but smaller, with a lower, more rounded apex, with convex sides, a narrower shell, and with finer, much neater cancellate sculpturing. Color white or with few, or many, broken radial rays of gray-black. The apical hole is nearer the anterior end. Mod- erately common on rocks. This is D, densiclathrata of authors, not of Reeve. Genus Lucapina Sowerby 1835 Shell thin, low-conic, with the apex in front of the middle. Orifice rather large, roundish. Margin finely crenulated. Fleshy mantle covers most of the shell; foot larger than shell. Lucapina sowerbu Sowerby Sowerby’s Fleshy Limpet Plate 17h Southeast Florida and the West Indies to Brazil. %4 inch in length, oblong in outline. With about 60 alternating large and small radiating ribs. Also with 9 to 13 raised, concentric threads. Color white to buff, with 7 to 9 small, splotched rays of pale brown. Inside whitish; callus sometimes bounded by an olive-green streak. Outside of orifice not stained. Uncommon under rocks at low tide zone. It has been erroneously called L. adspersa Philippi. Lucapina suffusa Reeve Cancellate Fleshy Limpet Plate 17k South half of Florida and the West Indies. 1 to 1% inches in length, oblong in outline. Much like L. sowerbii, but larger, a delicate mauve to pinkish, and with a bluish-black orifice. Inside grayish to dirty-white. Not uncommon under rocks. Formerly called L. cancellata Sowerby. Genus Lucapinella Pilsbry 1890 Shell depressed, conical, less than %4 inch, with a large orifice and thick- ened margins. Lucapinella limatula Reeve File Fleshy Limpet Plate 171 North Carolina to south half of Florida and the West Indies. ¥s inch in length, resembling L. sowerbii, but smaller with a proportion- FISSURELLIDAE 99 ately larger apical hole which is sharp at its top edge and which is nearer the center of the shell. The ends of the shell are slightly turned up and the sides are slightly concave. Sculpture of about 2 dozen heavily scaled, radial ribs and numerous, fine, thread-like concentric ridges. Color whitish with weak mauve or brown discoloring. Commonly dredged off southeastern Florida, from 6 to 60 fathoms. Lucapinella callomarginata Dall Hard-Edged Fleshy Limpet Plate 18e Bodega Bay, California, to Nicaragua. #4 to 1 inch in length, narrower at the anterior end, quite flat. Base flat and usually with strong crenulations on the under edge. Sides slightly con- cave. Apical hole narrowly elongate, slightly nearer the anterior end, about ¥, the length of the shell and with flat inner sides. Sculpture coarsely cancel- late with the radial ribs stronger and often scaled. Color dark-gray with irregular, darker, radial color-rays. Rather rare under rocks in the low tide zone, Genus Megathura Pilsbry 1890 Megathura crenulata Sowerby Great Keyhole Limpet Plate 18a Monterey, California, to Cedros Island, Mexico. 2% to 4 inches in length, % as high. Apical hole large, with rounded sides, 4% the length of the shell, and bordered externally by a white margin. Interior glossy-white. Basal edge finely crenulate. Exterior finely beaded and light mauve-brown. Animal much larger than the shell, with a massive, yellow foot and a black or brown mantle that nearly covers the entire shell. Common in many low-tide, rocky areas, such as breakwaters, Genus Megatebennus Pilsbry 1890 Megatebennus bimaculatus Dall Two-Spotted Keyhole Limpet Plate 18d Alaska to Tres Marias Islands, Mexico. %4 to % inch in length, low, with ends turned slightly up. Apical hole elongate-oval, located at the center of the shell and about % the length of the shell. Numerous radial and concentric threads give a fine cancellate sculp- turing. Color dark-gray to light-brown with a wide, darker ray on each side of the hole, and occasionally at each end. Interior white to grayish. Animal several times as large as the shell, variable in color—red, yellow or white. Common under stones at low tide. 100 American Seashells Subfamily FISSURELLINAE Genus Fissurella Bruguiere 1789 Subgenus Cremides H. and A. Adams 1854 Fissurella nodosa Born Knobby Keyhole Limpet Plate 17d Lower Florida Keys and the West Indies. 1 to 1% inches in length. 20 to 22 strongly nodulated, radial ribs. Mar- gin sharply crenulated. Interior pure-white. Orifice oblong. An intertidal rock-dweller. Uncommon in Florida and the Bahamas; abundant in the West Indies. Fissurella barbadensis Gmelin Barbados Keyhole Limpet Plate 17f Southeast Florida, Bermuda and the West Indies. 1 to 1% inches in length. With irregular radiating ribs. Orifice almost round. Inside with green and whitish concentric bands. Border of orifice deep-green with a reddish-brown line. Outside grayish white to pinkish buff, generally with purplish lines between the small ribs. Commonly blotched with purple-brown. Lives on wave-dashed rocks. Common. A similar, rather rare species, F. angusta Gmelin, also intertidal and fre- quently covered with calcareous algae, occurs on the Florida Keys. The shell is flattish, pointed in front, and its internal callus is light-brown to red- dish brown, but not bounded by a reddish line as in barbadensis, Fissurella rosea Gmelin Rosy Keyhole Limpet Plate 17e Southeast Florida and the West Indies to Brazil. 1 inch in length, thin, flattish, narrower at the anterior end. Orifice slightly oblong. Many radiating, small, rounded riblets. Color of alternating whitish to pale-straw and pinkish rays. Interior pale-green at the margins, blending to white in the center. Green orifice callus bordered by a pinkish line. Common in beach drift. Do not confuse with the larger, more elevated F. barbadensis. Fissurella volcano Reeve Volcano Limpet Plate 18c Crescent City, California, to Lower California. %4 to 1 inch in length, % to almost % as high. Orifice at the very top, very slightly nearer the somewhat narrower anterior end, and elongate with deep, flat inner sides. Sculpture of numerous rather large, but low and ACMAEIDAE 101 rounded, radial ribs of varying sizes. Base of shell slightly crenulate and with color blotches. Exterior grayish white to dark-slate with numerous radial rays of mauve-pink. Interior glossy-white, often with a fine pink line around the callus at the apex. Foot of animal yellow; mantle with red stripes. Very common on rocky rubble at low tide. The variety crucifera Dall is merely a color form with white radial bands. Subgenus Clypidella Swainson 1840 Fissurella fascicularis Lamarck Wobbly Keyhole Limpet Plate 17g Southeast Florida and the West Indies. %4 to 14% inches in length. Both ends turned up (can be rocked back and forth on a flat table). Orifice toward the anterior end, keyhole in shape. Color a faded magenta. Interior whitish, tinged with pale-green or pink. Inner callus of orifice white with a narrow red line. Uncommon in Florida. Superfamily PATELLACEA Family ACMAEIDAE Subfamily ACMAEINAE Genus Lottia Sowerby 1833 Lottia gigantea Gray Giant Owl Limpet Plate 18) Crescent City, California, to Lower California. 3 to 4 inches in maximum diameter, oval in outline, low, with the apex close to the front end. Exterior dirty-brown, rough, commonly stained with algal green. Interior glossy, with a wide, dark-brown border. Center bluish with an “owl-shaped” whitish to brownish scar in the very center. Very common at or above high tide line where the sea spray may reach them. In the south they grow to a large size. Frequently polished and used as sou- venirs. Genus Acmaea Eschscholtz 1830 Subgenus Acmaea s. str. Acmaea mitra Eschscholtz White-Cap Limpet Plate 18r Alaska to Lower California in cold water. 1 inch in maximum diameter, thick, pure white, conic in shape, and with an almost round base. Apex pointed and near the center. Often covered with small, knobby nullipore growths. Commonly washed ashore. It lives in cold water below the low tide level. 102 American Seashells Subgenus Collisella Dall 1871 Pacific Coast Species Acmaea pelta Eschscholtz Shield Limpet Plate 18n Alaska to Lower California. 1 to 1% inches in maximum diameter, elliptical in outline, with a mod- erately high apex which is placed /% to almost % way back from the anterior end. With about 25 axial, weakly developed, radial ribs. Edge of shell slightly wavy. External color of strong black radial, often intertwining, stripes on a whitish cream background. Interior usually faint bluish white, with or with- out a dark-brown spot. Inner border edged with alternating black and cream bars. A common rock-dweller, Acmaea fenestrata Reeve Fenestrate Limpet Plate 18t Alaska to Lower California. 1 to 1% inches in maximum diameter, almost round in outline, rather high, and smoothish. The northern subspecies, cribraria Gould (pl. 18w), found from Alaska to northern California, has interior with various shades of glossy, chocolate-brown, and with a narrow, solid black border. The exterior is plain dark-gray. The typical southern fenestrata Reeve (pl. 18t), found from Point Conception south, has an external color pattern of regular dot- tings of cream on a gray-green background. Its interior has a small, brown apical spot surrounded by a bluish area and bordered at the margin of the shell with brown. Intergrades occur near Point Conception. This species is the only Pacific Acmaea which lives among loose boulders that are set in sand. It only feeds when submerged. Common. Acmaea conus Test Test’s Limpet Plate 18g Point Conception, California, to Lower California. 34 inch in maximum diameter. Shell low, and like A. scabra, is with distinct but widely spaced, radial ribs. Distinguished from scabra by its glossy, smooth interior which often has an evenly colored brown center. A. scabra has a rough interior center and the brown stain looks smeared. However, this species may be a form of scabra. It is very abundant south of La Jolla and is found with A. scabra and A. digitalis. Acmaea limatula Carpenter File Limpet Plate 18-0 Puget Sound to Lower California. ACMAEIDAE 103 1 to 1% inches in maximum diameter, elliptical to almost round in out- line, low to quite flat. Characterized by radial rows of small beads which sometimes may be crowded together to form tiny, rough riblets. Exterior greenish black. Interior glossy-white, younger specimens having a blue tint. Patch of brown on inside generally weak or absent. Edge of shell usually with solid, black-brown, narrow band. Occasional albinos are cream-brown or tan on the outside. Compare with A. scutum which is smooth and has a barred band of color on its under edge, Acmaea digitalis Eschscholtz Fingered Limpet Plate 18f Aleutian Islands to Socorro Island, Mexico. 1% inch in maximum diameter, elliptical in outline; generally with a moderately high apex which is minutely hooked forward and which is placed % back from the anterior end of the shell. The 15 to 25 moderately devel- oped, coarse, radiating ribs give the edge of the shell a slightly wavy border. Color grayish with tiny, distinct mottlings of white dots and blackish streaks and lines. Inside white with faint bluish tint and with a large, usually even, patch of dark-brown in the center. Edge of shell with a solid or broken, narrow band of black-brown. Common. Do not confuse this species with A. scabra which does not have the “hooked-forward” apex and is not glossy on its internal brown patch. Compare also with persona, Acmaea persona Eschscholtz Mask Limpet Plate 18q Aleutian Islands to Monterey, California. 1 to 1% inches in maximum diameter, with characters much the same as those of digitalis, but differing in being smoothish, larger, often slightly higher, and in having a strong tint of blue or blue-black inside. I am inclined to believe that Pilsbry is correct in considering digitalis as a smaller, ribbed form of persona, despite the fact that recent workers place these two species in different subgenera. It is possible that colder waters allow the smooth persona form to express itself. The Mask Limpet is very common from Monterey north. It is an intertidal dweller where strong waves flush the rock crevices. It feeds mostly during the ebb tide and is more active during dark hours. The small southern subspecies, strigatella Carpenter, is about % inch in size, dark gray-blue inside, and externally with a mass of intertwining or joining radial bars of brown on a bluish or gray-white background. Acmaea scabra Gould Rough Limpet Plate 18! Vancouver, B.C., to Lower California. 104 American Seashells 1/4 inch in maximum diameter, elliptical in outline, generally with a low apex which is placed ¥% back from the front end. The 15 to 25 strong, coarse radiating ribs give the edge of the shell a strong crenulation. Color dirty gray-green. Underside of shell whitish, irregularly stained in the center with blackish brown. Edge of shell between the serrations is stained blackish to purplish brown. A common species found clinging to rocks high above the water line but within reach of the ocean spray. A. spectrum Nuttall is the same species. Do not confuse with the smaller A. conus which is evenly glossed, instead of coarse and dull, on its interior center. Acmaea testudinalis scutum Eschscholtz Pacific Plate Limpet Alaska to Oregon (common) to Lower California (rare). 1 to 2 inches in maximum diameter, almost round in outline, quite flat, with the apex toward the center of the shell. Smoothish, except for very fine radial riblets in young specimens. External color greenish gray with slate-gray radial bands or mottlings. Interior bluish white with faint or darkish brown spot. Inner edge with band of alternating bars of black or brown and bluish white. The name of this species was also known as tessulata Miller. The typical testudinalis from the Arctic Seas and New England rarely, if ever, exceeds a size of 1% inches, is not so round, and has a darker, more con- centrated brown patch on the inside. Intergrades exist in Alaskan waters. The Pacific race was also named patina Esch, Acmaea asmi Middendorft Black Limpet Alaska to Mexico, clinging to the gastropod, Tegula. % inch in maximum diameter, high-conic, elliptical in outline, and solid black inside and out. In the northern part of its range, the Black Limpet is found living attached to the common snail, Tegula funebralis A. Adams. Acmaea triangularis Carpenter Triangular Limpet Southern California to Gulf of California. % inch in maximum diameter, oblong in outline, side view distinctly triangular. Color whitish with 3 or 4 vertical, rather broad, brown stripes on each side. Found among coralline algae from the shore line down to several fathoms. Uncommon. Acmaea depicta Hinds Painted Limpet Santa Barbara, California, to Lower California. ACMAEIDAE 105 % inch in maximum diameter, very narrow, 3 times as long as wide. Sides straight with brown vertiéal stripes on a whitish background. Smooth- ish. This species is found on the broad-leaved eel-grass of the estuaries. Abun- dant in certain localities, such as Mission Bay, Acmaea instabilis Gould Unstable Limpet Plate 18zz Alaska to San Diego, California. 1 to 144 inches in maximum diameter, oblong with a rather high apex. Sides compressed. Lower edge curved so that the shell rocks back and forth if put on a flat surface. Exterior dull, light-brown. Interior whitish with faint brown stain in the center and with a narrow, solid border of brown. Inhabits the stems or holdfasts of large seaweeds, Moderately common. Acmaea insessa Hinds Seaweed Limpet Plate 182 Alaska to Lower California. ¥ to % inch in maximum diameter, narrowly elliptical, with a high apex, and colored a uniform, greasy light-brown. Abundant on the stalks or hold- fasts of the large seaweeds, such as Egregia. Acmaea paleacea Gould Chaffy Limpet Vancouver, B.C., to Lower California. % inch in maximum diameter, very fragile, translucent-brown, 3 or 4 times as long as wide. Sides straight with fine, raised radial threads. Abun- dant on the narrow-leaved eel-grass of the open coast. Atlantic Coast Species Acmaea testudinalis testudinalis Miller Atlantic Plate Limpet Arctic Seas to Long Island Sound, New York. 1 to 1% inches in maximum diameter, oval in outline, moderately high with the apex nearly at the center of the shell. Smoothish except for a few coarse growth lines and numerous, very fine axial threads. Interior bluish white with a dark- to light-brown center and with short, radial brown bars at the edge. Exterior dull cream-gray with irregular axial bars and streaks of brown. A common littoral species in New England. Formerly referred to as A. tessulata Miller. The form alveus Conrad is a thin, elongate, heavily mottled ecological variant which lives on eel-grass, 106 American Seashells Acmaea antillarum Sowerby Antillean Limpet Plate 17a South half of Florida and the West Indies. %4 to 1 inch in maximum diameter, usually very flat, rather thin, oval in outline but narrower at the anterior end. Neatly sculptured with numerous radial threads. Color variable: exterior whitish with a few or many narrow or wide radial rays of brownish green. Interior glossy whitish with a dark- or light-brown callus. Borders or sometimes the entire inside marked by numerous radial lines of purple-brown. These are often divided near the edge of the shell. Uncommon in Florida, but abundant in the West Indies. A. candeana Orbigny and A. tenera C, B, Adams are the same. Acmaea pustulata Helbling Spotted Limpet Southeast Florida, the West Indies and Bermuda. 1 inch in maximum diameter, oval in outline, moderately flat with rounded sides. Shell thick, with coarse axial ribs which are crossed by fine concentric threads. Interior glossy-white, with the central callus yellowish. Exterior chalk-white, dull. Sometimes flecked with red-brown dots and bars. Common. Formerly known as punctulata Gmelin. A deep-water form, which is perhaps a young phase, of this species is very thin, light-rose in color, with a tiny, sharp apex and is occasionally flecked with red. It may be called A. pustulata pulcherrima Guilding, Acmaea leucopleura Gmelin Dwarf Suck-On Limpet Plate 17b Southeast Florida and the West Indies. % to % inch in maximum diameter, high-conic, with numerous, alter- nating black and white rays. The black rays divide into two near the edge of the shell. Radial riblets weak, usually black. Interior white, often stained brown or black on the callus. Frequently found adhering to the underside of large gastropods such as Livona pica. Common. A. cubensis Reeve and A. simplex Pilsbry are probably this species, Acmaea jamaicensis Gmelin Jamaica Limpet Plate 17¢ Southeast Florida and the West Indies. % inch in maximum diameter, moderately high, with roundish sides, thick, with about 15 to 20 rather large, rounded, white radial ribs on a black- brown background. Sometimes completely white. Interior white, occasion- PROCHIDAE 107 ally with a black-spotted edge and with a thickened central callus which 1s light-brown to black. A. albicosta C. B. Adams and A. fungoides Réding are the same. Moderately common in the West Indies, occasionally found on the Lower Florida Keys. Family LEPETIDAE Genus Lepeta Gray 1842 Small, flattish, uncoiled shells which are “hat-shaped,” similar to Acmaea, but the embryonic nucleus is spiral; the animal has no external gills and the proboscis is produced into a labial process on each side. The radula has a median tooth, which in Acmaea is absent. Lepeta caeca Miller Northern Blind Limpet Plate 17] Arctic Seas to Cape Cod, Massachusetts. Y% to % inch in maximum diameter, moderately conic, with straight sides, oval-elongate in outline. Rather fragile, dull-white to brownish exter- nally and with fine, granulose, crowded, radial threads. Interior white or tinged with pink. Apex usually eroded. A common cold-water species often dredged in shallow water off New England. Superfamily TROCHACEA Family TROCHIDAE (Top Shells) Subfamily MARGARITINAE Genus Margarites Gray 1847 Subgenus Margarites s. str. Margarites costalis Gould Northern Rosy Margarite Plate 17t Greenland to Cape Cod, Massachusetts. Bering Strait to Port Etches, Alaska. % to 3% inch in length, a little wider, with 5 evenly and well-rounded whorls. Narrowly and deeply umbilicate. Angle of spire about 90 degrees. Next to last whorl with 10 to 12 smoothish, raised, spiral threads. Columella and outer lip thin, sharp, the latter finely crenulate. Color rosy to grayish cream. White within the smoothish umbilicus. Aperture pearly-rose. Com- monly dredged from ro to 62 fathoms. MM. groenlandicus Moller 1s the same. Formerly known as M. cinereus Couthouy. 108 American Seashells Margarites groenlandicus Gmelin Greenland Margarite Figure 31d Arctic Seas to Massachusetts Bay. ¥ inch in length, *4 inch in width. Angle of spire 110 degrees. Whorls strongly rounded, aperture round, umbilicus wide and deep. Outer lip and columella very thin. Base smooth; top of whorls with about a dozen smooth spiral lirations or almost entirely smooth (form wmbilicalis Broderip and Sowerby). Nucleus glassy smooth. Suture finely impressed. Color glossy- cream to tan. Aperture pearly. Commonly dredged from 5 to 150 fathoms. Figure 31. American Margarites. a, Margarites succinctus Cpr., ¥ inch (Pacific) ; b, Solariella peramabilis Cpr., ¥% inch (Pacific); e, Margarites pupillus Gould, % inch (Pacific); d, Ml. groenlandicus Gmelin, 4% inch (northern Atlantic); e, M. irulatus form parcipictus Cpr., %4 inch (Pacific); f and g, Solariella obscura Couthouy, 4 inch (Atlantic); h, Lischkeia cidaris Cpr., 1 inch (Pacific). Margarites lirulatus Carpenter Lirulate Margarite Figure 31e Santa Barbara, California, to the Coronado Islands. % inch in length, 4 to 5 whorls, strong, semi-glossy. Very variable in color (solid purple, whitish with dark-brown variegations and sometimes with a spiral row of dark squares on the periphery), and variable in the num- ber and strength of the small, smooth, spiral cords. Base rounded. Umbilicus narrow but deep. Suture well-impressed. Interior iridescent. Common in shallow water. M. parcipictus Cpr. and obsoletus Cpr. are forms of this species, EROCHIDAE 109 Margarites succinctus Carpenter Tucked Margarite Figure 31a Alaska to Lower California. 7% inch in length, 4 whorls, slightly wider than long, smoothish except for microscopic, weak threads or incised lines. Umbilicus small, round, deep. Exterior grayish brown, commonly with microscopic, brown, spiral lines. Aperture dark-greenish iridescent. Littoral on algae; common. Subgenus Pupillaria Dall 1909 Margarites pupillus Gould Puppet Margarite Figure 31¢ Bering Sea to San Pedro, California. ¥% to % inch in length, whorls 5 to 6, upper whorls with 5 to 6 smooth- ish, small, spiral threads, between or over which are microscopic, axial, slant- ing threads. Umbilicus a minute chink. Exterior dull, chalky whitish to yellowish gray. Aperture rosy to greenish pearl. Apex usually eroded. A common littoral species in the northern half of its range. Also dredged in 50 fathoms. Genus Lischkeia P. Fischer 1879 Subgenus Turcicula Dall 1881 Lischkeia bairdi Dall Baird’s Spiny Margarite Plate 3c Bering Sea to Coronado Islands, Mexico. 2 inches in length, moderately fragile, sculptured with varying number of spiral rows of fairly large beads. No umbilicus. Shell white with a thin, glossy, yellowish-green periostracum. Interior of aperture pearly-white. This is a choice deep-water species much sought after by collectors. Moderately common in 100 to 600 fathoms. Subgenus Cidarina Dall 1909 Lischkeia cidaris Carpenter Adams’ Spiny Margarite Figure 31h Alaska to Lower California. 1 to 1% inches in length, moderately solid, similar to L. bairdi but with a higher, flat-sided spire. The suture is usually more impressed. Color gray to grayish white. Moderately common from 20 to 350 fathoms. 110 American Seashells Subgenus Calliotropis Seguenza 1903 Lischkeia ottoi Philippi Otto’s Spiny Margarite Nova Scotia to North Carolina. % to % inch in length, equally wide. Moderately thin with a sharp lip. The round, narrow umbilicus is partially covered by the top of the colu- mella. Color pearly-white. Sculpture of whorls in spire with 3 evenly spaced spiral rows of prickly beads. Suture wavy. Base of shell with 4 to 5 spiral threads which bear smaller, often obscure, beads. Nuclear whorls with axial lamellae. S. regalis Verrill and Smith is the same species. Common from 50 to 100 fathoms, Genus Solariella Wood 1842 (Machaeroplax Friele 1877) Solariella obscura Couthouy Obscure Solarelle Figure 31f, g Labrador to off Chesapeake Bay, Virginia. % inch in length, similar to Margarites costalis, bat with whorls made more angular by one large, feebly beaded, spiral cord above the periphery. Base smoothish except for microscopic, spiral scratches. Umbilicus narrower and bordered by an angular rim. Color grayish to pinkish tan, often worn to reveal a pearly-golden color. Aperture pearly-white. Some specimens may have weak axial riblets below the strongest spiral cord on the periphery of the whorl. Commonly dredged from 3 to 400 fathoms, especially on the Grand Banks. Solariella lacunella Dall Channeled Solarelle Figure 32b, c Virginia to Key West, Florida. ¥g inch in length, equally wide, thick, pure white. Whorls convex. Aperture circular, internally pearly. Suture channeled. Whorls with 6 spiral cords, bottom 3 smooth, the upper ones axially beaded. Nuclear whorls glassy, with microscopic axial ribs. Umbilicus round, narrow, deep, lined with spiral rows of coarse beads. Very commonly dredged from 18 to roo fathoms. Solariella lamellosa Verrill and Smith Lamellose Solarelle Plates Massachusetts to Key West, Yucatan and the West Indies. % inch in length, similar to S. Jacunella, but with a much deeper channel ’ at the suture below which are numerous, small axial, short lamellar-like ribs. TROCHIDAE 111 Middle of whorl with a strong, sharp, smooth or beaded, spiral thread. Base of shell smoothish except for one smooth spiral thread near the periphery and one heavily beaded cord bordering the deep, round umbilicus. Entire shell with numerous microscopic incised lines. Very commonly dredged from 35 to 150 fathoms, but also recorded from 683 fathoms. Solariella peramabilis Carpenter Lovely Pacific Solarelle Figure 31b Alaska to San Diego, California. % to % inch in length, equally wide, solid, semi-gloss. Aperture circular. Umbilicus fairly wide, round, very deep. Whorls 7, shouldered just below the suture by a flat shelf. Lower 7% of whorl with numerous weak spiral cords that are smoothish in the last whorl but crossed by numerous axial rib- lets in the early whorls. Color tan with light-mauve stains and mottlings. Interior iridescent. Moderately common from 20 to 339 fathoms. FiguRE 32. a, Gaza watsoni Dall (nat. size); b and ec, Solariella lacunella Dall X4; d and e, Microgaza rotella Dall X4. All from the Atlantic. Genus Microgaza Dall 1881 Microgaza rotella Dall Dall’s Dwarf Gaza Figure 32d, e North Carolina to south Florida and the West Indies. % inch in diameter, spire flat, surface smooth except for a spiral row of low pimples just below the suture. Whorls about 5. Umbilicus fairly wide, very deep, its squarish edge bearing numerous, neat, rounded creases. Colu- mella straight. Color whitish gray with a beautiful opalescent sheen, espe- cially inside the aperture. Top of whorls colored with chestnut, zebra-like axial stripes. Very commonly brought up in dredging hauls off Miami from 50 to 100 fathoms. The form inornata Dall lacks the pimples just below the suture. ti American Seashells Subfamily CALLIOSTOMATINAE Genus Calliostoma Swainson 1840 Calliostoma euglyptum A. Adams Sculptured Top-shell Plate 17w North Carolina to Florida and Texas. %4 inch in length, equally wide. Angle of spire about 70 degrees. Sides of whorls slightly concave. Periphery well-rounded. No umbilicus. Whorls with 6 major, well-beaded, spiral cords between each of which is a much smaller, weakly beaded thread. Color dull-rose, sometimes with axial flam- mules of cream. Nucleus pink or, when worn, dark purple. Moderately common in some localities from low tide mark to 32 fathoms. Calliostoma zonamestum A. Adams Chocolate-lined Top-shell Plate 3n Lower Florida Keys and the West Indies. %4 to 1 inch in length, slightly wider. Angle of spire about 70 degrees. Sides of whorls flat; periphery sharp; base flat. Umbilicus deep, smooth-sided, white. Whorls characterized by ro spiral, beaded threads between each of which there is a dark-chocolate line. Base olive with about 5 to 6 fine, brown, spiral lines. A very beautiful and moderately rare species much sought after by collectors. Calliostoma roseolum Dall Dall’s Rosy Top-shell North Carolina to both sides of Florida and Yucatan. % inch in length, 34 as wide. Angle of spire about 50 degrees. Sides of whorls well-rounded, and with 8 to 9 crowded spiral rows of numerous neat beads. Columella upright, strong, with a slight twist. Color of shell light orange-tan to cream, often with arched splotches of darker color running axially across the whorl. No umbilicus. Aperture pearly-rose. Uncommon from 12 to 100 fathoms, Calliostoma pulchrum C. B. Adams Beautiful Top-shell North Carolina to Florida, the Gulf of Mexico, and the West Indies. ¥g inch in length, 4 as wide. Angle of spire about 50 degrees. Sides of whorls straight. Characterized by a pair of strong, spiral cords just above the suture which are white with distantly spaced red-brown dots. Rest of whorl pearly-green with 6 to 7 very weak (or sometimes strong) beaded spiral threads. Columella almost upright, its inner side rounded, pearly. No umbili- cus. Moderately common from 1 to 4o fathoms, TROCHIDAE ris Calliostoma jujubinum Gmelin Jubjube Top-shell Plate 3p Lower Florida Keys, the Bahamas and the West Indies. % to 1% inches in length. Characterized by the deep, narrow, smooth- sided umbilicus which is bordered by a spiral, beaded thread, and by the swollen, rounded periphery of each whorl, which in the spire is located just above the suture. Color ranges from brownish cream to reddish and is often maculated with white splotches near the periphery. Typical jujubimum has a spire angle of about 50 degrees; the spiral threads on the whorls are weakly beaded, and the umbilicus is almost closed. C. jujubinum tampaense Conrad (North Carolina to both sides of Flor- ida to Yucatan) varies in spire angle from 50 to 65 degrees, is not always so swollen at its periphery, and has 9 to 10 well-beaded spiral threads between each suture. Calliostoma occidentale Mighels and Adams North Atlantic Top-shell Nova Scotia to Cape Cod, Massachusetts. Europe. % inch in length, equally wide. Whorls convex and with 3 to 4 strong spiral cords, the 2 lower ones smooth, the upper one beaded. Color pearly- white. No umbilicus. Outer lip fragile. Moderately common from ro to 365 fathoms. Calliostoma bairdi Verrill and Smith Baird’s Top-shell Plate 3—o Massachusetts to North Carolina (and to Florida). 1 to 1% inches in length, about as wide. Angle of spire about 70 degrees. Sides of spire straight to slightly convex. Base rather flat. Periphery angular. Sculpture of 6 to 7 spiral rows of small, neat beads, with those on the top- most row being the largest. Suture difficult to find. No umbilicus. Color brownish cream with faint maculations of light reddish. Not uncommon from 43 to 250 fathoms. C. bairdi psyche Dall (North Carolina to Key West, 30 to 130 fathoms) is usually 4 inch in length, slightly wider, with a spire angle of about 75 to 80 degrees, and the color is lighter and more pearly. Base with 3 or 4 spiral brown lines. It has a chink-like depression beside the umbilicus. Uncommon. C. subumbilicatum Dall is a form of this species whose umbilicus is half open. Calliostoma tricolor Gabb Three-colored Top-shell Figure 33e Moss Beach, California, to Cape San Lucas, Mexico. 114 American Seashells Ficure 33. Pacific Calliostoma. a, gloriosum Dall; b, variegatum Cpr.; ¢, splendens Cpr.; d, gemmulatum Cpr.; e, tricolor Gabb; f, annulatum Sol.; g, ligatum Gld. (costatum); h, canaliculatum. All about natural size. (From Dall 1901.) PraTE | — THE FIVE CLASSES OF MOLLUSKS GASTROPODA PELECYPODA (a) Turnip Whelk, p. 237. (b) Calico Clam, p. 416. CEPHALOPODA (c) Paper Nautilus, p. 485. AMPHINEURA SCAPHOPODA (d) West Indian Chiton, p. 324. (e) Dall’s Pacific Tusk, p. 327. PLATE 2 PACIFIC COAST ABALONES Rep ABALONE, Haliotis rufescens Swainson, 10 to 12 inches. Left, artific- ially polished; right, natural (Northern California to Mexico), p. 92. GREEN ABALONE, H. fulgens Philippi, 7 to 8 inches. Left, exterior; right, interior (California to Mexico), p. 93. Pink ABALONE, H. corrugata Gray, 5 to 7 inches ‘Monterey, California to Mexico), p. 93. THREADED ABALONE, HZ, assimilis Dall, 4 to 5 inches (California), p. 93. JAPANESE ABALONE, H1. kamtschatkana Jonas, 4 to 6 inches (Japan, southern Alaska to northern California), p. 94. Brack ABALONE, H. cracherodi Leach, 4 to 6 inches (California to Mexico), p: 92. PLATE 3 TURBANS, TOP-SHELLS, STAR-SHELLS CHANNELED ‘TurRBAN, Turbo canaliculatus Hermann, 2 inches (South- eastern Florida and the West Indies), p. 123. SUPERB GAzA, Gaza superba Dall. 1 inch (Gulf of Mexico), p. 118. Barrp’s Spiny MarcaritE, Lischkeia bairdi Dall, 2 inches (Pacific Coast), p. 109. ADANSON’S PLEUROTOMARIA, Perotrochus adansonianus Crosse and Fischer, 3 inches (West Indies), p. 92. GREENISH TuRBAN, Astraea olivacea Wood, 114 inches (Gulf of Califor- nia), not in text. QuEEN TrEcuLa, Tegula regina Stearns, 114 inches (Southern California), De20: CuestNnut Tursan, Turbo castaneus Gmelin, 114 inches (Southeastern United States and the West Indies), p. 123. CARVED STAR-SHELL, Astraea caelata Gmelin, 2 inches (Southeastern United States and the West Indies), p. 124. AMERICAN STAR-SHELL, Astraea americana Gmelin, 14 inches (South- eastern Florida), p. 124. GREEN STAR-SHELL, Astraea tuber Linné, 114 inches (Southeastern United States and the West Indies), p. 124. . and m. LOonG-spINED STAR-SHELL, Astraea longispina Lamarck, 2 inches (Southeastern United States and the West Indies), p. 123. SHORT-SPINED STAR-SHELL, Astraea brevispina Lamarck, 2 inches (West Indies only), p. 123. CHOCOLATE-LINED Top-sHELL, Calliostoma zonamestum A. Adams, | inch (Florida Keys and the West Indies), p. 112. Bairp’s ‘Tor-sHELL, Calliostoma bairdi Verrill and Smith, 1 inch (Massachusetts to Florida), p. 113. Juyuse Top-sHELt, Calliostoma jujubinum Gmelin, 1 inch (Florida Keys and the West Indies), p. 113. CHANNELED Top-sHELL, Calliostoma canaliculatum Solander 1786, 1 inch (Pacific Coast), p. 115. PLATE 4 NERITES, PURPLE SEA-SNAILS, SUN-DIALS BLEEDING Tootn, Nerita peloronta Linné, | inch (Southeastern Florida and the West Indies), p. 128. Four-TooTHED NeEriITE, Nerita versicolor Gmelin, 34 inch (Florida and the West Indies), p. 128. ANTILLEAN NERITE, Nerita fulgurans Gmelin, 34 inch (Southeastern Florida and the West Indies), p. 129. RouGH-RIBBED NERITE, Nerita scabricosta Lamarck, 1 inch (Pacific side of Central America), not in text. ZEBRA NERITE, Puperita pupa Linné, 4 inch (Southeastern Florida and the West Indies), p. 129. TESSELLATE NERITE, Nerita tessellata Gmelin, 34 inch (Southeastern United States and the West Indies), p. 128. OutveE NeriTE, Neritina reclivata Say, 14 inch (Southeastern United States and the West Indies), p. 129. EMERALD NERITE, Smaragdia viridis Linné, Y4 inch (Southeastern Florida and the West Indies), p. 130. Vircin NeEriTE, Neritina virginea Linné, 1% inch, 6 color phases (Southeastern United States and the West Indies), p. 129. CoMMON PurRPLE SEA-SNAIL, Janthina janthina Linné, 1 inch (Pelagic, warm seas), p. 160. GLOBE PuRPLE SEA-SNAIL, Janthina globosa Swainson, 34 inch (Pelagic, warm seas), p. 160. Dwarr Purple SEa-sNAIL, Janthina exigua Lamarck, 14 inch (Pelagic, warm seas), p. 160. ComMMon) Sun-DIAL, Architectonica nobilis Roding, 114 inches (Southeastern United States and the West Indies), p. 142. KEELED SuN-DIAL, Architectonica peracuta Dall, 34 inch (Southeastern Florida and the West Indies), p. 143. Kreps’ SuN-DIAL, Architectonica krebsi Morch, 4% inch (Southeastern United States and the West Indies), p. 143. HeEnperson’s Niso, Niso hendersoni Bartsch 1953, 1 inch (Southeastern United States), not in text, Holotype. Giant ATLANTIC PyramM, Pyramidella dolabrata Lamarck, 1 inch (Bahamas and the West Indies), p. 289. FLAMINGO ‘TonGUE, Cyphoma gibbosum Linné, 34 inch (Southeastern United States and the West Indies), p. 183. Also see plate 8. McGinty’s Cypooma, Cyphoma mcgintyi Pilsbry, 34 inch (Florida), p. 1S. FINGERPRINT CypHoMa, Cyphoma signatum Pilsbry and McGinty, | inch (Florida), p. 184. 10 Tr PEATEs CONCHS, TRITONS, AND MOON-SHELLS Woop’s PANAMA Concu, Strombus granulatus Wood, 21% inches (Gulf of California to Panama), not in text. ATLANTIC CARRIER-SHELL, Xenophora conchyliophora Born, 2 inches (Southeastern United States and the West Indies), p. 173. Hawk-winc Concu, Sirombus raninus Gmelin, 3 inches (Southeastern Florida and the West Indies), p. 175. ANGULAR TRITON, Cymatium femorale Linné, 6 inches (Southeastern Florida and the West Indies), p. 195. RoosTER-TAIL Concu, Strombus gallus Linné, 5 inches (Southeastern Florida and the West Indies), p. 175. TrumMeer ‘Triton, Charonia tritonis nobilis Conrad, 14 _ inches (Southeastern Florida and the West Indies), p. 196. West InpiAn FicHtTinG Concu, Strombus pugilis Linné, 3 inches (Southeastern Florida and the West Indies), p. 173. FLoripA Ficutinc Concu, Strombus alatus Gmelin, 3 inches (Atlantic Coast from North Carolina to Texas), p. 174. PANAMA FIGHTING Concu, Strombus gracilior Sowerby, 3 inches (Gulf of California to Panama), not in text. Brown Moon-suELL, Polinices brunneus Link, 114 inches, (Southeastern Florida and the West Indies), p. 186. SHARK Eye, Polinices duplicatus Say, 2 inches (Atlantic Coast), p. 186. CoLorruL ATLanTic Natica, Natica canrena Linné, 1% _ inches (Southeastern United States and the West Indies), p. 191. ExcavaTED Natica, Stigmaulax elenae Recluz, 114 inches (Pacific side of Panama), not in text. @) Ge PLATE. 6 COWRIES ATLANTIC YELLOW CowriE, Cypraea spurca acicularis Gmelin, 1 inch (Florida and the West Indies), p. 180. CHESTNUT CowriE, Cypraea spadicea Swainson, 2 inches (Southern California), p. 181. ATLANTIC GRAY CowriE, Cypraea cinerea Gmelin, | inch (Southeastern Florida and the West Indies), p. 180. MEAsLED Cowrik, Cypraea zebra Linné, 3 inches (Southeastern Florida and the West Indies), p. 180. MousE Cowrik, Cypraea mus Linné, 2 inches (Southern Caribbean), ps lol: ATLANTIC DEER CowriE, Cypraea cervus Linné, 4 inches (South half of Florida and Cuba), p. 180. Young stage of the ATLANTIC DEER CowriE before the outer lip has become thickened and reinforced with teeth, p. 180. b. d. PLATE 7 SEA-WHIP SNAILS Common West InpIAN StmNiA, Neosimnia acicularis Lam., 1% inch. Yellow phase on Yellow Sea-whip, Leptogorgia virgulata Lam., and lavender phase on Purple Sea-whip, Leptogorgia hebes Verrill (North Carolina to the West Indies), p. 182. and c. CALIFORNIAN PEpIcULARIA, Pedicularia californica Newcomb, 14 inch. Attached to the hydrocoralline, Allopora californica Verrill. c is the heavy form, ovuliformis Berry (Southern California) p. 182. DecussaATE PepicuLariA, Pedicularia decussata Gould, 4% inch (Georgia to the West Indies), p. 181. SINGLE-TooTHED SIMNIA, Neosimnia uniplicata Sby., 4 inch (Virginia to the West Indies), p. 182. DA.LL’s TREASURED SIMNIA, Neosimnia piragua Dall, 1 inch. Holotype (West Indies), p. 182. WESTERN Cxuspsy SiMNiA, Neosimnia avena Sby., 1% inch (Monterey, California, to Panama), p. 183. INFLEXED SrmnNiA, Neosimnia inflexa Sby., 4 inch (Monterey, California, to Panama), p. 183. LorBBEcK’s Simnia, Neosimnia loebbeckeana Weink., 34 inch (Monterey, California, to Gulf of California, form barbarensis Dall), Oh lrexa)s PANAMA CypHoma, Cyphoma emarginata Sby., (4 specimens), 1 inch (Lower California to Panama), not in text. PLATE 8 Living Flamingo Tongues on the Rough Sea-whip, Muricea muricata Pallas. Upper right: McGinry’s CypHoma, Cyphoma mcgintyi Pilsbry, 1 inch (Southeastern Florida), p. 184. Lower Three: FLaminco Toncur, Cyphoma gibbosum Linné, | inch (North Carolina to West Indies), p. 183. PLATE 9 BONNETS, TUNS AND FROG-SHELLS RouGH PANAMA HELMET, Cypraecassis coarctata Wood, 3 inches (Gulf of California, south), not in text. LarGE PANAMA HELMET, Cypraecassis tenuis Wood, 5 inches (Pacific side of Panama), not in text. RETICUATED CowRIE-HELMET, Cypraecassis testiculus L., 3 inches (Florida, south), p. 194. ATLANTIC PARTRIDGE Tun, Tonna maculosa Dill., 3 inches (Southeastern Florida and the West Indies), p. 199. ScotcH Bonnet, Phalium granulatum Born, 3 inches (North Carolina to the West Indies), p. 192. SmMootH ScotTcH Bonnet, Phalium cicatricosum Gmelin, 2. inches (Southeastern Florida and the Caribbean), p. 193. Pear WHELK, Busycon spiratum Lam., 4 inches (North Carolina to Mexico), p. 236. Roya Bonnet, Sconsia striata Lam., 214 inches (Gulf of Mexico, south), polo2 Common Fic SHELL, Ficus communis Réding, 3 inches (North Carolina to Gulf States), p. 200. Doc Heap Triton, Cymatium cynocephalum Lam., 2 inches (Southeastern Florida and West Indies), p. 196. Gaupy FrocG-sHeLL, Bursa corrugata Perry, 3 inches (Southeastern Florida, south; Lower California to Ecuador), p. 198. ATLANTIC Hairy ‘Triton, Cymatium martinianum Orb., 24% inches (North Carolina to the West Indies), p. 195. a. b. d. ge m. nl. PLATE 10 MUREX SHELLS AND ROYAL TYRIAN PURPLE West InpIAN Murex, Murex brevifrons Lam., 4 inches (Southeastern Florida and the West Indies), p. 203. G1ANT EASTERN Murex, Murex fulvescens Sby., 6 inches (North Carolina torWexas),/ pp.) 203: RecaL Murex, Murex regius Swainson, 6 inches (Gulf of California to Panama), not in text. Brau’s Murex, Murex beaut Fischer and Bern., 4 inches (Gulf of Mexico and the West Indies), p. 202. Lace Murex, Murex florifer Reeve, 3 inches (Florida and the West Indies), p. 203. ANTILLEAN Murex, Murex antillarum Hinds, 3 inches (West Indies) not in text. Beau’s Murex, Murex beaui F. and B., 5 inches. Deep-water form (Florida and West Indies), p. 202. Casrit’s Murex, Murex cabriti Bernardi, 2 inches (Florida and the West Indies), p. 201. BANDED Dyke Murex, Murex trunculus L., 3 inches (Mediterranean Sea), p-- lz: SPINY DyE Murex, Murex brandaris L., 3 inches (Mediterranean Sea and West Africa), p. 12. CapBaGE Murex, Murex brassica Lam., 7 inches (West Mexico), not iA eCeX te AppLeE Murex, Murex pomum Gmelin, 3 inches (North Carolina to the West Indies), p. 202. PINK-MOUTHED Murex, Murex erythrostomus Swainson, 6 inches (Gulf of California to Panama), not in text. to q. Strips of paper dyed with Royal Tyrian Purple from the Mediterranean Sea and France. Various shades were obtained by the ancients by varying the concentration of snail dye, the number of dips and the species of snail. n. Light dipping from Murex trun- culus. 0. Light dipping from Murex brandaris. p. Heavy concentrat- ion from Murex brandaris and Thais haemastoma. q. Frequent dips ina heavy bath from Murex trunculus and Thais lapillus (see p. 12). gg — =) m. Nn. PLATE. 11 SPINDLES, DWARF OLIVES AND MARGINELLAS Brown-LineD Latirus, Latirus infundibulum Gmelin, 3 inches (Florida, Keys and West Indies), p. 241. McGinty’s Latirus, Latirus mcgintyi Pils., 2 inches (Southeastern Florida), p. 241: ORNAMENTED SPINDLE, Fusinus eucosmius Dall., 3 inches (Gulf of Mexico), p: 243: Cuestnut Latirus, Leucozonia nassa Gmelin, 114 inches (Florida to ‘Texas, south), p. 240. WhiTE-spoTTED Latirus, Leucozonia ocellata Gmelin, 1 inch (West Florida to West Indies), p. 241. SHORT-TAILED Latirus, Latirus brevicaudatus Reeve, 2 inches (Florida, Keys and West Indies), p. 241. ‘Turnip SPINDLE, Fusinus timessus Dall, 3 inches (Gulf of Mexico), Pu 24oe . and j. Wesr InpiAN Dwarr OLIvE, Olivella nivea Gmelin, 4 inch (Southeastern Florida and West Indies), p. 246. Jaseer Dwarr Otive, Olivella jaspidea Gmelin, 1/3 inch (Southeastern Florida and West Indies), p. 246. ORANGE MarGINELLA, Prunum carneum Storer, 34 inch (Southeastern Florida and West Indies), p. 254. RoyaL MarGINnELLA, Prunum labiatum Kiener, 1 inch (off Yucatan, Mexico, south), p. 256. WHITE-SPOTTED MarGINELLA, Prunum = guttatum Dill., 34 inch (Southeastern Florida and West Indies), p. 256. : Common ATLANTIC MARGINELLA, Prunum apicinum Menke, 4 inch (North Carolina to ‘Texas and West Indies), p. 257. ROOSEVELT’S MARGINELLA, Prunum roosevelti Btsch, and Rehd., 1 inch, holotype (Bahamas), p. 254. ORANGE-BANDED MARGINELLA, Hyalina avena Val., 1/3; inch (North Carolina to West Indies), p. 258. b. d. PLATE 12 OLIVE SHELLS LETTERED OLIvE, Oliva sayana Ravenel, 2'4 inches (North Carolina to the Gulf States), p. 245. PANAMA FALSE OLIVE, Agaronia testacea Lam., 2 inches (West Central America), not in text. Netrep Onive, Oliva reticularis Lam., 114 inches (Southeastern Florida and West Indies), p. 245. ANGULATE OLIVE, Oliva incrassata Solander, 2 inches (Gulf of California foe Peru) not Im fext:. Tent Otive, Oliva porphyria L., 3 inches (Gulf of California), not LN Scext. Potpast OLivE, Oliva polpasta Duclos, 14% inches (West Mexico), NOt um text: SPLENDID OLIVE, Oliva splendidula Sby., 2 inches (Panama), not in text. VEINED OLIVE, Oliva spicata Roding, 2 inches (Lower California to Panama), not in text. PureLE Dwarr OnIve, Olivella biplicata Sby., 1 inch (Washington to Lower California), p. 247. gg h. n. PLATE 13 ATLANTIC TULIPS, SPINDLES AND VOLUTES I'LoripA HorsrE Concu, Pleuroploca gigantea Kiener, 3 inches (young) (North Carolina to Florida). For adult see pl. 23y, p. 242. ‘TRuE Tuuip, Fasciolaria tulipa L., 4 inches (North Carolina to the West Indies), p. 242. BANDED Tuite, Fasciolaria hunteria Perry, 3 inches (North Carolina to Gulf States), p. 242. Couer’s SPINDLE, Fusinus couei Petit, 4 inches (off Yucatan, Mexico), not in text. Scumitt’s Voture, Scaphella schmitti Bartsch, 5 inches. Holotype (off south Florida), p. 251. Junonia, Scaphella junonia Shaw, 5 inches (North Carolina to Texas), p2b0: Common Music Vo.uTe, Voluta musica L., 2 inches (West Indies), p. 250. PLAME TrreEgBRA, Terebra taurina Solander, 5 inches (Florida, the Gulf and West Indies), p. 265. Royat Froripa Mirer, Mitra florida Gould, 114 inches (Florida and West Indies), p. 248. Donrn’s Voture, Scaphella dohrni Sby., form florida Cl. and Ag., 3 inches (off Florida and Cuba), p. 251. Common Nurmec, Cancellaria reticulata L., 144 inches (North Carolina to Florida), p. 252. Waite GIANT ‘TurRET, Polystira albida Perry, 4 inches (off Florida, the Gulf of Mexico and West Indies), p. 268. DELICATE GriAnT TurRRET, Polystira tellea Dall, 3 inches (off South- eastern Florida), p. 268. Latirus-LIKE VASE, Vasum (Siphovasum) latiriforme Rehd. and Abb. 1951. 2 inches. Holotype (off Yucatan, Mexico), not in text. MINIATURE ‘TRITON ‘TRUMPET, Pisania pusio L.., 14% inches (Florida and West Indies), p. 233. STRIATE Busse, Bulla striata Brug., 1 inch (Gulf of Mexico, south), pets BROWN-LINED PAPER-BUBBLE, Hydatina vesicaria Solander, | inch (Florida and West Indies), p. 276. d. mM. O. p: PLATE 14 ATLANYTIG CONES Carrot Cone, Conus daucus Hwass, 114 inches (Florida and West Indies), p. 260. Junia’s Cone, Conus juliae Clench, 11% inches (off south Florida), p. 261. Sozon’s Cone, Conus sozoni Bartsch, 3 inches (South Carolina to Gulf of Mexico); p: 260k Froripa Cone, Conus floridanus Gabb, 114 inches (North Carolina to Florida), p. 261. Dark FroripA Cone, C. floridanus floridensis Sby (North Carolina to Florida), p. 261. VILLEPIN’S Cone, Conus villepini F. and B. 1!4 inches (Gulf of Mexico), ps 203: GOLDEN-BANDED CONE, Conus aureofasciatus Rehder and Abbot, 3 inches (Gulf of Mexico), p. 260. SENNOTT’S CONE, Conus sennottorum Rehd. and Abb., 1 inch (Gulf of Mexico), p. 261. Criark’s Cone, Conus clarki Rehd. and Abb., 1 inch (off Louisiana), pa 204. STIMPSON’S CONE, Conus stimpsont Dall, 114 inches (Gulf of Mexico), Dhe AOE Maze’s Cone, Conus mazei Desh., 2 inches (Gulf of Mexico and West indies); =p. 264, GLORY-OF-THE-ATLANTIC Cone, Conus granulatus L., 2 inches (South- eastern Florida, south), p. 264. CROWN Cone, Conus regius Gmelin, 3 inches (Florida and West Indies), py 2oz. JAspER Cone, Conus jaspideus Gmelin, 34 inch (Florida and West Indies), p. 262. Mouskr Cone, Conus mus Hwass, 1 inch (Southeastern Florida and West Indies), p. 262. ALPHABET CONE, Conus spurius atlanticus Cl., 3 inches (Florida and Gulf of Mexico), p. 260. PLATE 15 NEW ENGLAND NUDIBRANCHS RED-FINGERED Eouis, Coryphella rufibranchialis Johnston, | inch (Arctic to New York), p. 310. PrLost Doris, Acanthodoris pilosa Abild., 1 inch (Arctic to Connecticut; Alaska), p. 305. DwarF BALLoon Eouts, Eubranchus exiguus A. and H., 1/5; inch (Arctic to Massachusetts), p. 309. Jounston’s BALLOON Eouis, Tergipes despectus Johnston, 1/3 inch (Arctic to New York), p. 309. Fronp Eouis, Dendronotus frondosus Ascanius, 2 inches (Arctic to Rhode Island; to Washington), p. 307. ATLANTIC ANcULA, Ancula cristata Alder, % inch (Arctic to Massachusetts), p. 306. PapiLLose Eouis, Aeolis papillosa L., 2 inches (Arctic to Rhode Island; to California), p. 308. PAYNTED BALLOON Eouts, Eubranchus pallidus A. and H., 14 inch (Arctic to Boston), p. 310. YELLOW FatsE Doris, Adalaria proxima A. and H., 14 inch (Arctic to Maine), p. 306. ORANGE-TIPPED Eouis, Catriona aurantia A. and H., 14 inch (Arctic to Connecticut), p. 308. PLATE 16 PACIFIC COAST NUDIBRANCHS Hopkins Doris, Hopkinsia rosacea MacFarland, | inch (Monterey to San Pedro, California), p. 307. MacFartanp’s Grand Doris, Triopha grandis MacFarland, 3 inches (California), p. 304. Nose Paciric Doris, Archidoris nobilis MacF., 4 inches (California), p00: San Dieco Doris, Diaulula sandiegensis Cooper, 24% inches (Alaska to California), p. 301. ORANGE-SPIKED Doris, Polycera atra MacF¥., 34 inch (California), p. 305. MacutatrepD Doris, Triopha maculata MacF¥., | inch (California), p. 304. MacFarianp’s Pretrry Doris, Rostanga pulchra MacF¥., 34 inch (California), p. 300. MonterEY Doris, Archidoris montereyensis Cooper, 114 inches (California), p. 299. Heatu’s Doris, Discodoris heathi MacF., 1 inch (California), p. 300. Laita Doris, Laila cockerellt MacF¥., 34 inch (California), p. 304. CARPENTER’S Doris, Triopha carpenteri Stearns, 1 inch (California), p»s04. Porter's BuiuE Doris, Glossodoris porterae Cockerell, 4% inch (California), p. 303. TROCHIDAE 115 %4 to 1 inch in length, heavy for its size; whorls angular, with the upper third slightly concave to flat and the somewhat angular periphery flattish. Early whorls with minutely beaded threads, later whorls with fine, smooth- ish cords of various sizes. Nucleus tan to whitish. Color yellowish brown with a few spiral lines of alternating brown and white bars. Sometimes axially variegated. Dredged just offshore from 8 to 35 fathoms. Moderately com- mon. Calliostoma gemmulatum Carpenter Gem Top-shell Figure 33d Cayucos, California, to the Gulf of California. %4 inch in length, not as wide; characterized by its dark gray-green color and two extra-strong, beaded spiral cords. There are also 3 or 4 minor cords that are not so heavily beaded. Nucleus dark-tan. Moderately common in the littoral zone on rocks and wharf pilings. Calliostoma supragranosum Carpenter Granulose Top-shell Plate 18s Monterey, California, to Lower California. ¥% inch in length, solid, glossy; characterized by numerous, fine, spiral cords which are sometimes weakly beaded, and by a wide, rather flattish pe- riphery. Nucleus tan. Color light yellowish brown, commonly with a spiral row of subdued white spots at the lower periphery. Interior brightly nacre- ous. Moderately common on rocks at low tide. Calliostoma annulatum Solander Ringed Top-shell Figure 33f Alaska to San Diego, California. 1 to 1% inch in length, not quite so wide; characterized by its light weight, golden-yellow color with a mauve band at the periphery, and by the numerous, spiral rows of tiny, distinct beads (5 to 9 rows in the spire whorls). Nucleus pink. Dredged offshore and occasionally washed ashore. Formerly C. annulatum Martyn. Calliostoma canaliculatum Solander 1786 Channeled Top-shell Plate 3q; figure 33h Alaska to San Diego, California. 1 to 1¥% inches in length, not heavy, sides of whorl flat. Periphery of the last whorl sharp. Base of shell almost flat. Characterized by sharp, promi- nant, slightly beaded, spiral cords. Color yellowish tan. Nuclear whorls white. Moderately common offshore. Found on floating kelp weed. For- merly known as C, canaliculatum Martyn, and doliarium Holten 1802. 116 American Seashells Calliostoma variegatum Carpenter Variable Top-shell Figure 33b Alaska to southern California. 1 inch in length, similar to doliarium, but with smaller cords which are strongly beaded; nucleus pink; the sides of the spire slightly concave, and the periphery of the last whorl rounded. Uncommonly dredged in 15 to 400 fathoms. Calliostoma gloriosum Dall Glorious Top-shell Figure 33a San Francisco to San Diego, California. 1 inch in length, not quite so wide, rather light, with about ro fine, spiral threads between sutures. The upper 5 are inclined to be minutely beaded. Periphery of last whorl moderately sharp. Columella white, fairly thick and with a swelling at the lower 7%. Nuclear whorls white. Color of shell yellow- ish brown with darker purplish brown, slanting and rather elongate spots arranged in 2 spiral series, Moderately common in shallow water. Calliostoma splendens Carpenter Splendid ‘Top-shell Figure 33¢ Monterey to Lower California. % to 7% inch in length, equally wide, with about 5 to 6 whorls which bear between sutures 5 strong spiral cords. The upper 2 or 3 are finely beaded, the lower 2 or 3 are smooth and cord-like. Between the cords, the shell is brilliant orange-iridescent. General color a yellowish orange with large white maculations on the upper half of the whorls. Moderately com- mon offshore, uncommonly washed ashore. Calliostoma ligatum Gould Ribbed ‘Top-shell Figure 33g Alaska to San Diego, California. %4 to 1 inch in length, equally wide, rather heavy; whorls quite well rounded, characterized by smooth, spiral, light-tan cords (6 to 8 on the spire whorls) on a background of chocolate. Sometimes flushed with mauve. No umbilicus. Aperture usually pearly-white. A very common littoral species from northern California north, Formerly C. costatum Martyn. Subfamily GIBBULINAE Genus Livona Gray 1847 There is only one species © this genus, namely L. pica from the West TROCHIDAE LiL yi Indies. Although fairly good specimens are found without their soft parts in southern Florida and Bermuda, this species has been extinct in those areas for several hundred years. Living individuals may be found abundantly in the West Indies where they are used in chowders by some people. Cittariwm Philippi 1847 is this genus. Livona pica Linné West Indian Top-shell Figure 34 Southeast Florida (dead) and the West Indies (alive). 2 to 4 inches in length, heavy, rather rough, and with splotches of pur- plish black on dirty-white. Umbilicus round, narrof and very deep. Inner edge of lip with rich cobalt-blue mottlings. Operculum horny, large, round, multispiral and opalescent blue-green in life. Figure 34. West Indian Top-shell, Livona pica Linné. a, shell with animal ex- tended (3 inches); b, outline of head X2. (From Clench and Abbott 1943 in Johnsonia.) Genus Norrisia Bayle 1880 Norrisia norrisi Sowerby Norris Shell Plate 18m Monterey, California, to Lower California. 17% inches in length, slightly wider, heavy, smoothish with a glossy finish, especially on the underside. Lip sharp. Aperture thickened within and pearly. Umbilicus ovate, very deep, colored a greenish blue on the columellar side, bordered on the other side by glossy black-brown which fades into rich chestnut over the remainder of the shell. Operculum, multi- spiral, externally ornamented with spiral rows of dense bristles. Animal tinged with red. Moderately common among the kelp weed beds. 118 American Seashells Genus Gaza Watson 1879 Gaza superba Dall Superb Gaza Plate 3b Northern Gulf of Mexico to the West Indies. 1 to 1% inches in width. Spire somewhat elevated. Color old ivory with a golden sheen. Early whorls faintly wine-colored. Although formerly thought to be one of our rarest shells, it is now known to be relatively com- mon in the Gulf of Mexico in 50 or more fathoms. It is indeed a beautiful species. The rare Gaza (Callogaza Dall 1881) watsoni Dall from deep water in the West Indies is illustrated in figure 32a. Subfamily MONODONTINAE Genus Tegula Lesson 1832 Tegula fasciata Born Smooth Atlantic Tegula Plate 17p Southeast Florida and the West Indies. % to % inch in width. Surface smooth, color yellowish to brown, with a fine mottling of reds, browns and blacks; often with a narrow, pale, spiral band of color on the periphery. Under the lens, spiral rows of alternating red and white, short lines or dots may be seen. Some specimens may have zigzag white bands. Interior of deep, round, smooth umbilicus and the callus are white. Iwo teeth at the base of the columella. Thick adults may have small teeth just inside the lower margin of the aperture. Whorl may be slightly concave just below the suture. In the young only, the umbilicus has two deep spiral grooves. Moderately common under rocks at low tide. Tegula lividomaculata C. B. Adams West Indian Tegula Key West and the West Indies. %4 inch in width and about % inch in length. Top of whorls sculptured with about a dozen fairly regular, small, spiral cords. The angular periphery of the whorls bears the largest cord. Umbilicus round, deep, and furrowed on its sides by two spiral cords, the upper one ending at the columella in a fairly sizeable bead. Columella set back quite far at its upper half; the lower section bears the bead, and below that there are several, smaller, indistinct beads. Color of shell grayish to brownish white with small mottlings of reddish or blackish brown. Operculum, as in all Tegzla, horny and multi- spiral. Formerly scalaris Anton (not Brocchi) and indusi “Gmelin.” Com- mon under rocks in the West Indies, but uncommon on the Lower Florida Keys. TROCHIDAE 119 T. hotessierana Orbigny from the West Indies is similar, but rarely over ¥ inch, with a more rounded periphery, with smaller, neater, equal-sized, smooth spiral threads, and dark bluish black in color, except for a whitish area around the narrow umbilicus. Uncommon. Tegula excavata Lamarck Green-base Tegula Florida Keys? Caribbean area. ¥% inch in length and width. Characterized by its bluish-gray color, corrugated sculpture (weak spiral cords and oblique lines of growth), its concave base, thin outer lip, and especially by the blue-green to iridescent- green circle of color around the very deep, round, narrow umbilicus. A variant exists in some areas which lacks the green, umbilical color and in which the spiral cords are stronger and the shell with axial, slanting bars of black-brown. Very common in the West Indies, along the rocky shores. Tegula funebralis A. Adams Black Tegula Vancouver, B. C., to Lower California. 1 to 1% inches in length, heavy, dark purple-black in color; smoothish, but with a narrow, puckered band just below the suture. Weak spiral cords rarely evident; coarse growth lines present in large, more elongate specimens. Base rounded. Umbilicus closed or merely a slight dimple. Columella pearly, with two small nodules at the base. A very common littoral, rock- loving species. Do not confuse with T. gallina. Tegula gallina Forbes Speckled Tegula Plate 18v San Francisco to the Gulf of California. 1 to 1% inches in length, very similar to funebralis, but a lighter, gray- ish green color with dense, zigzag, axial stripes of purplish. The shell surface is also coarser. A common, southern species found among littoral rocks. Tegula brunnea Philippi Brown Tegula Crescent City to Santa Barbara Islands, California. 1 to 1% inches in length, similar to funebralis, but light chestnut-brown in color with the base often glossy, brownish white. The umbilicus is closed, but usually with a dimple-like impression. Columella usually with only one small tooth near the base. Common at dead low tide on rocks. Usually heavily encrusted with algal growths. 120 American Seashells Tegula aureotincta Forbes Gilded Tegula Plate 18k Southern third of California to Mexico. %4 to 1 inch in length, heavy; dark grayish to gray-green; characterized by a golden-yellow stain within the deep, round, narrow umbilicus, by the sky-blue band around the umbilicus, and by the 4 or 5 strong, smoothish, spiral cords on the periphery and the base. Top of whorls with weak, crude, slant- ing, axial wrinkles. A moderately common, littoral, rock-loving species. Tegula ligulata Menke Western Banded Tegula Plate 18h Monterey, California, to Acapulco, Mexico. %4 inch in length, heavy; whorls and spire convex. Umbilicus very deep, round and fairly narrow. Whorls with numerous, beaded, spiral cords. Outer lip sharp, but thickened and pearly within. Lower part of lip with about 8 small nodules opposite the spiral threads which run back into the aperture. Color rusty-brown with black flecks. Compare with awreotincta whose um- bilical area is stained with greenish blue and golden-yellow. A moderately common littoral, rock-dweller. Subgenus Chlorostoma Swainson 1840 Tegula regina Stearns Queen Tegula Plate 3f Catalina Island to the Gulf of California. 1 inches in length, slightly wider; 6 to 7 whorls, spire flat-sided; base slightly concave. With numerous slanting, small, axial cords. The crenulated periphery slightly overhangs the suture of the whorls below. Base with strong, arched lamellae. Color dark purplish gray. Umbilical region stained with bright golden-yellow. A rather rare and choice collector’s item secured by diving. It has also been washed ashore on Catalina Island. Subgenus Promartynia Dall 1909 Tegula pulligo Gmelin 1791 (marcida Gould) Dusky Tegula Plate 18y Alaska to Santa Barbara, California. 1 to 1% inches in length, slightly wider. Resembles brunnea, but has a deep, round umbilicus and a thin, rather sharp columella. It is also very similar to montereyi, but its whorls are more rounded and its umbilicus is more smoothly rounded and without the white color and faint spiral ridges found in montereyi. This species is doubtfully placed here and perhaps TURBINIDAE bt should be considered a typical Teguwla. Moderately common, especially in the north. Tegula montereyi Kiener Monterey Tegula Plate 18x Bolinas Bay, California, to Santa Barbara Island. 1 to 1% inches in length, about as wide. Conical in shape, with very flat-sided whorls and spire. Base almost flat. Surface smoothish, except for almost obsolete spiral threads. Umbilicus very deep, lined with 1 or 2 weak spiral cords. Columella arched, and with 1 prominent, pointed tooth. This rather rare species resembles a large Calliostoma. It is found on kelp in moderately deep waters. Family TURBINIDAE Subfamily LIOTIINAE The operculum in members of this subfamily is round, multispiral, and with a horny base on top of which are numerous rows of tiny calcareous beads. Genus Cyclostrema Marryat 1818 Cyclostrema cancellatum Marryat Cancellate Cyclostreme Southeast Florida, the Bahamas to Jamaica. ¥% inch in diameter, flat-topped, 4 whorls, opaque-white. Widely and deeply umbilicate. Axial sculpture of 15 to 17 rounded, low ribs which en- circle the entire whorl and are made nodulose in crossing the 12 smaller spiral cords. Periphery squarish, with a cord above, below and at the center. Rare from 1 to 17 fathoms. Cyclostrema is a neuter, not feminine, word. C. amabile Dall from Cuba to Barbados is much rarer and differs in being smaller, in having a thicker, more rounded lip, and in lacking axial cords on top of the whorls. 25 to 80 fathoms. Genus Liotia Gray 1847 Liotia bairdi Dall Baird’s Liotia Plate 17u North Carolina to Florida and Yucatan. % inch in length, not quite so wide; thick, rose in color. Whorls glo- bose, the last with about 10 spiral cords of tiny, prickly beads. Suture deeply channeled. Umbilicus very narrow and deep. Moderately common from 18 to 85 fathoms. 122 American Seashells Liotia fenestrata Carpenter Californian Liotia Plate 18u Monterey, California, to San Martin Island, Mexico. ¥%, inch in diameter; spire low, shell solid; deeply and narrowly umbili- cate. Aperture circular, pearly within. Ash-white in color. Characterized by heavy cancellate sculpturing which makes the shell appear pitted by rows of deep, squarish holes. Uncommonly dredged from 10 to 25 fathoms. L. cookeana Dall is not this species, as is commonly thought, but is a Cy clostrema. Genus Arene H. and A. Adams 1854 Arene cruentata Mihlfeld Star Arene Southeast Florida and the West Indies. ¥% inch in length, one third again as wide. 4 to 5 whorls angular with the periphery bearing a series of strong, triangular spines which are hollow on their anterior edges. Color white to cream with small, bright-red patches on top of the whorl. Below the main row of spines there is a minor spiral row of smaller spines. Suture channeled. Aperture circular, pearly within. Umbilicus round, deep, and bordered by 3 spiral, beaded cords. Uncom- mon under rocks. The form vanhbyningi Rehder from Sand Key, Key West, is pale gray- white with most red patches absent. It lacks fine, axial ridges on top of the whorl which are usually present in the typical form. Uncommon. Arene venustula Aguayo and Rehder (Miami to Puerto Rico) is similar to cruentata, but smaller, much more squat, chalky-white, and with two pe- ripheral rows of blunt spines. The rows are very close to each other. Rare, 20 fathoms. Arene gemma Yuomey and Holmes Gem Arene Plate 17q North Carolina to south half of Florida to Brazil. ¥% inch or less, turbinate in shape; 3 spiral rows of neat, tiny beads on the squarish periphery. Suture minutely channeled and bounded below by a spiral row of whitish beads. Top slope of whorls and base of shell flattish. Axial threads on entire shell microscopic and crowded. Umbilicus round, deep, bordered by 7 to 9 distinct beads. Color of shell white to tan with minute specklings of red and/or brown. Commonly dredged from 3 to 100 fathoms. a LURBINIDAE £23 Arene variabilis Dall Variable Arene Plate 17s North Carolina to southeast Florida and the West Indies. %16 inch in length, turbinate, similar to A. gemma, but pure white in color, with scale-like beads, suture more deeply channeled, and with a more rounded periphery. 12 very weak beads bordering the more open umbilicus. The 3 spiral rows of beads on the whorl may be almost smooth in some specimens. Very commonly dredged from 20 to 270 fathoms. Subfamily TURBININAE Genus Turbo Linné 1758 Turbo castaneus Gmelin Chestnut Turban Plate 3g North Carolina to Florida, Texas and the West Indies. 1 to 1% inches in length. Color orangish, greenish, brown or grayish, commonly banded with flame-like white spots. Aperture white. Callus on columella heavy. Lower lip projects downward. Operculum calcareous. The form named crenulatus Gmelin is merely less tuberculate. Section Taenioturbo Woodring 1928 Turbo canaliculatus Hermann Channeled Turban Plate 3a Lower Florida Keys and the West Indies. 2 to 3 inches in length. A deep smooth channel runs just below the suture. Surface glossy. 16 to 18 strong, spiral, smooth cords on body whorl. Aperture white. Umbilicus narrow. Operculum pale-brown inside with 3 to 4 whorls, and white, smoothish and convex on the outside. This is the hand- somest Turbo in the Western Atlantic, and considered a great rarity in American waters. Formerly T. spenglerianus Gmelin. Genus Astraea Roding 1798 Subgenus Astralium Link 1807 Astraea longispina Lamarck Long-spined Star-shell Plate 3k, m Southeast Florida and the West Indies. 2 to 2% inches in width; shell low, almost flat on its underside. Periph- ery of whorls with strong, flattened, triangular spines. Either with or without an umbilicus. Aperture silvery inside. A form which has an elevated spire and is more spinose (pl. 3m) was known as A. spinulosa Lamarck. Short-spined specimens of this species are often erroneously called A. brevi- 124 American Seashells spina Lamarck. The latter, however, is a distinct species from the West Indies which is characterized by a splotch of bright orange-red around the umbilical region (see pl. 31). Astraea americana Gmelin American Star-shell Plate 3i Southeast Florida. 1 to 1% inches in length, %4 as wide. Characterized by its sharp-angled spire, flat sides, white to cream color, and by the numerous, long, wavy, weak, axial ribs. Base of shell with 5 to 8 small, finely fimbriated, spiral cords, and a small ridge at the base of the columella which has about a dozen small axial ridges. Commonly found under rocks at low tide on the Lower Florida Keys. Operculum variable, but usually thick, convex and with a small or large dimple. The subspecies, imbricata Gmelin, from the West Indies has stronger, longer and fewer axial ribs which extend to the flat base of the shell and are hollow at their ends. The subspecies guadeloupensis Crosse from the Greater Antilles is intermediate between these two. Both moderately common at low water. Subgenus Lithopoma Gray 1850 Astraea caelata Gmelin Carved Star-shell Plate 3h Southeast Florida and the West Indies 2 to 3 inches in length and width. Similar to A. tuber, but with 9 to 10 spiral rows of numerous, hollow, scale-like spines on the lower 7% of the last whorl, 5 of which are on the base of the shell. Operculum thick, convex, and finely pustulose. Moderately common in the West Indies. Astraea tuber Linné Green Star-shell Plate 3] Southeast Florida and the West Indies. 1 to 2 inches in length, equally wide. Characterized by the peculiar green-and-white, cross-hatched color scheme, by the low, blunt, smooth axial ridges, and by the smoothish base of the shell. Sometimes mottled in soft browns. Common below low water in the West Indies, rare in Florida. Operculum with a thick, arched, tapering ridge on the exterior (like a large comma). Subgenus Pomaulax Gray 1850 Astraea undosa Wood Wavy Turban Plate 18p TURBINIDAE 125 Ventura, California, to Lower California. 2 to 3 inches in length, characterized by a strong, wavy, overhanging periphery, and by the dark-brown, fuzzy periostracum. Base concave, with 3 small, indistinct spiral cords. Outside of operculum with 3 strong, prickly ridges. Common in shallow water, especially around Todos Santos Bay, Lower California. Cc Figure 35. Astraea gibberosa Dillwyn, 2 inches. c, outer side of calcareous oper- culum; d, muscle attachment side. Subgenus Pachypoma Gray 1850 Astraea gibberosa Dillwyn Red Turban Figure 35 Vancouver, B. C., to San Diego, California. 17% to 3 inches in length, heavy, brick-red to reddish brown in color. Characterized by 5 to 6 strong, spiral cords on the flattish base. Operculum chitinous green on inner side; outer side swollen, smooth, enamel-white. Formerly A. inaequalis Martyn. Moderately common just offshore down to 40 fathoms. Genus Homalopoma Carpenter 1864 Shells small, turbinate in shape. Operculum calcareous, oval, thick; its exterior with a thick, paucispiral whorl. Underside of operculum convex with multispiral, chitinous whorling. Leptothyra Pease 1869 is this genus. Homalopoma albida Dall White Dwarf Turban Southeast Florida, Cuba to Yucatan. 126 American Seashells % inch in length, equally wide, very thick-shelled, resembling in shape a Margarites. Pure white in color. Whorls rounded, 5 to 6 in number, each bearing 5 to 6 strong, rounded, spiral cords, the lower 2 being below the periphery of the whorl. Aperture and parietal wall glossy, slightly opalescent. Columella arched, with a small tooth in the middle and a smaller one usually at the base. No umbilicus. Commonly dredged from 35 to 450 fathoms. H. linnei Dall from southeast Florida to Barbados has 8 smaller, beaded spiral cords on the upper part of the whorls and 10 on the base, otherwise it is very similar to albida. It is quite rare. Homalopoma carpenteri Pilsbry Carpenter’s Dwarf Turban Plate 18i Alaska to Lower California. %4 to % inch (5 to 9 mm.) in length, solid, globose. Pinkish red to brownish red in color. Last whorl and base with 15 to 20, evenly sized, smooth, spiral cords separated from each other by a space about half as wide as the cords. Base of pearly columella with 2 or 3 exceedingly weak nodules. A very common species frequently washed ashore and inhabited by small hermit crabs from Monterey to Mexico. Do not confuse with Jurida. Homalopoma lurida Dall Dark Dwarf Turban Puget Sound to Lower California. % inch (5 to 7 mm.) in length, similar to carpenteri, but half as large, black-brown in color, although occasionally whitish with red axial streaks. The spiral cords are usually fewer in number and more rounded. Moderately common in shallow water under rocks. Homalopoma bacula Carpenter Berry Dwarf Turban Puget Sound to Lower California. % inch or less in length, similar to carpenteri but with a flatter spire, and smoothish, except for numerous incised, spiral lines producing very weak threads. Color dark, rosy-brown. A moderately common shallow-water species, sometimes found with carpenteri. A thorough anatomical and life history study of this genus is needed to ascertain the validity of these species. Family PHASIANELLIDAE Genus Tricolia Risso 1826 Tricolia affinis C. B. Adams Checkered Pheasant PHASIANELLIDAE 127 Lower Florida Keys and the West Indies. ¥ to % inch in length, moderately elongate, smoothish except for mi- croscopic spiral grooves in some specimens. Color rose to brownish, some- times whitish. Always with numerous small dots of pink, orange or a brown- ish color. Frequently with zigzag, axial bars of rose or brownish yellow. Often with irregular small spots or blotches of opaque-white. Umbilicus slit-like. Moderately common. T. concinna C. B. Adams is probably the same. Tricolia tessellata Pot. and Mich. from the West Indies is somewhat the same, but it is characterized by distinct, revolving lines of orange or red that descend obliquely over the whorls. Common. Tricolia pulchella C. B. Adams Shouldered Pheasant Plate 17r Southeast Florida and the West Indies. ¥g inch in length, spiral sculpture of numerous very small spiral cords, the largest being at the periphery of the whorl, thus giving the shell a slightly carinate shape. This carina is more pronounced in the early whorls and commonly bears a spiral row of tiny, white dots. Color variable, usually whitish gray with pink or brown axial mottlings and irregularly placed tiny dots of rose, yellow-brown or purplish brown. Umbilicus a mere chink. Operculum calcareous, convex, half smooth, the other half with fine, arched riblets. Common in shallow water among dead corals. Tricolia compta Gould Californian Banded Pheasant Crescent City, California, to the Gulf of California. % to %% inch in length, resembling a moderately high-spired Littorina, but distinguished from that genus by its calcareous operculum. Shell smooth, in life covered by a thin gray-green, translucent periostracum. Characterized by the numerous, spiral lines of blackish green, red, brown or purplish which slant slightly downward, so that they are not parallel to the suture. Axial zigzag, wider bands are also present. Very abundant on eel-grass in shallow bays. Frequently washed ashore. Genus Eulithidium Pilsbry 1898 Eulithidium rubrilineatum Strong Miniature Pheasant Monterey to Lower California. % 6 inch in length, depressed turbinate in shape, with 4 to 5 whorls. Char- 128 American Seashells acterized by its very small size, and by about a dozen obliquely set, spiral bright-red lines. The top of the whorls may be solid red and with large, opaque-white spots. Umbilicus a mere chink-like depression. Operculum calcareous and white. Tricolia variegata Carpenter is the same (not Lamarck). Common among weeds in tidepools and among kelps offshore. Family NERITIDAE Genus Nerita Linné 1758 Nerita peloronta Linné Bleeding Tooth Plate 4a Southeast Florida, Bermuda and the West Indies. %4 to 1% inches in length; grayish yellow with zigzags of black and red. Characterized by the blood-red parietal area which bears 1 or 2 whitish teeth. Operculum: underside coral-pink; one half of outer side smooth and dark-orange, other half smoothish or papillose and brownish green. Very abundant along the rocky shores facing the open ocean. It is a popular souvenir. Nerita versicolor Gmelin Four-toothed Nerite Plate 4b South 34 of Florida and the West Indies. Bermuda. %4 to 1 inch in length; dirty-white with irregular spots of black and red arranged in spiral rows; spirally grooved; outer lip spotted with red, white and black on margin. Parietal area slightly convex, white to yellowish and with 4 (rarely 5) strong teeth. Operculum: exterior brownish gray, finely papillose and slightly concave. Commonly associated with N. peloronta. Nerita variegata Karsten (1789) is invalid, since it appears in a non-binomial work. Nerita tessellata Gmelin Tessellate Nerite Plate 4f Florida to Texas, the West Indies and Bermuda. % inch in length, irregularly spotted with black and white, sometimes heavily mottled; coarsely sculptured with spiral cords of varying sizes. Parietal area concave, bluish-white and bearing 2 weak teeth in the middle. Operculum: exterior slightly convex, black in color. Commonly congregate in large numbers under rocks at low tide. Rare in northern Florida. Do not confuse with N. fulgurans Gmelin whose operculum is bluish white to yel- lowish gray, not black. NERITIDAE 129 Nerita fulgurans Gmelin Antillean Nerite Plate 4c Southeast Florida, the West Indies and Bermuda. %4 to 1 inch in length, very similar to N. tessellata, but with a lighter- colored, yellowish gray operculum. The spiral ridges on the shell are more numerous, the color patterns blurred, the aperture relatively wider, and the teeth more prominent. This is a salt to brackish-water inhabitant of pro- tected shores, and is abundant only in certain restricted localities. It is seldom represented or properly labeled in private collections. Genus Puperita Gray 1857 Puperita pupa Linné Zebra Nerite Plate ge Southeast Florida and the West Indies. ¥, to % inch in length, thin, smooth, chalky-white with black, axial, zebra-like stripes. Aperture and smooth operculum light-yellow. Lives in small, placid pools above the high-water mark. Common in the West Indies, rare in Florida. Genus Neritina Lamarck 1816 Subgenus Vitta Morch 1852 Neritina virginea Linné Virgin Nerite Plate 41 Florida to Texas, the West Indies and Bermuda. % inch in length, smooth, glossy, very variable in color pattern and shades—blacks, browns, purples, reds, whites, olive—crooked lines, dots, mottlings, zebra-like stripes and sometimes spirally banded. Parietal area smooth, convex, white to yellow, and with a variable number of small, irregular teeth. Operculum usually black. A very common, widespread inhabitant of intertidal, brackish-water flats. Neritina reclivata Say Olive Nerite Plate 4g Florida to Texas and the West Indies. ¥% inch in length, glossy, often with the spire eroded away. Ground color brownish green, olive or brownish yellow with numerous axial lines of black-brown or lavender. Operculum black to slightly brownish. Com- mon in brackish water and also found in fresh-water springs near the seashore in Florida. A globose form or subspecies (?) with a short spire and more convex whorls replaces the higher-spired, typical form from Texas to Panama, but 130 American Seashells may also appear in eastern Florida. It has been named floridana Reeve 1855, rotundata von Martens 1865 and sphaera Pilsbry 1931. Genus Smaragdia Issel 1869 Smaragdia viridis Linné Emerald Nerite Plate gh Southeast Florida, the West Indies and Bermuda. ¥% to ¥% inch in length, glossy, smooth, pea-green, often with tiny chalk- whice bars and rarely with purplish brown, narrow, zigzag bars. True viridis comes from the Mediterranean. Some workers separate our form as the subspecies viridemaris Maury 1917. N. weyssei Russell 1940 is a synonym. Order MESOGASTROPODA Superfamily LITTORINACEA Family LACUNIDAE Genus Lacuna Turton 1827 Rather fragile, smooth periwinkles characterized by a shelf-like colu- mella and a chink-like umbilicus. Periostracum smooth, fairly thin and light- brown. Operculum paucispiral and corneous. Cold-water inhabitants, usually dredged in areas of kelp weed. Figure 36. Northern Lacunas. a, Lacuna carinata Gould, % inch (Pacific coast); b, Lacuna unifasciata Cpr., %4 inch (California); ¢ to e, Lacuna vincta Turton, %% inch (both coasts); ¢, operculum showing reinforcing bar (dotted); d, animal showing the penis on the right side; e, radula (a single row greatly enlarged). Lacuna vincta Turton Common Northern Lacuna Plate 22p; figure 36c-e Arctic Ocean to Rhode Island. Alaska to California. ¥% to % inch in length, 4 to 5 whorls, resembling a Littorina, but charac- terized by its fairly thin, but strong, translucent shell, its shelf-like columella along side of which is a long, narrow, deep umbilical chink. Outer lip fragile. LITTORINIDAE We Shell smooth except for microscopic, spiral scratches. Color light-tan to brown with the spire tinted with purplish rose. Often confused with Litiopa which has a blade-like ridge on the columella just inside the aperture. Com- mon from low water to 25 fathoms. Alias L. divaricata Fab. and solidula Loven. Lacuna unifasciata Carpenter One-banded Lacuna Figure 36b Monterey, California, to Lower California. % inch in length, moderately fragile, similar to the other Lacunas, but characterized by its very narrow, long, chink-like umbilicus and by the carinate periphery of the whorl which bears a fine, dark-brown spiral line. Early whorls usually pinkish, remainder yellowish tan. Umbilicus and colu- mella white. The peripheral carina may be weak or obsolete, and the color line may consist of a series of faint, slanting streaks of light reddish brown. Very common in littoral seaweed and kelp in southern California. Lacuna carinata Gould Carinate Lacuna Figure 36a Alaska to Monterey, California. ¥3 to % inch in length, 3 to 4 whorls, moderately fragile. Aperture semi-lunar, large. Outer lip thin. Columellar chink large, long and white. Shell smooth, chalky-white, but always covered by a thin, yellowish brown, smooth periostracum. Common on kelp weed. L. porrecta Cpr. and striata Gabb are the same. Do not confuse with vincta which has a higher spire and much narrower, brownish-tan umbilical chink. Lacuna variegata Carpenter Variegated Lacuna Puget Sound, Washington, to Santa Monica, California. % inch in length, similar to unifasciata, but having a very deep umbilical chink which is bordered by a sharp ridge. The spiral carina at the level of the suture is very small, but quite sharp. The yellowish tan shell has mot- tlings or oblique bands of darker color. Moderately common in eel-grass along the shore. Family LITTORINIDAE Genus Haloconcha Dall 1886 Haloconcha reflexa Dall Reflexed Haloconch Alaska and the Bering Sea. % inch in length, fragile, 3 whorls; body whorl large. Resembles a Vel- 12 American Seashells utina. Early whorls purplish brown, last whorl translucent, light chestnut- brown. Shell covered by a thin varnish of periostracum of the same color. At the edge of the thin, smooth outer lip, the periostracum is neatly curled back to form a minute ridge. Umbilicus slit-like, with the periostracum puckered along its length. Operculum littorinid, and is withdrawn well within the glossy-brown aperture. Not uncommon in shallow water. Genus Littorina Ferussac 1821 Littorina littorea Linné Common Periwinkle Plate 19b Labrador to New Jersey. Western Europe. % to 1 inch in length, thick, smoothish. Gray to brownish gray in color. Inside of aperture chocolate-brown. Columella and inner edge of aperture whitish. In young or perfect specimens there are fine, irregularly spaced, spiral threads with microscopic, wavy wrinkles in between. Introduced from Europe some time before 1840. A favorite food in Europe. Very common along the rocky shores of New England. Littorina irrorata Say Marsh Periwinkle Plate 19¢ New York to north Florida to Texas. About 1 inch in length, thick-shelled, with numerous, regularly formed spiral grooves. Outer lip strong, sharp, slightly flaring, and with tiny grooves on the inside. Color usually grayish white with tiny, short streaks of reddish brown on the spiral ridges. Aperture yellowish white. Callus of inner lip and the columella pale reddish brown. Commonly found in large numbers among the sedges of brackish water marshes. Not recorded alive south of Indian River (east Florida) or Charlotte Harbor (west Florida). Littorina ziczac Gmelin Zebra Periwinkle Plate 19e South half of Florida to Texas, the West Indies and Bermuda. Females about 1 inch, males about % inch in length. Shell fairly thick and strong. Base angulate; aperture purplish brown. Columella various shades of dark-brown. Outer shell white to bluish white with many narrow, zigzag, Oblique lines of chestnut-brown or purplish brown. Early whorls uniformly pale reddish brown. Female shells: higher than wide, smoothish. Male shells: as high as wide, with strong spiral grooves. Operculum dark- brown. Abundant in crevices between tides in rocky areas. Introduced to the Pacific side of the Panama Canal. Do not confuse with the larger and thinner-shelled L. angulifera whose operculum is light-brown, not dark- brown, in color, LITTORINIDAE 133 Littorina angulifera Lamarck Angulate Periwinkle Plate 19a South half of Florida, the West Indies and Bermuda. About 1 inch in length; thin-shelled but strong. First two or three whorls smooth, remainder with many fine, spiral grooves. Last whorl some- times carinate. Color variable—whitish, yellowish or orange- to red-brown with darker, wavy, vertical, oblique stripes. Columella pale purplish with whitish edges. Operculum pale-brown. Common in mangrove areas where the waters are calm and brackish. It is found high above the high-tide mark clinging to wharf pilings, and is often seen on the trunks and branches of mangrove trees. Introduced to the Pacific side of the Panama Canal. L. scabra Linné is from the Indo-Pacific. Littorina obtusata Linné Northern Yellow Periwinkle Plate rof Labrador to Cape May, New Jersey. Northwest Europe. ¥ to ¥% inch in length, equally wide, with a low spire; smoothish. Color variable but usually a uniform, bright, brownish yellow or orange-yellow. Sometimes with a white or brown spiral band. Columella whitish. Oper- culum bright yellow to orange-brown. This is L. palliata Say. A common coastal species associated with rockweeds. Littorina mespillum Miuhlfeld Dwarf Brown Periwinkle Plate 19k Florida Keys and the Caribbean Area. % inch in length, somewhat shaped like obtusata. Characterized by its dark-brown periostracum, glossy-brown columella and aperture, by its tiny, chink-like umbilicus, and by the presence, in some specimens, of rows of small, round blackish spots. Common in “splash-pools” from high-tide line to 6 or 7 feet above. Littorina saxatilis Olivi Northern Rough Periwinkle Plate 19d Arctic Seas to Cape May, New Jersey. Arctic Seas to Puget Sound. % to % inch in length, resembling a “distorted, small L. Jittorea.” Adults characterized by poorly developed, smoothish, fine spiral cords. Color drab gray to dark-brown. Interior of aperture chocolate-brown. Females give birth to live, shelled young. Often found with L. obtusata, but not so common, This is L. rudis Maton and L. groenlandica Menke. 134 American Seashells Littorina scutulata Gould Checkered Periwinkle Plate 20c Alaska to Lower California. % inch in length, moderately slender, semigloss finish and smooth. Color light to dark reddish brown with small, irregular spots of bluish white. Colu- mella white; interior of aperture whitish brown. A common littoral species. Compare with L. planaxis. Littorina planaxis Philippi Eroded Periwinkle Plate 20a Puget Sound to Lower California. % to %4 inch in length, usually badly eroded; grayish brown with bluish white spots and flecks. Characterized by the eroded, flattened area on the body whorl just beside the columella. Interior of aperture chocolate-brown with a white spiral band at the bottom. A common littoral, rock-loving spe- cies. Do not confuse with the smoother, higher-spired L. scutulata. Littorina sitkana Philippi Sitka Periwinkle Plate zob Bering Sea to Puget Sound, Washington. % inch in length, solid, sharp lip, characterized by about a dozen strong spiral threads on the body whorl. Columella whitish. Shell dark grayish to rusty-brown; some with 2 or 3 wide spiral bands of whitish. A common littoral species of the north. Genus Nodilittorina Martens 1897 Nodilittorina tuberculata Menke Common Prickly-winkle Plate roi South Florida, the West Indies and Bermuda. % to % inch in length. Shell rounded at the base. Several spiral rows of small, fairly sharp nodules on the whorls. Columella flattened, forming a slightly dished-out shelf. Color brownish gray. Operculum paucispiral. A common rock-dwelling species found near the high-tide line. Do not con- fuse with the extremely similar Echininus nodulosus Pfr. which has a multi- spiral operculum, and whose columella is not shelved. Erroneously listed in Johnsonia and other books as Tectarius tuberculatus Wood. Genus Tectarius Valenciennes 1833 Subgenus Cenchritis Martens 1900 Tectarius muricatus Linné Beaded Periwinkle Plate rog Lower Florida Keys, the West Indies and Bermuda. RISSOIDAE 135 % to 1 inch in length. Shell thick, with 11 rows of neat, rounded, whit- ish, evenly spaced beads on the last whorl. Columella grooved; umbilicus a narrow, oblique slit. Color of outer shell ash-gray. Interior dark-tan. Oper- culum paucispiral. One of the commonest West Indian littoral species, usu- ally found well out of water on the rock cliffs. Genus Echininus Clench and Abbott 1942 Subgenus Tectiminus Clench and Abbott 1942 Echininus nodulosus Pfeiffer False Prickly-winkle Plate 19h Southeast Florida and the West Indies. % to 1 inch in length. Base of shell squarish. Whorls with 2 spiral, carinate rows of sharp nodules in addition to 2 or 3 rows of smaller, blunt nodules. Columella not shelved. Color grayish brown. Operculum multi- spiral. Lives well above high-tide mark on rocky shores. Be sure not to confuse with Nodilittorina tuberculata whose beads are lined up axially one under the other. Superfamily RISSOACEA Family RISSOIDAE Genus Cingula Fleming 1828 Extremely small shells, conic-ovate; aperture round, peristome complete; whorls moderately rounded. Nuclear whorls smooth. Umbilicus slit-like. There are about 15 confusing species on the west coast of America, most of which are found in Alaskan waters. Cingula montereyensis Bartsch Monterey Cingula Moss Beach to Monterey, California. 4 mm. in length, light-brown, smooth. Suture slightly indented. Un- common from shore to 15 fathoms. Subgenus Nodulus Monterosato 1878 Cingula kelseyi Bartsch Kelsey’s Cingula San Diego to Lower California. 2 mm. in length, translucent-white, with microscopic spiral striations and fine lines of growth. There are 4 other species in this subgenus which are found in Alaska (C. asser Bartsch, C. Ryskensis Bartsch, C. palmeri Dall and C. cerinella Dall). 136 American Seashells Subgenus Onoba H. and A. Adams 1854 Cingula aculeus Gould Pointed Cingula Nova Scotia to Maryland. Extremely small, 2.5 mm. in length, elongate, about 5 whorls, no um- bilicus. Whorls rounded. Suture well-impressed. Aperture ovate with a slightly flaring lip. Color light- to rusty-brown. Spiral sculpture of numer- ous, microscopic incised lines. Below the suture there are numerous, short, axial riblets. Common in shallow water. Genus Amphithalamus Carpenter 1865 Extremely small shells, less than 2 mm. in length, smooth, except for a faint cord or spiral thread on the periphery. Nucleus large, of 14% whorls which are finely pitted like a thimble. The most striking character is a thin bridge separating the inner lip from the open umbilicus. There are 3 species in southern California: Periphery without spiral line . lacunatus Carpenter (Gan Pecos soutiny: Periphery wich lend or cord: Periphery angulate . . inclusus Carpenter (San Pedro south). Periphery rounded OE ec, a Rtas os. tenuis Bartsch (Monterey south). Genus Rissoina Orbigny 1840 Shells small, usually less than % inch in length, generally white in color, with strong or weak axial ribs, occasionally with fine spiral, incised lines. Aperture semilunar and somewhat flaring. Operculum corneous, thick, pauci- spiral, with a claviform process on the inner surface. We have presented nearly all of the species known to both sides of the United States in the form of a key (see pl, 22u). Key to the Pacific Coast Rissoina A. Color pure-white or bluish white — wt) aes Color yellow to light-red; 6 mm., Redondo Beach south . kelseyi Dall and Rarer B. Axial ribs strong, less than 20 on the last whorl i LG Axial ribs weak, numerous . . Ake, 55) RISSOIDAE lew . Interspaces with silky, wavy crinkles; 3 mm.; Coronado Islands cleo Bartsch Interspaces smooth 3 mm.; Cee rabies. south _ californica Bartsch . Whorls decidedly inflated; 3 mm., eae south. .—sbakeri Bartsch Whorls not inflated Ae on er ee eee rs . With very fine, numerous axial threads (48 to 55 on last whorl) . . F With coarse riblets (36 on last whorl; 14 on next to last); 3 mm. Alaska paMvipmpercye ete Wy Vere eh, cect yi newcombei Dall onelsieniders z mm.-San'Pedro south © .°. . «. '. dally Bartseh Shell not as slender; 3.5 mm.; Redondo Beach south : coronadoensis Bartsch Key to the Atlantic Coast Rissoina . Shell sculptured with riblets or spiral lines me . B Shell smooth, glossy-white; 4 mm.; Carolinas, Blonds, aad West ladies syn.: laevigataC.B. Ads. . . . . . . browniana Orbigny . With axial ribs more prominent than spiralthreads. 2 2 ws C With axial ribs not more prominent than spiral threads . . . . F . Axial ribs only . ee rant eee, ee) Axial ribs and spiral breads bath present j oot ae SAP ee eee . 4.5 to 6.0 mm.; white or stained acs 16 to 22 ribs; South Florida and the West Tndies Lape = _ . . . bryerea Montagu 3-0 to 5.o mm.; white; 11 to 14 ribs: suture sometimes deep; North Caro- lina to Florida aad the West Indies _ Chesneli Michaud (PI. 22u) . 4 to 5 mm.,; ribs strong but disappearing on base; spiral threads strongest on base; white to rusty; southeast Florida and the West Indies multicostata C. B. Adams 6 to 7 mm.; 25 to 28 = Ww eae ribs, spirally striated or pitted between, glossy; white to yellowish; North Carolina to the West Indies decussata Montagu . Sculpture strongly cancellate. G Not strongly cancellate; low, spiral fiteade somisant asial fits fine weakly cancellate; 5 to 10 mm.; southeast Florida and the West fadiests Gs fe). . 4. = sy . . Sioa CBO Adams . 5 to 7 mm.; white; strongly cancellate; depressed interspaces large and square; southeast Florida and the West Indies _ —cancellata Philippi 138 American Seashells 4 to 4.5 mm.; glassy-white; depressed interspaces small, rounded; Texas to the West Indies and Bermuda. . —._—S._—s Sagraiana Orbigny Family VITRINELLIDAE Genus Vitrinella C. B. Adams 1850 Shell minute, thin, depressed, umbilicate, and with 3 to 4 subtubular whorls. The umbilicus has rather flattened walls and is usually bounded by a spiral cord. The rounded aperture is oblique, with a thin lip, its upper margin arching forward. Columella only moderately thickened. Operculum corne- ous, thin, multispiral. There are many species in American waters with quite a number of genera and subgenera. The family is undergoing consid- erable change under the current research by H. A. Pilsbry. We are includ- ing only three examples of this interesting group. Consult recent numbers of The Nautilus. Subgenus Vitrinella s. str. Vitrinella helicoidea C. B. Adams Helix Vitrinella North Carolina to Florida and the West Indies. 2 mm. in diameter, planorboid, 4 whorls, spire moderately raised. Trans- lucent-white, glossy, smooth. Umbilicus round, very deep, moderately wide, bounded by a small, spiral, smoothish thread. Wall of umbilicus flattish. Columella strong, braced on the whorl above by a small, spreading callus. Outer lip thin, sharp. Not uncommon in shallow water. This is the type of the genus. Subgenus Circulus Jeffreys 1865 Vitrinella multistriata Verrill Threaded Vitrinella Plate 17V North Carolina to Florida. 5 mm. in diameter, planorboid, well-compressed, 4 whorls, opaque-white, with a glossy sheen. Outer surface covered with numerous, crowded, spiral, incised lines. Umbilicus with rounded sides, deep, rather narrow. 50 to 100 fathoms. Locally common. Subgenus Solariorbis Conrad 1865 Vitrinella beaui Fischer Beau’s Vitrinella North Carolina to Florida and the West Indies. VITRINELLIDAE 139 ¥ inch in diameter, strong, opaque-white, depressed, 4 whorls. Top of whorls rounded, slightly concave just below the fine suture; bearing 5 or 6 major, smooth, spiral threads on top with numerous, much finer threads be- tween. Periphery bordered above and below by a major cord. Umbilicus widely funnel-shaped, deep. Outer lip crenulate above. Not uncommon in shallow water. One of our largest American Vitrinellid species. Provisionally placed in this subgenus. Genus Pseudomalaxis P. Fischer 1885 Pseudomalaxis nobilis V erril! Noble False Dial Virginia to southeast Florida and the West Indies. 6 inch in diameter, dull-white, planorboid, with a very flat spire and a wide concave, non-umbilicate base. Periphery of shell flat, bordered above and below by one or two spiral cords of small beads. Aperture squarish. Operculum round, multispiral with a chitinous pimple on the inside. A rare and choice collector’s item. Deep water. 70 fathoms. Pseudomalaxis balesi Pilsbry and McGinty Bales’ False Dial Palm Beach and along the Lower Keys, Florida. 1.8 mm. in diameter, 3 to 4 whorls, semitranslucent-white to burnt sienna. Sculpture of fine, spiral striae and strong, widely spaced, radial ribs. Peripheral zone flattened or concave between 2 projecting nodulose keels. Under rocks. Moderately common to rare. This genus was formerly placed in the family Architectonicidae. Genus Teinostoma H. and A. Adams 1854 Shells usually about 2 to 3 mm. in diameter, depressed, glossy, white, usually smooth, and with an umbilical callus. They are very distinctive little shells, but require a high-powered lens for their inspection. We have figured only one species, but have included a key from the work of Pilsbry and McGinty (1945) (see pl. 17y). Key to the Florida Teimostoma 1. Umbilical callus encircled by a keel. 1.7 mm.; Palm Beach to Cape Florida. 12to5ofaths.. © T. (Annulicallus) lituspalmarum Pils. and McG. 2. Umbilical callus and columellar lobe not closing the umbilicus completely; Selkinis- Southeast Moridal: Soshmasia! ile lyy 5.) Let T. (Ellipetylus) cocolitoris Pils. and McG. 140 American Seashells 3. Umbilicus closed by the callus, which passes smoothly into the base. . (subgenus /dioraphe) A. Periphery strongly carinate; 2 mm.; Destin, Florida. 20 fms. gomogyrus Pils. and McG. AA. Periphery ottided or - indistinctly Funded: B. Surface spirally striate: C. Umbilical callus extremely convex and thick; 2 mm. Palm Beach to Cape Florida. . __—pilsbryi McGinty CC. Umbilical callus strong, slightly convex: D. Strongly spirally striate throughout; 2.3 mm.,; Key cargoes _. . ¢lavium Pils. and McG. DD. Weakly striate noone only; 1.5 mm.; southeast Florida hina tae _ nesaeum Pils. and McG. BB. No Spiral striations. C. Diameter 1.8 to 2.2 mm.: D. Rather globose, h/d ratio 75; shore to 50 fms.; south- east Florida. . . —_—Ssparvicallum Pils. and McG. DD. Depressed, h/d ratio about 50: FE. Callus large. Lake Worth . _. obtectum Pile neal McG. EE. Galltis email Biscayne Bay, shore n= oat . biscaynense Pils. and McG. CC. Diameter 0.7 to 1.0 mm.; callus thick; Lower Keys, shore _ leremum Pils. and McG. Superfamily CERITHIACEA Family TURRITELLIDAE Genus Tachyrhynchus Morch 1868 Tachyrbynchus erosum Couthouy Eroded Turret-shell Plate 211 Nova Scotia to Cape Cod, Massachusetts. Alaska to British Columbia. % to 1 inch in length, elongate, %4 as wide; 8 to 10 rounded whorls. No umbilicus. Aperture round; columella smooth, slightly arched. Whorls with 5 to 6 smooth, flat-topped, spiral cords between sutures. Color cream to chalky-white, with a thin, polished, gray-brown periostracum. Operculum round, multispiral, chitinous, dark-brown. Common from ro to 75 fathoms. T. reticulatum Mighels (Arctic Ocean to Maine; and Alaska) is simular, TURRITELLIDAE 141 but usually has spiral cords only on the base and one just above the suture, and has about 18 to ro axial, rounded ribs per whorl. Some specimens show fine, spiral, incised lines. Common from 16 to 60 fathoms. Tachyrhynchus lacteolum Carpenter Milky Turret-shell Alaska to Lower California. % inch in length, similar to erosum, but 4 as wide as long, and the cords between sutures are finely beaded. The beads are arranged more or less in axial rows. The last third of the body whorl bears weak, non-beaded spiral cords. This species differs from reticulatum in its smaller size, less slender shape, less convex whorls, and much finer sculpturing. Genus Turritella Lamarck 1799 Turritella acropora Dall Boring Turret-shell Plate 21] North Carolina to Florida, Texas and the West Indies. 1 inch in length, resembling exoleta, but with convex whorls, and with numerous, fine, spiral threads a few of which, at the periphery, are slightly larger than the others. There is a very weak series of riblets just below the suture. Color yellowish to brownish orange. Common just offshore. T. variegata Linné, the Variegated Turret-shell (pl. 211) (West Indies), is similar, but up to 4 inches in length, with flat-sided whorls, and is mottled with mauve, white and dark-brown. Common. Turritella exoleta Linné Eastern Turret-shell Plate 21h South half of Florida and the West Indies. 2 inches in length, long, slender and with a sharp apex. Each whorl with a large, coarse cord above and below, with the part between the cords con- cave and occasionally crossed by microscopic, arched, brown, scale-like lamellae. Base of shell concave. Color glossy-white to cream with sparse, axial flammules of light yellow-brown. Moderately common from 1 to 100 fathoms. This species is placed in the subgenus Torcula Gray 1847. Turritella cooperi Carpenter Cooper’s Turret-shell Plate 20g Monterey, California, to Lower California. 1 to 2 inches in length, 17 to 20 slightly convex whorls. Base concave. Columella and outer lip fairly fragile. Whorls with 2 or 3 small, spiral cords 142 American Seashells and usually with a number of much smaller, variously sized threads. Color orangish to yellowish white with darker, axial flammules. Moderately com- mon just offshore. Turritella mariana Dall Maria’s Turret-shell Plate 2zoh Catalina Island to Panama Bay, Panama. 1% to 2% inches in length, similar to cooperi, but with the whorls slightly concave due to the more prominent, irregularly beaded spiral cords. The aperture is not circular as in cooperi. Its color is usually much lighter. Uncommon 20 to 4o fathoms. Family ARCHITECTONICIDAE Genus Torinia Gray 1842 Torinia bisulcata Orbigny Orbigny’s Sun-dial Plate 21x North Carolina to Florida and the Gulf of Mexico. Y% to % inch in diameter, spire flattened, each whorl with 5 crowded rows of neat, tiny, squarish beads. Periphery with a major, and below it a minor, beaded cord. Base rounded and with about 7 wide cords bearing beads. Umbilicus quite wide and very deep. Nuclear whorl glassy-white. Color of shell dull gray to dull cream. Operculum solid-conic, chitinous. Uncommon from 15 to 200 fathoms on mud bottom. Torinia cylindrica Gmelin Cylinder Sun-dial Lower Florida Keys and the West Indies. %@ inch in length, equally wide; spire high; umbilicus narrow, round, very deep, bordered inside with 3 spiral, beaded cords. Columella with 4 small, depressed, spiral lines. Top of whorls with 4 spiral cords of closely packed, small beads. Color dark-gray to reddish brown with a cream base and with white spots on the periphery. Uncommon at low tide. Genus Architectonica Roding 1798 Architectonica nobilis Roding Common Sun-dial Plate 4m North Carolina to Florida, Texas and the West Indies. 1 to 2 inches in diameter, heavy, cream with reddish brown spots which are especially prominent just below the suture. Sculpture of 4 or 5 spiral cords which are usually beaded. Umbilicus round, deep and bordered by a VERMETIDAE 143 heavily beaded, spiral cord. Operculum, corneous, thin, paucispiral, brown and with lamellate growth lines. Moderately common in sand below low- water line. Known for years as A. granulata Lamarck which, however, is a later name. Architectonica krebsi Morch Krebs’ Sun-dial Plates 4-0; 21y North Carolina to southeast Florida and the West Indies. % inch in diameter, similar to A. nobilis, but glossy-smooth on top except for two microscopic spiral threads above the suture, with a smooth rounded base and with its deep umbilicus bordered by 2 beaded spiral rows, the innermost having about 30 bar-like beads (in contrast to 12 in nobilis). Operculum chitinous, brown and multispiral. Uncommon from 16 to 63 fathoms. Provisionally placed in this genus. Architectonica peracuta Dall Keeled Sun-dial Plate qn, figure 22g Southeast Florida and the West Indies. %4 inch in diameter, similar to nobilis, but smaller, with the spire much flatter, whorls almost smooth, periphery very sharp, and without color spots. Rare in 45 to 73 fathoms. Family VERMETIDAE Genus Petaloconchus H. C. Lea 1843 Petaloconchus nigricans Dall Black Worm-shell Plate 21e West Coast of Florida. Lives in closely packed colonies of long, worm-like shells about 2 to 4 inches in length; each tube is about % inch in diameter. Shells rarely coiled, except at the beginning. Moderately fragile, gray to rusty-brown in color, and weakly sculptured spirally and longitudinally. Colonies of this species frequently form large reefs or banks. Petaloconchus irregularis Orbigny Irregular Worm-shell Plate 21d South half of Florida and the West Indies. Similar to nigricans, but greatly coiled, and with heavier, larger shells which are strongly rugose. Occurs in compact masses attached to rocks and other shells. Color dark brownish. P. erectus Dall is smoother, pure white in color, and with the last part of the tube sticking straight. up from the 144 American Seashells coiled mass (Erect Worm-shell); the latter occurs in deep water off south- east Florida. Genus Aletes Carpenter 1857 Aletes squamigerus Carpenter Scaled Worm-shell Plate 20e Forrester Island, Alaska, to Peru. Grows in large, twisted masses. The shelly tubes are circular, % to % inch in diameter. Sculpture of numerous, minutely scaled or rough, longi- tudinal cords. Color gray to pinkish gray. The last part of the shell which usually stands erect for % inch is smoothish. A very common, colonial spe- cies found in masses on wharf pilings or attached to rocks below the low- water line. Genus Spiroglyphus Daudin 1800 Spiroglyphus lituellus Morch Flat Worm-shell Plate 20d Forrester Island, Alaska, to San Diego, California. A small worm-tube mollusk found adhering to rocks and the shells of abalones in a tightly wound, flat spiral. The last whorl may grow up on top of the previous whorls and be erect for %4 of an inch. Aperture circular, about ¥% inch in diameter. Shell solid, with 2 large, scaled cords which give a somewhat squarish cross-section to the whole shell. Hollow scales and fimbriations present elsewhere. Color cream to purplish gray. Operculum horny, multispiral and brown. Moderately common. There is a very similar species reported from the West Indies (S. annu- latus Daudin). Family SILIQUARIIDAE Genus Vermicularia Lamarck 1799 Vermicularia spirata Philippi West Indian Worm-shell Plate 2ic; figure 221 Southeast Florida and the West Indies. Evenly and closely spiraled for about %4 inch, then becoming random and drawn out in its worm-like coiling. Shell rather thin, colored a trans- lucent to opaque amber, orange-brown or yellowish. Early whorls dark, smooth, except for 1 (rarely 2) smooth, spiral cord on the middle of the whorl. Subsequent whorls with 2 major cords which soon lose their promi- nence. Smaller threads present, especially on the base of the shell. This is CAECIDAE 145 not the common West Florida species usually called “spirata” in other books. See knorri and also fargoi. For anatomy and relationships in the worm-shells, see the excellent works by J. E. Morton (1951) in the Transactions of the Royal Society of New Zealand. Vermicularia knorri Deshayes Florida Worm-shell Plate 21a North Carolina to Florida and the Gulf of Mexico. Differing from spirata in having the early, evenly coiled part pure white in color. The later whorls are very similar to spirata. Common in sponge masses, and frequently washed ashore. Vermicularia fargoi Olsson Fargo’s Worm-shell Plate 21b West Coast of Florida to Texas. Similar to spirata and knorri, but the “turritella” or wound stage 1s %4 to x inch in length; the shell is thicker and sturdy, its color a drab grayish to yellowish brown. Early whorls tan to brown, with 2 (sometimes 3) spiral cords. Subsequent whorls with 3 major, brown-spotted, thick cords. Aper- ture with a squarish columella corner. Minute minor threads are between the main cords. Commonly found crawling on mud flats. A race occurs in Texas in which the “turritella” stage is much more slender. Genus Tenagodus Guettard 1770 (Siliquaria Bruguiére 1789) Tenagodus squamatus Blainville Slit Worm-shell Plate 21g Southeast Florida and the West Indies. A small worm-like shell with detached whorls throughout. Character- ized by the long row of small holes or elongate slits on the middle of the whorl. Early whorls smooth, white; later whorls becoming very spinose and stained with brown. The coiling is very irregular and loose. Grows to about 5 or 6 inches in length. T. modestus Dall may be the young of this species. Family CAECIDAE These tiny, cucumber-shaped mollusks are occasionally found by screen- ing the beach sand in warm water areas or by shaking out dead sponges. The Caecums begin life in a normal snail-like manner with a tiny, spiral shell, but within a few weeks they grow only in one direction to form a simple, slightly curved tube. The spiral apex is usually knocked off and the hole plugged 146 American Seashells with a septum. As additional growth takes place, the animal retreats grad- ually from the apical or rear portion and forms new, internal septa. The operculum is thin, circular, horny, and multispiral. Figure 37. American Caecums. ATLANTIC: a, Caecum floridanum Stimpson, b, C. cooperi S. Smith; ce, C. carolinianum Dall; d, C. pulchellum Stimpson, e, C. nitidum Stimpson; f, C. nebulosum Rehder (type). PACIFIC: g, C. californicum Dall; h, C. dalli Bartsch (type); i, C. carpenteri Bartsch (type); j, C. occidentale Bartsch (type); k, C. heptagonum Cpr.; 1, C. orcutti Dall (type); m, C. crebricinc- tum Cpr. All Xro. Genus Caecum Fleming 1817 Subgenus Caecum s. str. Caecum floridanum Stimpson Florida Caecum Figure 37a North Carolina to Southern Florida. CAECIDAE 147 3-0 mm. in length by 1.0 mm. in diameter, opaque-white, with 20 to 30 strong, axial rings, the last 3 or 4 being quite large. Caecum cayosense Rehder Key Caecum Bonefish Key, Lower Florida Keys. Shell similar to C. floridanum, but with about 14 very large, sharp axial rings. Caecum californicum Dall California Caecum Figure 37g: Monterey to Lower California. 2.0 to 3.0 mm. in length. With 30 to 40 moderately developed, evenly spaced, rounded or squarish axial rings. Lip of aperture slightly thickened. Color a glossy, olive-brown. Caecum dalli Bartsch Dall’s Caecum Figure 37h San Diego to Lower California. About 3 mm. in length, usually with 18 to 24 moderately developed, evenly spaced, rounded or squarish, axial rings. Lip of aperture usually heav- ily developed in adults. Color tan. The number of raised rings varies from specimen to specimen, often in the same locality, and diligent search will usually bring to light any number desired. Extremes have been unwisely named (15 rings—C. grippi Bartsch; 17 to 19 rings—C. licalum Bartsch, and 19 to 22 rings—C. diegense Bartsch). Figure 37h is the holotype. Subgenus Micranellum Bartsch 1920 Shells 3 to 7 mm. in length, opaque, with numerous, fine, closely packed, axial rings. About 8 Eastern Pacific and perhaps half a dozen Western At- lantic species in this subgenus. Caecum pulchellum Stimpson Beautiful Little Caecum Figure 37d Cape Cod south to North Carolina. About 2 mm. in length, translucent-tan and glistening when alive; chalky-white when dead; with about 25 to 30 fine, closely set axial rings. Apex with a dome-shaped plug. Caecum crebricinctum Carpenter Many-named Caecum Figure 37m Monterey to Lower California. 148 American Seashells 6.0 mm. in length. Color pinkish brown to chalky-white with occa- sional darker brown mottlings. With about 100 fine, squarish, closely set axial rings. Plug with a rather long, oblique spur. Spur sometimes eroded down to a small sharp pimple (form oregonense Bartsch). Irregularities oc- cur in the expansion of the tube; sometimes there is a more rapid expansion toward the anterior end (forms named as species: C. pedroense Bartsch and C. barkleyense Bartsch). C. catalinense Bartsch is probably this species, since many of the paratypes do not have the anterior end supposedly “‘bulbously expanded,” and many specimens have about 100 axial rings, and not 75 as claimed. C. rosanum Bartsch appears to be a very long specimen (7 mm.) with sharply defined rings. Common. Subgenus Elephantanellum Bartsch 3 to 5 mm. in length, white, with axial rings and longitudinal ribs. One species in southern California and 3 or 4 in the Western Atlantic. They resemble minute scaphopods, but are distinguished from them by the apical plug and small size of the shell. Caecum cooperi S. Smith Cooper’s Atlantic Caecum Figure 37b South of Cape Cod to northern Florida. 4 to 5 mm. in length, slender, glossy, opaque-white; with about 15 strong, longitudinal ribs. Axial, raised rings are prominent near the aperture and sometimes give the shell a cancellate appearance at the anterior end. Apical plug with a fairly long, pointed prong. Common. Caecum carpenteri Bartsch Carpenter’s Caecum Figure 371 San Pedro to Lower California. 3-5 to 4.8 mm. in length. First half to first 94 of shell smooth, but at the apertural end developing about a dozen small, sharply defined axial rings. Longitudinal sculpture microscopic or absent. Color translucent-white to gray. This species is doubtfully placed in this subgenus. Caecum heptagonum Carpenter Heptagonal Caecum Figure 37k West Coast of Central America. 2.0 to 2.5 mm. in length. Opaque-white. 7-sided in cross-section. The 7 longitudinal ribs are strong, raised, and the spaces between them are flat or slightly concave. There are about 30 deeply cut circular lines around the CAECIDAE 149 shell, cutting across the ribs. Lip of aperture with one or two swollen axial rings. Subgenus Levia de Folin 1875 Rather thick, glossy, slightly curved shells; aperture minutely con- stricted; sculpture absent except for microscopic growth lines. The shells are larger, heavier and not as bulbous as those in the subgenus Fartulum. Caecum carolinianum Dall Carolina Caecum Figure 37c¢ North Carolina to southern Florida. About 4.5 mm. in length, glossy, cream-white. Smooth except for micro- scopic growth lines. Apical plug sunk in at the posterior end of the shell and with a sharp, horn-like projection. Aperture minutely constricted. Subgenus Fartulum Carpenter 1857 Shells very small, about 2 mm. in length, fragile, smooth, except for microscopic growth lines; not swollen in the middle; and with a noncon- stricted aperture facing to one side (oblique). Caecum nebulosum Rehder Mottled Caecum Figure 37f Missouri Key, Florida Lower Keys. 1.5 to 2.0 mm. in length, fragile, translucent-tan with opaque-white mot- tlings. Not swollen in the center. Aperture oblique. Apex with a lopsided plug which has a single, weak spur. Found under flat rocks imbedded in tough, sticky marl. Caecum orcutti Dall Orcutt’s Caecum Figure 371 San Pedro to Lower California. 2.0 to 2.5 mm. in length. Smooth, except for fine, circular scratches. Shell stubby, slightly compressed laterally; aperture oblique; apical plug dome-shaped. Color translucent-tan to yellow-brown. Moderately common. Caecum occidentale Bartsch Western Caecum Figure 37} Alaska to Lower California. 2.2 to 3.5 mm. in length. Smooth, except for fine, circular scratches. Shell elongate, round in cross-section. Aperture moderately oblique; apical 150 American Seashells plug dome-shaped with a tiny pimple on one side. Color translucent-tan to light-brown. Old specimens are whitish, often with a purplish stain. The shell has a white band behind the aperture. C. bemphilli Bartsch and C. bakeri Bartsch are probably diminutive forms of this species. The development of the small pimple on top of the dome-shaped plug is variable. Subgenus Meioceras Carpenter 1858 Shells 2 to 4 mm. in length, very bulbous in the middle, smooth, and with an oblique, constricted aperture. Resembles a miniature Cadulus (Scaphopoda). Caecum nitidum Stimpson Little Horn Caecum Figure 37e Southern half of Florida and the West Indies. 2.0 mm. in length, glassy translucent-white with irregular specks or mot- tlings of chalk-white; bulbous in the center; apex with a lopsided, rounded plug which has a tiny projection on the highest side. Caecum lermondi Dall from the west coast of Florida differs in having a single, moderately well-raised, circular hump around the middle of the shell. Uncommonly dredged just offshore. Family PLANAXIDAE Genus Planaxis Lamarck 1822 Planaxis lineatus da Costa Dwarf Atlantic Planaxis Lower Florida Keys and the West Indies. % inch in length, thick and strong; glossy-smooth when the thin, smooth- ish, translucent periostracum is worn away. Color whitish cream with neat, spiral bands of brown (10 in last whorl, 5 showing in whorls above). Whorls in top of spire with 4 or 5 small spiral cords, later becoming obsolete. Aper- ture slightly flaring, enamel-white with 10 brown dots on the edge of the outer lip. Nuclear whorls very small, glossy, translucent-brown and sharply pointed. Subgenus Supplanaxis Thiele 1929 Planaxis nucleus Bruguicre Black Atlantic Planaxis Southeast Florida and the West Indies. % inch in length, resembling a thick, polished, dark-brown Littorima periwinkle. Characterized by 5 strong spiral cords which are developed on POTAMIDIDAE ies the outside of the body whorl only in the region behind the slightly flaring lip. 3 other cords are present just below the suture. Columella area dished; reinforced by the round, pillar-like columella. A small pimple is present near the posterior canal in the aperture. Outer lip with strong crenulations on the inside. Periostracum a soft gray-black felt. A common littoral species in the West Indies which bears its young in a brood pouch. Rare in Florida. FicurE 38. Modulus modulus Linné (southeast United States and the West Indies). a, side view of living animal; b, ventral view showing foot, head and under edge of mantle; c, operculum; d, apertural view of shell. X2. (From Abbott 1944 in Jobnsonia.) Family MODULIDAE Genus Modulus Gray 1842 Modulus modulus Linné Atlantic Modulus Plate 21f; figure 38 Florida to Texas and the West Indies. About % inch in length. Characterized by the small, projecting, tooth- like, frequently brownish spine located on the lower end of the columella. Base of shell with about 5 strong, spiral cords. Top of whorls with low, slanting, axial ribs. Color grayish white with beach-worn specimens often exhibiting flecks of purple-brown. Found abundantly among weeds in shal- low, warm waters. Modulus carchedonius Lamarck, the Angled Modulus (Caribbean area) lives in deeper water, and differs in having the periphery of the shell well- angulated, the spiral cords smaller and neater, in lacking the strong, axial ribs, and in never having the columella tooth colored. Not too common. Family POTAMIDIDAE Subfamily POTAMIDINAE (Horn Shells) Genus Cerithidea Swainson 1840 152 American Seashells The horn shells are intertidal mud-lovers. The shells are elongate and with ro to 15 convex whorls. Axial ribs are more prominent on the early whorls. Outer lip flares. Operculum horny, thin, paucispiral and with its nucleus at the center. Subgenus Cerithideopsis Thiele 1929 Cerithidea costata da Costa Costate Horn Shell : Plate rou West coast of Florida and the West Indies. ¥% inch in length, translucent, pale yellowish brown. With 9 to 12 very convex whorls. Axial, curved ribs are round and distinct on the early whorls, fading out on the last two whorls. No old varices present. A common shallow-water, mud-loving species. The subspecies C. costata turrita Stearns, the Turret Horn Shell from the Tampa-Sanibel region, has 15 to 20 (instead of 25 to 30) axial ribs on the next to the last whorl. Cerithidea pliculosa Menke Plicate Horn Shell Plate rot Texas, Louisiana and the West Indies. Not Florida. 1 inch in length, brownish black in color. 11 to 13 slightly convex whorls. Several yellowish, former varices are present. Numerous spiral threads make the axial ribs slightly nodulose. Locally common. It may yet turn up in northwest Florida. Cerithidea scalariformis Say Ladder Horn Shell Plate 19x South Carolina to south half of Florida and the West Indies. %4 to 1% inches in length. Pale russet-brown to slightly violaceous, usu- ally with many conspicuous, dirty-white, spiral bands. 10 to 13 moderately convex whorls. Many coarse, axial ribs present which stop abruptly below the periphery of the whorl at a sharply marked, rounded spiral ridge. Base of shell with 6 to 8 spiral ridges. No former varices. Common on mud flats. Cerithidea hegewischi californica Haldeman California Horn Shell Bolinas Bay, California, to Lower California. 1 to 1% inches in length, resembling our photo of C. pliculosa from the Atlantic (pl. r9t). Whorls 11, spirally and weakly threaded, and axially strongly ribbed (12 to 18 ribs per whorl). Dark-brown in color with 1 or GERITHIIDAE 153 2 yellowish white, swollen varices on the spire. A very common species found in large colonies on mud flats. Cerithidea Batillaria Cerithium RTA Figure 39. Last whorl and opercula in the Horn Shells. (From J. Bequaert in Jobnsonia.) Subfamily BATILLARIINAE Genus Batillaria Benson 1842 Cerithium-like in appearance. Siphonal canal very short and twisted to the left. Outer lip smooth inside. Operculum round, multispiral and horny, while in Cerithidea and Cerithium it is paucispiral. Batillaria minima Gmelin False Cerith Plate 19s South half of Florida and the West Indies. ¥% to %4 inch in length, resembling the Dwarf Cerith, C. variabile (see below). Color varies from black, gray to whitish, and often has black or white spiral lines. Finely nodulose with coarse axial swellings and uneven spiral threads. The siphonal canal is very short and twisted slightly to the left. Operculum multispiral. A very common intertidal species. Percy Morris (1951, pl. 31, fig. 15) labels this species as Cerithidea turrita, Family CERITHIIDAE Genus Cerithium Bruguicre 1789 Thericium Monterosato is this genus. The operculum is horny, thin, brown and paucispiral. Most species in the genus are shallow-water dwellers. Cerithium floridanum Morch Florida Cerith Plate 19n North Carolina to the south half of Florida. 1 to 1% inches in length, elongate. Spire pointed, with 2 or 3 white, former varices on each whorl. Siphonal canal well-developed. With several spiral rows of 18 to 20 neat beads per whorl between which are fine, granu- lated spiral threads. Color whitish with mottlings and specklings of reddish brown. Distinguished from C. literatum by its more elongate shape and neater, smaller, more numerous beads. Common in shallow water. 154 American Seashells Cerithium muscarum Say Fly-specked Cerith Plate 19m South half of Florida and the West Indies. 1 inch in length, moderately elongate. Siphonal canal rather long and twisted to the left. 9 to 11 nodulated axial ribs on each whorl. Base of shell with a very strong spiral cord, often nodulated. Former varices rarely pres- ent. Apertural side of body whorl convex. Color slate- to brown-gray, usually with brown to reddish specks in spiral rows. Common in shallow, warm waters on the west coast of Florida. Cerithium literatum Born Stocky Cerith ; Plate rol Southeast Florida, Bermuda and the West Indies. 1 inch in length, half as wide; siphonal canal short. Aperture side of body whorl slightly flattened. Usually 1 weak, former varix present. With numerous Coarse spiral threads, and with a spiral row of 9 to 12 sharp, promi- nent nodules just below the suture. Sometimes a second, smaller row of spines is on the periphery. Color whitish with spiral rows of many black or reddish squares. Common in shallow water on the Lower Florida Keys. Cerithium eburneum Bruguicre Ivory Cerith Plate 19q Southeast Florida, the Bahamas and Greater Antilles. %4 to 1 (rarely 144) inches in length, variable in shape, but usually moderately elongate. Each whorl has 4 to 6 spiral rows of from 18 to 22 small rounded beads. The beads are slightly larger in the middle row. There are usually a number of fairly large, former varices. Color variable: all white or cream, or with reddish brown blotches. Very common in shallow water. C. versicolor C. B. Adams is this species. Compare with algicola which may ultimately prove to be a genetic form of this species. Cerithium algicola C. B. Adams Middle-spined Cerith Plate r9p Southern third of Florida and the West Indies. 1 inch in length, similar to eburneum, but characterized by each whorl having the middle spiral row of 9 to 12 beads fairly large and pointed. These large beads may be axially drawn out to form low ribs. Former varices are not often present. Color as in eburneum. Common in the West Indies. C. literatum has its strongest row of spine-like beads just below the suture. Cerithium variabile C. B. Adams Dwarf Cerith Plate 19-0 South half of Florida to Texas and the West Indies. CERITHILDAE 1}5)) % to % inch in length, not elongate. Apertural side of body whorl sometimes flat. 1 to 2 former varices on last whorl. 3 or 4 spiral rows of even-sized fine beads on the whorls of the spire. Color dark brown-black, but sometimes whitish with heavy specklings and mottlings and bands of reddish brown. Very common under rocks in warm water. Do not confuse with Batillaria minima (see above). Genus Bittium Gray 1847 Shell small, very slender, spire high and body whorl small. Whorls varicose. Nucleus of about 3 glassy, smooth whorls. Aperture ovate, the anterior canal broad and stout. Subgenus Bittium s. str. Bittium alternatum Say Alternate Bittium Gulf of St. Lawrence to Virginia. Adults very small, % to 4 inch in length, light- to dark-brown in color, sometimes translucent or with specklings. Suture impressed, whorls rounded. Sculpture on top whorls either cancellate or with 4 to 5 spiral rows of beads, or occasionally with axial, nodulated ribs. Base with small spiral cords. Outer lip flaring, thin and sharp. Columella short, twisted at the base and stained brown. Very abundant from tidal flats to 20 fathoms. B. virginicum Henderson and Bartsch from Chincoteague, Virginia, is similar, but very elongate, more whorls, with a much more flaring and basally projecting lip, and with a large, whitish, former varix on the body whorl. Bittium varium Pfeiffer Variable Bittium Plate 19r Maryland to Florida, Texas and Mexico. Adults similar to alternatum, but smaller (% inch), nearly always with a former, thickened varix. The aperture is proportionately smaller and the base of the apertural lip is squarish instead of rounded. The last third of the body whorl is generally destitute of sculpturing. Common in eel-grass just below low tide. Subgenus Stylidium Dall 1907 Bittium eschrichti Middendorf Giant Pacific Coast Bittium Alaska to Crescent City, California. 156 American Seashells % to % inch in length, dirty whitish gray in color with an undertone of reddish brown. About a dozen whorls. With wide, flat-topped, raised spiral cords between which are depressed, squarish, spiral furrows half as wide as the cords. 4 to 5 cords between sutures. Common below low water. The subspecies ontereyense Bartsch (Crescent City south to Lower California) is glossy, whitish with brown maculations and is proportionately shorter, Bittium quadrifilatum Carpenter Four-threaded Bittium Monterey, California, to Lower California. % inch in length, similar to attenuatum, but earliest whorls with about a dozen smooth axial ribs which, however, in subsequent whorls become beaded as 4 to 5 small spiral threads cross them. The sculpturing may become faint at the very last third of the last whorl. Color reddish brown to gray. A very common littoral species, Bittiwm attenuatum Carpenter Slender Bittium Forrester Island, Alaska, to Lower California. %, inch in length, slender, yellowish brown to dark-brown. Sculpture variable. Nuclear whorls with two smooth spiral cords. Early whorls have 4 to 5 spiral rows of small beads, sometimes arranged axially. In the last whorl, the cords gradually become smooth and flat-topped and resemble those of eschrichti, Common just offshore to 35 fathoms. Subgenus Lirobittium Bartsch 1911 Bittium interfossum Carpenter White Cancellate Bitttum Monterey, California, to Lower California. ¥% inch in length, pure-white; whorls in spire with 2 rows of sharp beads connected by small axial and spiral threads or small cords. Base of shell with 3 very strong, rounded, smooth spiral cords. Moderately common under rocks at low tide. Subfamily LITIOPINAE Genus Litiopa Rang 1829 Litiopa melanostoma Rang Brown Sargassum Snail Plate 21k Pelagic in floating sargassum weed. —. Se eee — — —-——— EEE ee CERITHIIDAE 157 %6 to % inch in length, fragile, light-brown; moderately elongate, with 7 whorls, the last being quite large. Nuclear whorls extremely small. Sur- face glossy, smooth, except for numerous, microscopic, incised spiral lines. Characterized by the strong ridge just inside the aperture on the columella. Often washed ashore with floating sargassum weed, and frequently dredged in a dead condition at any depth. This is L. bombix Kiener and L. bombyx “Rang.” Subfamily CERITHIOPSINAE Genus Cerithiopsis Forbes and Hanley 1849 Cerithiopsis greeni C. B. Adams Green’s Miniature Cerith Plate rov Cape Cod to both sides of Florida. % inch in length, elongate, slightly fusiform in shape, glossy-brown in color. g whorls, the first 3 embryonic, translucent-brown and smooth, the remainder with 2 to 3 spiral rows of large, glassy beads connected by weak spiral and axial threads. Columella arched in young specimens, but straight and continuous with the short siphonal canal in adults. Lip in adults smoothish, slightly flaring. C. virginica Henderson and Bartsch and C. van- byningi Bartsch are possibly variations of this species. Common in shallow water. Subgenus Laskeya Iredale 1918 Cerithiopsis subulata Montagu Awl Miniature Cerith Plate 19w Massachusetts to the West Indies. ¥% to %4 inch in length, rather strong, slender and with about 14 whorls. Sides of whorls flattish, with 3 rows of distinct, raised, roundish beads (about 28 per row on the last whorl). There may be faint axial riblets connecting the beads. The middle row of beads may be reduced to a mere thread in specimens from southern localities. Base concave and with fine axial growth lines. Color chocolate-brown, with the beads a lighter shade. Some shells become eroded and colored an ash-gray or chalky-brown. C. emersoni C. B. Adams is probably a synonym. Common from 1 to 33 fathoms. Cerithiopsis carpenteri Bartsch Carpenter’s Miniature Cerith Crescent City, California, to Ensenada, Mexico. % to ¥% inch in length, dark chocolate-brown with whitish beads. Whorls in spire with 3 spiral rows of evenly sized, glassy, rounded beads. 158 American Seashells Base of shell with 2 large, smoothish, spiral cords. C. grippi Bartsch and C. pedroana Bartsch are possibly dwarf forms of this species whose beaded sculpture is more variable than is generally suspected. Genus Seila A. Adams 1861 Shell small, very slender, whorls flat-sided, nucleus glassy-smooth and of about 3 whorls. Small, short siphonal canal. Sculpture of strong spiral cords between which lie microscopic axial threads. Seila adamsi H. C. Lea Adams’ Miniature Cerith Plate 22t Massachusetts to Florida, Texas and the West Indies. % to % inch in length, resembling a miniature Terebra, with about a dozen whorls. Long, slender, flat-sided, dark-brown to light orange-brown in color, and characterized by 3 strong, squarish, spiral cords on each whorl (4 on the last whorl). Occasionally with minute axial threads showing be- tween the spiral cords. Base of shell smoothish, concave. Outer lip fragile, wavy and sharp. Suture indistinct. This is S. terebralis C. B. Adams. Common from shore to 4o fathoms. Seila montereyensis Bartsch Monterey Miniature Cerith Monterey, California, to the Gulf of California. ¥8 to % inch in length, yellowish to reddish brown. Whorls and spire flat-sided. Whorls in spire with 3 raised, flat-topped, evenly spaced, smooth cords between which are numerous, microscopic, axial threads. Last whorl with 5 cords. Base smoothish, concave. Common from low tide to 35 fathoms. Genus Alabina Dall 1902 Shell small, slender. Nucleus slender, of 3 to 4 glassy, smooth whorls. Aperture subcircular. Lower part of the outer lip extended and flaring. Umbilicus very narrow and very small. With obscure, narrow, curved axial ribs and prominent spiral threads. This genus is put in the family Diastomidae by some workers. Alabina tenuisculpta Carpenter Sculptured Alabine San Pedro, California, to Lower California. % inch in length, slender, 8 to 9 whorls, ashen gray with a light-brown undertone. Outer lip thin; umbilicus small. Spiral sculpture of 4 to 6 weak TRIPHORIDAE 159 cords or threads. Axial sculpture of weak, obsolete or sometimes strong, very tiny, rounded riblets. A. t. diegensis Bartsch is a strongly sculptured form of this species. Family TRIPHORIDAE Genus Triphora Blainville 1828 Shell left-handed (sinistral), very small, and slender. Aperture subcir- cular. Siphonal canal short, curved backward, slightly emarginate, upper part almost or completely closed. Posterior canal very slightly developed. Sculpture of spiral rows of neat beads, often joined by axial threads. Triphora nigrocincta C. B. Adams Black-lined Trifora Plate 19y Massachusetts to Florida, Texas and the West Indies. ¥% to %4 inch in length, left-handed, with ro to 12 slightly convex whorls; dark chestnut-brown with 3 spiral rows of prominent, grayish, glossy beads. Darker band of black-brown is just below the suture. Aperture and columella brown. A common species found on seaweed at low tide. Some- times considered a subspecies of perversa from Europe. Triphora decorata C. B. Adams Mottled Trifora Plate 19zz Southeast Florida, the West Indies and Bermuda. % inch in length, left-handed, with about 20 flat-sided whorls which bear 3 spiral rows of large beads (28 per row per whorl). Color of shell cream to gray with large, irregular maculations of reddish brown. Moderately common from 1 to 4o fathoms. T. ornata Deshayes from the same area 1s very similar, but half as large, the spire slightly concave instead of being flat. Triphora pulchella C. B. Adams Beautiful Trifora Plate 19z Southeast Florida and the West Indies. 346 inch in length, left-handed, spire slightly convex; 15 whorls slightly convex, and with 3 spiral rows of beads which are joined axially and spirally by small, low, smooth threads. Suture well-indented. Upper third of whorl, including beads, colored light-brown, lower two thirds white. Uncommon in shallow water down to 56 fathoms. Triphora pedroana Bartsch San Pedro Trifora Redondo Beach, California, to Lower California. 160 American Seashells % inch or less in length, slightly fusiform with very slightly convex sides to the spire. Suture almost impossible to see. Color glossy yellow-brown with 2 rows of glassy, whitish, rounded beads. A third much weaker row of beads, or an additional spiral thread, may appear in the last 2 or 3 whorls. Axial threads connecting the beads are weak and form small pits. Fairly common under stones along the low-tide zone. Family JANTHINIDAE Genus Janthina Roding 1798 Subgenus Janthina s. str. Janthina janthina Linné Common Purple Sea-snail Plate 4j Pelagic in warm waters; both coasts of the United States. 1 to 1% inches in diameter. Whorls slightly angular. Two-toned, with purplish white above and deep purplish violet below. Outer lip very slightly sinuate. Common after certain easterly blows along the south- eastern United States, especially from April to May. This is J. fragilis Lamarck. Subgenus Violetta Iredale 1929 Janthina globosa Swainson Globe Purple Sea-snail Plate 4k Cast ashore along both coasts of the United States. % to % inch in diameter. Whorls globose, well-rounded. Color violet throughout. Outer lip very slightly sinuate. Not very common. Subgenus Jodima Morch 1860 Janthina exigua Lamarck Dwarf Purple Sea-snail Plate 4l Cast ashore in most warm seas. % inch in length. Whorls slightly flattened from above. Outer lip with a prominent notch. Light-violet, banded at the suture. Fairly common. J. bifida Nuttall is probably this species. NOTE Superfamily PY RAMIDELLACEA The families Pyramidellidae, Aclididae, Eulimidae, Styliferidae and Entoconchidae, most of which are small parasitic gastropods, have in the past been placed here among the prosobranchs, but are now considered to EPITONIIDAE 161 be opisthobranchs and related to the bubble shells. Recent work on the embryology and anatomy appears to justify this radical change in classifica- tion, They are located in this book on page 288. Superfamily EPITONIACEA Family EPITONIIDAE (Wentletraps) Genus Sthenorytis Conrad 1862 Sthenorytis pernobilis Fischer and Bernardi Noble Wentletrap Figure 4oc North Carolina to southeast Florida and to Barbados. 1 to 1% inches in length, solid, pure-white to grayish, angle of spire about 50 degrees. The 10 whorls are globose and each bears about 14 very large, thin, blade-like ribs. Apertural rim round, solid. A very choice col- lector’s item. It is the only member of the genus in Western Atlantic waters, S. cubana Bartsch, S. hendersoni Bartsch and S. epae Bartsch being minor forms of this rare species. Figure 40. Atlantic Wentletraps. a, Cirsotrema dalli Rehder, 1% inches; b, Amaea mitchelli Dall, 2 inches (Texas); ce, Sthenorytis pernobilis Fischer and Bernardi, 1 inch; d, Amaea retifera Dall, 1 inch; e, Epitonium krebsi Morch, 34 inch. 74 Genus Cirsotrema Morch 1852 Cirsotrema dalli Rehder 7 Dall’s Wentletrap Plate 22c; figure goa North Carolina to southeast Florida and to Brazil. 162 American Seashells 1 to 1% inches in length, rather slender, with a quite deep suture, thus giving the whorls a shouldered appearance. No umbilicus. Color a uniform, chalky grayish white. Outer lip with a thickened varix. Whorls with numer- ous groups of foliated costae. Surface pitted with small holes when the costae or ribs are closely crowded. Uncommon from 18 to 75 fathoms. C. arcella Rehder is believed to be the young of this species. Genus Acirsa Morch 1857 Acirsa costulata Mighels and Adams Costate Wentletrap Arctic Ocean to Massachusetts. %4 to 174 inches in length, rather turreted in shape and fairly thin in structure. 8 to 9 moderately convex whorls are devoid of sculpture except for weak, incised spiral lines and, in the early whorls, numerous but incon- spicuous costae. Color straw to whitish, rarely with brown lines. Uncom- mon from low water to 50 fathoms. This is Scalaria borealis Beck. Genus Opalia H. and A. Adams 1853 Subgenus Dentiscala de Boury 1886 Opalia hotessieriana Orbigny Hotessier’s Wentletrap Plate 22g Southeast Florida and the Caribbean. ¥ to % inch in length, moderately slender. Characterized by 10 to 14 large, square notches along the suture of each whorl. Ribs are rather weak. Surface, in fresh specimens, microscopically pitted. Color grayish white. Not uncommon from low water to 90 fathoms. O. crenata Linné (same range, but also the Eastern Atlantic) is larger, its whorls more strongly shouldered, and the notches at the suture are much weaker and more nu- merous. Opalia wroblewskii Morch Wroblewski’s Wentletrap Plate 20] Forrester Island, Alaska, to off San Diego. 1 to 1% inches in length, slender, heavy; looks beachworn; grayish white in color, often stained purple from the animal’s dye gland. With 6 to 8 low, pronounced, axial, wide ribs. Base of shell bounded by a strong, smooth, low, spiral cord. Fairly common. O. chacei (Chace’s Wentletrap) is probably a southern representative of this species. Opalia insculpta Carpenter Scallop-edged Wentletrap Southern California to west Mexico. EPITONIIDAE 163 % to % inch in length, dull whitish, 7 to 8 whorls, moderately slender. Characterized by the smoothish sides of the whorls and by the spiral ramp below the suture which bears 12 to 14 short, horizontal ribs per whorl. Early whorls may have weak axial ribs running from suture to suture. Spinal sculpture of microscopic, numerous scratches. O. crenimarginata Dall is this species. Very common among rocks at low tide. Genus Amaea H. and A. Adams 1854 Amaea mitchelli Dall Mitchell’s Wentletrap Plate 22f; figure 4ob Texas coast to Yucatan. 1% to 2% inches in length, thin but strong; without an umbilicus. With about 15 rather strongly convex, pale-ivory whorls which have a dark brown- ish band at the periphery and a solid brown area below the basal ridge. About 22 low, irregular costae per whorl. Numerous spiral threads are fine, and produce a weak, reticulated pattern. Not very common, but occasionally washed up on Texas beaches. Subgenus Scalina Conrad 1865 (Ferminoscala Dall 1908) Amaea retifera Dall Reticulate Wentletrap Figure 4od North Carolina to both sides of Florida to Barbados. 1 inch in length, elongate, thin but strong; with about 16 whorls which are beautifully reticulated by strong, sharp threads. Color straw to pale- brown with 2 light and narrow brownish bands, one above and one below the periphery. Commonly dredged off Florida from 13 to 120 fathoms. Genus Epitonium Roding 1798 (Scala) Subgenus Epitonium s. str. Epitonium krebsi Morch Krebs’ Wentletrap Figure 4oe South half of Florida to the Lesser Antilles. ¥% to %4 inch in length, stout. With umbilicus fairly narrow to wide, and very deep. 7 to 8 whorls attached by the costae (10 to 12 per whorl). China-white, rarely with a trace of brown to pinkish brown undertones. Moderately common from a few feet to 160 fathoms. E. swifti Morch and E. contorquata Dall are this species. Do not confuse with E. occidentale Nyst (Western Atlantic Wentletrap) from the same areas. It is not so stout, has 12 to 15 costae per whorl, a very 164 American Seashells small umbilicus or none, and the shoulder of the whorls is somewhat flattened. It is not common. Epitonium tollini Bartsch Tollin’s Wentletrap West Coast of Florida. ¥% inch in length, slender, no umbilicus. 9 to 10 whorls strongly convex; suture deep. Each whorl has from 11 to 16 costae which are not shouldered, but are rounded, on top. They often line up one below the other. Outer lip thick and reflected. Inner lip much smaller. Color china-white, with the first few whorls a very faint amber-brown. Fairly common just off the outer beaches. Do not confuse with E. humphreysi whose costae are angular at the top. Epitonium humphreysi Kiener Humphrey’s Wentletrap Plate 22d Cape Cod, Massachusetts, to Florida and to Texas. % to %4 inch in length, fairly slender, thick-shelled, and without an umbilicus. Color dull-white. Suture deep. The 9 to 10 convex whorls each have about 8 to 9 costae that are somewhat angled at the shoulder. Costae usually thick and strong. Outer and lower part of the apertural lip thickened and slightly flaring. Common from shore to 52 fathoms. Do not confuse with E. angulatum which is not so slender, is glossier, has thinner costae that are usually more angular at the shoulders. Epitonium eburneum Potiez and Michaud listed by Percy Morris (1951, p. 122) does not occur in American waters. His illustrations are probably those of E, commune Linné from Europe. Epitonium angulatum Say Angulate Wentletrap Plate 22b New York to Florida and to Texas. %4 to 1 inch in length, moderately stout to somewhat slender, strong and without an umbilicus. 8 whorls with about 9 to ro strong but thin costae which are very slightly reflected backwards and which are usually angu- lated at the shoulder, especially in the early whorls. The costae are usually formed in line with those on the whorl above and are fused at their points of contact. Outer lip thickened and reflected. Color china-white. One of the commonest Atlantic wentletraps found in shallow water to 25 fathoms. Do not confuse with E. humphbreysi. Epitonium foliaceicostum Orbigny Wrinkled-ribbed Wentletrap Southeast Florida to the Lesser Antilles. HIPPONICIDAE 165 ¥% to % inch in length, moderately stout, without an umbilicus, and similar to E. angulatum, except that the 7 to 8 costae per whorl are thinner, more highly developed and usually quite angular. Moderately common from low water to 120 fathoms. Alias muricata Sby., spina-rosae Morch and pre- tiosula Morch. Subgenus Gyroscala Boury 1887 Epitonium lamellosum Lamarck Lamellose Wentletrap Plates 22a South half of Florida and the Caribbean. Also Europe. $4 to 1% inches in length, without an umbilicus. 11 whorls whitish with irregular, brownish markings. Costae thin, high, always white. Characterized by a fairly strong, raised, spiral thread on the base of the shell. Moderately common from low water to 33 fathoms. Alias E. clathrum of authors, not Linné. Epitonium rupicola Kurtz Brown-banded Wentletrap Plate 22e Cape Cod, Massachusetts, to Florida and to Texas. ¥% to 1 inch in length, moderately stout to slender, and without an um- bilicus. Color whitish or yellowish with 2 brownish, spiral bands on each side of the suture. Color often diffused. About 11 globose whorls, each of which has from 12 to 18 weak or strong costae. Former, thickened varices sometimes present. Base of shell with a single, fine, spiral thread. Formerly known as lineatum Say and reynoldsi Sby. Common from low water to about 20 fathoms. Epitonium indianorum Carpenter Money Wentletrap Forrester Island, Alaska, to Lower California. 1 inch in length, slender, pure white, of 11 whorls, each of which has 13 to 14 sharp costae which are slightly bent backwards. The tops of the costae are slightly pointed. Fairly common offshore. Superfamily HIPPONICACEA Family HIPPONICIDAE Genus Cheilea Modeer 1793 Cheilea equestris Linné False Cup-and-saucer Plate 21p Southeast Florida and the West Indies. 166 American Seashells % to 1 inch in size, cap-shaped, dull-white, and with an internal, delicate, deep cup which has its anterior third neatly sliced away. The base of the cup is attached near the center of the inside of the shell but slightly off in the direction in which the apex of the shell points. Exterior has small, axial corrugations or tiny cords, rarely spinose. Nucleus minute, spiral and glassy- white. Uncommon except in the West Indies. Genus Hipponix Defrance 1819 Hipponix antiquatus Linné White Hoof-shell Plate 21t Southeast Florida and the West Indies. Crescent City, California, to Peru. % inch in size, white, heavy for its size, cap-shaped, and usually with a poorly developed spire which may be located either at one end of the shell or near the center. The nuclear whorls are spiral and glassy-white. There is a horseshoe-shaped muscle scar inside the shell. Axial sculpture of promi- nent, rugose ribs which are crossed by microscopic, incised lines. Periostracum absent or very thin and light-yellowish. Moderately common. Found cling- ing to rocks and other shells. Some Pacific northwest specimens are limpet-like in shape, flattish, cir- cular, gray-white, with the apex near the center of the shell, and with smooth- ish, strong, circular cords (form cranoides Carpenter). Another form bears foliaceous concentric lamellae which are finely striate axially (serratus Car- penter from Monterey to Panama). Hipponix subrufus subrufus Lamarck Orange Hoof-shell Southeast Florida and the West Indies. 2 inch in size, similar to antiquatus, but usually stained with light orange- brown, and with numerous, small spiral cords crossing concentric ridges of about the same size. This frequently gives a beaded surface. Periostracum fairly heavy, tufted and light brown. Moderately common. Hipponix benthophilus Dall (Dall’s Deepsea Hoof-shell) is well-spired in one plane and is entirely smooth. It is rare and comes from deep water off Florida and throughout the West Indies. Hipponix subrufus tumens Carpenter Pacific Orange Hoof-shell Crescent City, California, to Lower California. Very close in characters to the Atlantic subrufus subrufus, but the shell TRICHOTROPIDAE 167 is white in color (although the periostracum is yellow-brown), with more prominent spiral threads, and with coarser spiral threads in the young. Found offshore. Hipponix barbatus Sowerby (Bearded Hoof-shell) from the same region is limpet-shaped, with coarse, nodulated ribs which are largest on the anterior slope of the shell. The edge of the shell is strongly serrated with cut lines. The periostracum is very shaggy especially on the middle of the anterior slope. Common. Family VANIKOROIDAE Genus Vanikoro Quoy and Gaimard 1832 Vanikoro oxychone Morch West Indian Vanikoro Southeast Florida and the West Indies. ¥, inch in length, solid, strong and pure white. With 3 whorls. Charac- terized by its large aperture, by its deep, narrow, arched umbilicus and straight, rounded, pillar-like columella and by the 10 or 12 beaded, spiral cords on the last whorl. Small axial threads tend to give a slightly cancellate sculpture. Apex glassy and smooth. Suture well-indented. Uncommon in shallow water. Superfamily CALYPTRAEACEA Family TRICHOTROPIDAE Genus Trichotropis Broderip and Sby. 1829 Trichotropis borealis Broderip and Sowerby Boreal Hairy-shell Plate 24d Arctic Seas to Maine. Arctic Seas to British Columbia. ¥% to %4 inch in length, with 4 to 5 carinate whorls. Shell not very strong, chally-white and covered with a thick, brownish periostracum which has hairy spicules on the region of the shell’s 3 major spiral cords. Umbilicus chink-like, bordered by a large, spiral cord. Spire usually eroded badly. Numerous, crowded axial threads present. A common cold-water species found from below low water to go fathoms. Trichotropis cancellata Hinds Cancellate Hairy-shell Plate 24b Bering Sea to Oregon. 4 to 1 inch in length, 5 to 6 rounded whorls bearing between sutures 4 to 5 strong spiral cords, between which there may be small axial ribs which produce a cancellate sculpturing. Spire high, rather pointed. Aperture a little 168 American Seashells more than % the length of the shell. Periostracum thick, brown and with long spicules over the region of the cords. Commonly dredged in cold, shallow water. Trichotropis bicarinata Sowerby Two-keeled Hairy-shell Plate 24a Arctic Ocean to Alaska. Arctic Ocean to Newfoundland. 1% inches in length, equally wide, with about 4 whorls. Characterized by 2 strong, spiral carinae at the periphery, by the wide, flattened columella and by the flaky, brown periostracum which is grossly spinose on the carinae. Uncommon just offshore in cold water. Trichotropis insignis Middendorft Gray Hairy-shell Plate 24c Alaska to northern Japan. 1 inch in length, similar to T. bicarinata but smaller, with a much heavier shell, weakly carinate with other numerous, uneven, spiral threads, and with a thin, grayish periostracum. Both this species and bicarinata are easily distin- guished from the more common cancellata by their much shorter spires and large flaring apertures. Uncommon just offshore. Family CAPULIDAE Genus Capulus Montfort 1810 Subgenus Krebsia Morch 1877 Capulus incurvatus Gmelin Incurved Cap-shell North Carolina to southeast Florida and the West Indies. % inch in size, cap-shaped, white to cream, and with a very large, cir- cular to slightly oval aperture. 1/4 to 2 whorls. Spire small, usually tightly coiled, but sometimes partially free. Early whorls usually with small spiral cords, but these are frequently worn smooth. Sculpture of small, irregular, rounded growth lines which are crossed by numerous spiral cords which may be rounded or sharp. Periostracum thick, light-brown, with spirally ar- ranged rows of small tufts. Muscle scar within the aperture is horseshoe- shaped with the swollen end just inside the columella. Uncommon on rocks just below low water. I believe that C. mtortus Lamarck is merely a variant of this species. Compare with Hipponix antiquata which is much heavier, lacks the spiral cords and is more coarsely sculptured. Capulus californicus Dall Californian Cap-shell Redondo Beach to Lower California. CALVETRAEIDAE 169 1% inches in diameter, 4% as high, obliquely ovate, fairly thin, and with a small, hooked-over apex. Shell white, covered by a soft, fuzzy, light-brown periostracum. Interior glossy-white. A rather rare species found in 20 to 30 fathoms attached to Pecten diegensis. Family CALYPTRAEIDAE Genus Calyptraea Lamarck 1799 Calyptraea centralis Conrad Circular Cup-and-saucer Plate 21-0 North Carolina to Texas and the West Indies. % to % inch in diameter, cap-shaped, with a circular base, and pure white in color. Apex central, small, minutely coiled and glossy-white. The shelly cup is attached to the inside of the shell and is flattish, arises near the center of the shell and flares out to the edge. Its free side is thickened into a columella-like, rounded edge. Commonly dredged in shallow water, espe- cially off southeast Florida. Formerly known as C. candeana Orbigny. Calyptraea fastigiata Gould Pacific Chinese Hat Plate 201 Alaska to southern California. 1% to 1 inch in diameter, about % to % as high; the outline of the base of the shell is perfectly circular, and the apex is at the center of the shell. Interior glossy-white with the sinuate edge of the internal cup arising at the apex of the shell as a thickened, twisted columella and ending in fragile at- tachment near the edge of the shell. Young forms (C. contorta Cpr.) are relatively higher-spired. Exterior chalky-white with a thin, brownish perios- tracum. Dredged moderately commonly from 10 to 75 fathoms. Genus Crucibulum Schumacher 1817 Crucibulum auricula Gmelin West Indian Cup-and-saucer Plate 21s West Florida to the Lower Keys and West Indies. 1 inch in diameter, similar to C. striatum, but the edges of the inner cup are entirely free. The edges of the main shell are crenulated, the external ribs are coarser, and the interior is sometimes pinkish. The outer surface may show coarse diagonal ribs if the specimen has lived attached to a scallop or other ribbed mollusk. Uncommonly dredged in shallow water and occasion- ally washed ashore. 170 American Seashells Crucibulum spinosum Sowerby Spiny Cup-and-saucer Figure 71 Southern California to Chili. %4 to 1 inch in diameter, variable in height (7% to %4 as high), and usually with an almost circular base. Exterior with a smoothish apical area, the re- mainder of the shell with radial rows of small prickles or sometimes erect, tubular spines. Interior glossy, chestnut-brown, sometimes with light radial rays, and with a delicate white cup attached by one side. A very common species from low water to 15 fathoms. Albino shells are sometimes found. Subgenus Dispotaea Say 1826 Crucibulum striatum Say Striate Cup-and-saucer Plate 21r Nova Scotia to South Carolina (and Florida? ). 1 inch in diameter, cap-shaped, base round, edge smoothish and the slightly twisted apex near the center of the shell. Interior of shell with a small, shelly cup, of which only % is free from attachment to the main shell. Apex wax color and smooth; remainder of exterior with small, wavy, radial cords. Interior glossy, yellow-white or tinted with light orange-brown. Commonly dredged in shallow water. Genus Crepipatella Lesson 1830 Crepipatella lingulata Gould Pacific Half-slipper Shell Plate 20k Bering Sea to Panama. % to %4 inch in diameter, thin, almost circular, low and with the apex near the edge of the shell. Characterized by its tannish to mauve-white, glossy interior which has a shallow deck which is attached to the main part of the shell only along one side. The middle of the deck often has a weakly raised ridge. Exterior wrinkled and brownish. A very common species found on rocks and on the shells of living gastropods. Genus Crepidula Lamarck 1799 Crepidula fornicata Linné Common Atlantic Slipper-shell Plate 21m Canada to Florida and to Texas. 34 to 2 inches in size. Shelly deck extending over the posterior half on the inside of the shell. The deck is usually concave and white to buff. Its edge is strongly sinuate or waved in two places. Exterior dirty-white to tan, sometimes with brownish blotches and rarely with long color lines. . | | ] CALVPT RAEIDAE Leal Variable in shape, rarely quite flat, sometimes high and arched. They may be corrugated if the individual has lived attached to a scallop or ribbed mussel. A common littoral species. When collecting on the west coast of Florida, do not confuse with C. maculosa. C. fornicata has been introduced to the West Coast of the United States. Crepidula maculosa Conrad Spotted Slipper-shell West Coast of Florida to Vera Cruz, Mexico. Resembling C. fornicata, but often spotted with small, mauve-brown blotches and sometimes streaked. The edge of the deck is straight or only very slightly convex. There is an oval muscle scar on the inside of the shell just below and in front of the right anterior edge of the deck and the main shell. The young are very much like southern forms of C. convexa Say. Crepidula convexa Say Convex Slipper-shell Plate 21n Massachusetts to Florida, Texas and the West Indies. % to % inch in size, usually highly arched and colored a dark reddish to purplish brown. Interior, including the deck, chestnut to bluish brown. Some specimens may be spotted. The edge of the deck is almost straight. There is a small muscle scar inside the main shell on the right side just under the outer corner of the deck (see also maculosa). Some specimens are thick and heavy, others quite fragile, the latter type found attached to other shells. Common just offshore down to 116 fathoms. The form glauca Say is 4 inch long, thin-shelled, usually dark-brown or translucent-tan, and with a white deck. It is found in over-crowded col- onies on eel-grass where specimens become long and narrow. C. acuta Lea is this form also. Crepidula aculeata Gmelin Spiny Slipper-shell Plate 21q North Carolina to Florida, Texas and the West Indies. % to 1 inch in size, similar to formicata, but characterized by its rough, spinose exterior, thinner and flatter shell and by its irregular edges. Color whitish, although often heavily mottled with reddish brown. The exterior is sometimes stained green by algal growths. A common species found at- tached to stones, mangroves and other shells. Occasionally dredged. Crepidula onyx Sowerby Onyx Slipper-shell Plate 20f Monterey, California, to Peru. 172 American Seashells 1 to 2 inches in length, fairly thick-shelled, characterized by its glossy, dark-chocolate to whitish brown interior, and by the large, slightly concave, pure-white deck inside which has a sinuate free edge. Very common from shallow estuaries to 50 fathoms on rocks, on other shells, or stacked up on top of each other. Crepidula excavata Broderip Excavated Slipper-shell Monterey, California, to Peru. 1 inch in size, rather thin; back strongly arched with the apex distinct and hooked under itself near the posterior margin of the shell. Characterized by its light brownish white color, by the straight or slightly curved edge of the interior deck, and by a weak muscle scar on each side just under the deck. Found commonly attached to rocks and other shells. Subgenus Janacus Morch 1852 Crepidula plana Say Eastern White Slipper-shell Canada to Florida and the Gulf States. Rare in the West Indies. % to 17% inches in size, very flat, either convex or concave, and always a pure milky white. The apex is very rarely turned to one side. It commonly attaches itself to the inside of large, dead shells, and rarely, if ever, “piles up” like fornicata. A common shallow-water species. Crepidula nummaria Gould Western White Slipper-shell Alaska to Panama. % to 1% inches in length, characterized by its glossy-white underside, flattened shell, large deck which usually has a weak, raised ridge (or some- times a hint of an indentation) running from the apical end forward to the leading edge. Exterior with or without a yellowish periostracum. Found in rock crevices and apertures of dead shells. Superfamily STROMBACEA Family XENOPHORIDAE Genus Xenophora Fischer von W. 1807 This group of gastropods is noted for its peculiar habit of cementing to its own shell fragments of other shells, stones, bits of coral and coal. The animals resemble those of the Strombus conchs, but the operculum is much wider and not sickle-shaped. B. R. Bales once humorously observed: STROMBIDAE hes “It is generally admitted that the camouflage of Xenophora is for protection rather than ornamentation, for it would be inconceivable that a female Xenophora would call over the back fence to her girl friend with, ‘Come and see the perfect dream of a shell I picked up today and tell me if I have it on straight.’ ”’ There are 3 species in the Atlantic, one a shallow water species, the other two (longleyi Bartsch, pl. 23d, and caribaea Petit, pl. 23e) deep water inhabit- ants. Xenophora conchyliophora Born Atlantic Carrier-shell Plate sb North Carolina to Key West and the West Indies. 2 inches in diameter, not including foreign attachments. No umbilicus. From above, the shell with its attached rubble and shells looks like a small heap of marine trash. It will attach any kind of shell to itself, but in some areas has access to only one kind, say Chione cancellata. Animal bright-red. Seasonally not uncommon. Johnsonia is in error in calling this trochiformis Born 1778 (not 1780), which is the Peruvian shell known formerly as Trochita radians Lam. Family APORRHAIDAE Genus Aporrhais da Costa 1778 Aporrhais occidentalis Beck American Pelican’s Foot Plate 23c Labrador to off North Carolina. 2 to 2% inches in length, spire high, whorls well-rounded and with about 15 to 25 curved axial ribs per whorl. Many minute spiral threads present. Outer lip greatly expanded and its edge heavily thickened. Color ashen-gray to yellowish white. Operculum small, corneous, brown, claw-like, but with smooth edges. Commonly dredged off New England from a few to 200 fathoms. : The form mainensis C. W. Johnson (Nova Scotia to Mt. Desert) differs in having 14 axial ribs, instead of about 22 to 25 as in the typical form, but specimens intergrade. The form Jabradorensis C. W. Johnson is smaller, more slender, and with up to 29 ribs per whorl. Family STROMBIDAE Genus Strombus Linné 1758 Strombus pugilis Linné West Indian Fighting Conch Plate 5g Southeast Florida and the West Indies. 174 American Seashells 3 to 4 inches in length. Always with spines on the last whorl, but those on the next to the last whorl are nearly always the largest. Shoulder of outer lip nearly always turns slightly upwards. Color a rich cream-orange to salmon-pink throughout, except for a cobalt-blue splotch of color on the end of the canal. Periostracum very thin and velvety. This is primarily a West Indian species, and apparently will not interbreed with the mainland species, S. alatus. An aberrant form which has club-like spines was unneces- sarily named sloani Leach 1814 and peculiaris M. Smith 1940. Percy Morris’ colored figure (1951, pl. 19, fig. 9) 1s not pugilis, but alatus. Strombus alatus Gmelin Florida Fighting Conch Plate sh South Carolina to both sides of Florida and to Texas. 3 to 4 inches in length. With or without short spines on the shoulder of the last whorl. Shoulder of outer lip slopes slightly downward. Color a dark reddish brown, often mottled with orange-brown or having zigzag bars of color on the shiny parietal wall. Periostracum very thin and velvety. A very common shallow water species, especially on the west coast of Florida. Not found in the West Indies. Do not confuse with S. pugilis. Strombus gigas Linné Queen Conch Plate 23a Southeast Florida and the West Indies. Bermuda. 6 to 12 inches in length. Characterized by its large size, large and flaring outer lip, and the rich pinks, yellows and orange shades in the aperture. Peri- ostracum fairly thick and horny. It flakes off in dried specimens. A malform with flattened spines was named horridus M. Smith. A form with a deep chan- nel at the suture occasionally turns up in the Bahamas. It was named canali- culatus L. Burry. S. gigas verrilli McGinty is a form of questionable value described from Lake Worth, Florida. Very common in the West Indies, becoming uncommon in the Florida Keys from over-fishing. Also called the Pink Conch. Strombus costatus Gmelin Milk Conch Plate 23b Southeast Florida and the West Indies. 4 to 7 inches in length. Shell very heavy usually, and with low, blunt spines. Parietal wall and thick outer lip highly glazed with cream-white enamel. Outer shell a yellowish white. The periostracum in dried specimens flakes off. Common in the West Indies. S. spectabilis A. H. Verrill is this species. LAMELLARIIDAE 175 Strombus raninus Gmelin Hawk-wing Conch Plate 5c ‘Southeast Florida and the West Indies. 2 to 4 inches in length. Shell bluntly spinose with the last two spines on the last whorl by far the largest. Outer lip points upward at the top. Color of outer shell a brownish gray with chocolate-brown mottlings. Aper- ture cream-colored with a salmon-pink interior. Common in the West Indies. S. bituberculatus Lamarck is the same species. Strombus gallus Linne Rooster-tail Conch Plate se Southeast Florida (rare) and the West Indies. 4 to 6 inches in length, characterized by the long extension of the poste- rior end of the outer lip and the rather high spire. This species is not at all common, although it may be obtained in fair numbers along the north coast of Jamaica. Superfamily CYPRAEACEA Family LAMELLARIIDAE Genus Lamellaria Montagu 1815 Lamellaria diegoensis Dall San Diego Lamellaria Figure 43d Southern California. ¥% inch in length, equally wide, quite fragile and transparent-white in color. 3 whorls moderately globose, the last large. Aperture very large. Columella very thin. Surface smoothish, except for fine, irregular growth lines. Periostracum thin, clear and glossy. Uncommon offshore. Lamellaria rhombica Dall (Washington to Lower California) is the same size, much flatter and thicker-shelled, and is opaque-white in color. Its colu- mella is thicker and ridge-like. This species is more common than the pre- ceding and is commonly washed ashore. Subfamily VELUTININAE Genus Velutina Fleming 1821 Velutina laevigata Linné Smooth Velutina Plate 22n Labrador to Cape Cod, Massachusetts. Alaska to Monterey, California. % to % inch in length, very thin and fragile, translucent amber, and covered with a thick, brownish periostracum which is spirally ridged. Colu- mella arched and narrow. Common offshore from 3 to 50 fathoms. V. undata 176 American Seashells Brown (zonata Gould is the same) from the Gulf of St. Lawrence to Cape Cod is similar, but rarely over 43 inch in length, with a flattened shelf-like columella, and often colored with narrow, spiral bands of brown. Family FOSSARIDAE Genus Fossarus Philippi 1841 Fossarus elegans Verrill and Smith Elegant Fossarus Plate 25c Massachusetts to North Carolina. 2 to 3 mm. in length, turbinate in shape, with 4 whorls, chalky-white to gray in color and characterized by its delicate sculpturing which consists of 2 strong carinae on the periphery and 3 smaller ones below and a large one bordering the chink-like umbilicus. Between the cords are numerous, distinct, arched riblets. Outer lip thickened by a large varix. 2 or 3 smaller, former varices commonly present on the last whorl. The base of the arched columella is projecting. Uncommon below 70 fathoms. Family ERATOIDAE Subfamily ERATOINAE Genus Erato Risso 1826 Subgenus Hespererato Schilder 1932 Erato maugeriae Gray Mauger’s Erato Plate 22w North Carolina to Florida and the West Indies. “%6 inch in length, resembling a small Marginella, but the curled-in, thickened outer lip has a row of about 15 small, even-sized teeth. Upper end of the outer lip is well-shouldered. Shell glossy, tan with a pinkish or yellow- ish undertone. Apex bulbous. Commonly dredged on either side of Florida from 2 to 63 fathoms. Erato columbella Menke Columbelle Erato Monterey, California, to Panama. % inch in length, glossy-smooth, slate-gray in color with a whitish, thickened outer lip. Spire elevated, nucleus brown. Outer lip markedly shouldered above, and bearing about a dozen extremely small teeth. Siphonal canal stained inside with purple-brown. Not uncommon from shore to 50 fathoms. Occasionally washed ashore with kelp weed. Erato vitellina Hinds Apple Seed Plate 20-0 Bodega Bay, California, to Lower California. ERATOIDAE 177 ’ ¥, inch in length, resembling a “beach-worn Columbella,” and glossy- smooth. Body whorl with a large purple area bounded by a faint whitish line; remainder of shell, including the spire which is often glazed over, is dark brownish cream. Columella arched, bearing 5 to 8 small, whitish teeth. Lower % of slightly incurled outer lip is with 7 to 1o small, whitish teeth. Moderately common in fairly shallow water. Occasionally washed ashore with kelp weed. Subfamily TRIVIINAE Genus Trivia Broderip 1837 Resembling miniature cowries (Cypraea), but characterized by strong wrinkles or riblets running around the shell from the slit-like aperture to the center of the back of the shell. We have carefully reviewed and included all of the Western Atlantic species, but have not followed the Schilderian use of numerous genera, such as Pusula Jousseaume. Trivia pediculus Linné Coffee Bean Trivia Plate 21bb South half of Florida and the West Indies. ¥, inch in length, characterized by its tan to brownish pink color with 3 pairs of large, irregular, dark-brown spots on the back, and in having 16 to 19 (usually 17) ribs crossing the outer lip. The center pair of spots on the back are the largest. Some specimens may be quite pink. In some areas, a dwarf form of this species occurs (named pullata Sby.) which is %4 inch in length, with a pink base, 13 to 17 riblets on the outer lip, and often with the brown mottlings spread over most of the back. Do not confuse this form with the species szffusa which is light-pink, with a white (not pink) outer lip crossed by 19 to 24 riblets, and with a pink blotch on each side of the anterior canal. T. pediculus is a common species found from low water to 25 fathoms. Trivia suffusa Gray Suffuse Trivia Plate 21aa Southeast Florida and the West Indies. % to ¥% inch in length, elongate-globular, bright-pink with suffused brownish splotches and fine specklings. Anterior canal with a weak pinkish blotch on each side. Riblets on back somewhat beaded. Dorsal groove fairly well-impressed. Outer lip white and crossed by 18 to 23 (usually 20) riblets. Quite common in the Bahamas and Lesser Antilles. T. armandina Kiener is the same. 178 American Seashells Trivia maltbiana Schwengel and McGinty Maltbie’s Trivia Plate 21z North Carolina to Florida and the Caribbean. % to ¥% inch in length, globose, slightly flattened above, and character- ized by its pale tannish pink, translucent color, by its fine riblets, and by having 24 to 28 ribs crossing the outer lip. Areas between the ribs are micro- scopically granular. Nuclear whorls visible through the last whorl. The dor- sal groove is slight and the riblets nearly cross it. Moderately common just offshore to 50 fathoms. Trivia quadripunctata Gray Four-spotted Trivia Southeast Florida, Yucatan and the West Indies. ¥s to % inch in length, very similar to swzffusa, but smaller, brighter pink, and with 2 to 4 very small, dark red-brown dots on the center line of the back. Ruiblets very fine, 19 to 24 crossing the outer lip. A very common species frequently found on beaches with the color dots worn away and the pink background rather faded. The riblets on the back are never pustulose as they tend to be in szffusa, nor is there any fine color speckling. Trivia antillarum Schilder Antillean Trivia Southeast Florida and the Antilles. % to % inch in length, characterized by its deep reddish or brownish purple color. Elongate-globular in shape. Riblets smooth. With or without a faint dorsal groove over which the riblets usually cross. Outer lip with 18 to 22 teeth. Dredged from 30 to 100 fathoms and rarely cast upon the beach. Formerly T. swbrostrata Gray. Trivia candidula Gaskoin Little White Trivia Plate 21cc North Carolina to southeast Florida to Barbados. % to % inch in length, characterized by its fairly globular shape, pure- white color, somewhat rostrate ends and by the smooth riblets that pass over the back. There is no dorsal furrow. Many specimens have only a few rather strong riblets of which 17 cross the inside of the outer lip. Another common form has more riblets (20 to 24 over the outer lip). It has been named Jeucosphaera Schilder (globosa of authors, not Gray). The forms intergrade. Trivia nix is also white, but is larger, more globose and with a strong dorsal groove interrupting the ribs. ERATOIDAE 179 Trivia nix Schilder White Globe Trivia Southeast Florida and the West Indies. 3g inch in length, globular, pure-white in color. Characterized by about 22 to 26 riblets. Back with a strong groove interrupting the riblets. Alias T. nivea Gray. This is the largest and most globular of the white species found in the Western Atlantic, It is moderately uncommon. Trivia ritteri Raymond Ritter’s Trivia Monterey, California, to Lower California. 6 inch in length, globular, pure-white in color. Characterized by about 15 fine riblets that run over the bottom, sides and back of the shell without being interrupted by a dorsal groove. Uncommonly dredged on gravel bot- tom from 25 to 60 fathoms. Trivia californiana Gray Californian Trivia Plate 20v California to Lower California. ¥, to just less than % inch in length, rotund, and characterized by its mauve color, white, slightly depressed crease on the midline of the back, and by the fairly coarse riblets crossing over the entire shell (outer lip with about 15). A common littoral species, often washed ashore with seaweed. Also lives as deep as 40 fathoms. Trivia sanguinea Sowerby, a more south- erly species, is larger, deeper purple, without the prominent white streak on the back and with finer, more numerous riblets (outer lip with about 20). Trivia solandri Sowerby Solander’s Trivia Plate 20u Catalina Island to Panama. ¥e to %4 inch in length, rotund, and characterized by the strong, raised, smooth riblets running over the lip and up onto the back. Dorsal groove deep, cream-colored and flanked by 8 to 10 cream nodules on each side. Ground color of shell dark purplish brown. Moderately common in the lit- toral zone. Trivia radians Lamarck (Lower California to Ecuador) is larger, flatter, and witli a brownish spot on the back which discolors the central groove. It is fairly common. 180 American Seashells Family CYPRAEIDAE Genus Cypraea Linné 1758 Subgenus Trona Jousseaume 1884 Cypraea zebra Linné Measled Cowrie Plate 6d Southeast Florida and the West Indies. 2 to 3% inches in length, oblong, light-faun to light-brown, with large, round, white dots over the back. Toward the base of the shell these white dots have a brown center. The shell is darker brown, narrower and less inflated than cervus. Moderately common in intertidal waters. Formerly called C. exanthema Linne. A light orangish form, probably due to being buried in sand for some time, was described from Cuba (form vallei Jaume and Borro 1946). Cypraea cervus Linneé Atlantic Deer Cowrie Plate 6f Southern half of Florida and Cuba. 3 to 5 inches in length, similar to zebra, but usually with smaller and more numerous white spots, with a more inflated and larger shell, and never has ocellated spots on the base of the shell. Moderately common from low tide to several fathoms. Subgenus Luria Jousseaume 1884 Cypraea cinerea Gmelin Atlantic Gray Cowrie Plate 6c Southeast Florida and the West Indies. %4 to 1% inches in length, rotund, with its back brownish mauve to light orange-brown which may be flecked with tiny, black-brown specks. Base cream to old ivory with light mauve-brown between some of the teeth, or sometimes with tiny flyspecks of brown. A moderately common species found under rocks on reefs. Subgenus Erosaria Troschel 1863 Cypraea spurca acicularis Gmelin Atlantic Yellow Cowrie Plate 6a South half of Florida, Yucatan and the West Indies. ¥ to 1% inches in length; back irregularly flecked and spotted with orange-brown and whitish. Base and teeth ivory-white. Lateral extremities often with small pie-crust indentations. Distinguished from cinerea in being flatter and without color on the base. A moderately common species found under rocks at low tide. True spurca L. is from the Mediterranean. GVERAEI DAE 181 Cypraea mus Linné (pl. 6e) is often found in American collections al- though it is limited to the southern part of the Caribbean. It is 2 inches in length, mouse-gray (Mouse Cowrie), and has a pair of irregular black-brown stripes on the back. It is frequently deformed with one or two small bumps on the back. Subgenus Zonaria Jousseaume 1884 Cypraea spadicea Swainson Chestnut Cowrie Plate 6b Monterey, California, to Cerros Island, Lower California. 1 to 2 inches in length, half as high, with a hard, glossy enamel finish. Base white, with about 20 to 23 teeth on each side of the long, narrow aper- ture. Sides bluish to mauve-gray, above which there is dark-chocolate fading on top to light chestnut-brown with a bluish undertone. Moderately com- mon at certain seasons at low tide among seaweed, and also down to 25 fathoms. Family OVULIDAE Genus Primovula Thiele 1925 Subgenus Pseudosimnia Schilder 1927 Primovula carnea Poiret Dwarf Red Ovula Plate 22q Southeast Florida, the West Indies and the Mediterranean. % to % inch in length. This species resembles a miniature cowrie. The body whorl is rotund, pink to yellow in color and with numerous, fine spiral, incised lines. Aperture narrow, arched, and with a canal at each end. Outer lip curled in like that of a cowrie, and with about 20 small, rounded, whitish teeth. Upper parietal wall with a large, rounded, short ridge or tooth. Apex not showing. Rare from 25 to 100 fathoms. Genus Pedicularia Swainson 1840 Subgenus Pediculariella Thiele 1925 Pedicularia decussata Gould Decussate Pedicularia Plate 7d Georgia to southeast Florida and the West Indies. ¥% to ¥% inch in length, moderately thick-shelled, with a long and flaring aperture, and pure-white in color. Sculpture of fine reticulations with the spiral threads the strongest. Columella a straight ridge with the parietal wall concavely dished. The entire shell has a distorted, “squeezed” appearance. Nuclear whorls obese, translucent-brown, reticulated, and with a sinuate lip 182 American Seashells when in its free-swimming, larval stage. An uncommon species found cling- ing to coral stems in moderately deep water. This is the only Eastern Ameri- can species in this genus. Pedicularia californica Newcomb Californian Pedicularia Plate’ 7b;.c Farallon Islands to San Diego, California. ¥e to % inch in length, solid, aperture greatly enlarged and flaring. Apex hidden by the expanded lip. Early whorls showing minute decussations, the rest of the shell with small spiral threads. Interior uneven and glossy. Color rose with the outer lip whitish. Uncommon. Found attached to red hydro- coralline, Allopora californica Verrill. We have also illustrated the form ovuliformis Berry (pl. 7c). Genus Neosimnia Fischer 1884 Neosimnia acicularis Lamarck Common West Indian Simnia Plate 7a North Carolina to southeast Florida and the West Indies. % inch in length, narrow, glossy, thin-shelled but strong, and with a long, toothless aperture. Color deep lavender or yellowish. Columella area flattened or sometimes slightly dished and, in adults, always bordered by a long, whitish ridge, one inside the aperture, the other on the body whorl. Posterior end of columella sometimes slightly swollen. A common species which attaches itself and its tiny egg-capsules to purple or yellow seafans. Neosimnia uniplicata Sowerby Single-toothed Simnia Plate 7e Virginia to both sides of Florida and the West Indies. ¥% to %4 inch in length, similar to acicularis, but with only the innermost, longitudinal ridge on the columella, and with a twisted, spiral plication at the posterior end of the columella. Moderately common on seafans. Neosimnia piragua Dall Dall’s Treasured Simnia Plate 7f Between Jamaica and Haiti. 1 inch in length, extremely narrow, with the ends greatly produced. Columella area bordered by two longitudinal ridges, the inner one tinted with rose. Remainder of shell yellowish white. One of the rarest of the Western Atlantic mollusks. 23 fathoms. OVULIDAE 183 Neosimnia avena Sowerby Western Chubby Simnia q i Plate 7g Monterey, California, to Panama. % inch in length, oblong, with short extremities. Lower end of the aperture wide, upper end narrow where the columella has a spiral swelling. Inner and lower part of the columella with a long, light-colored ridge. Exte- rior of whorls with numerous, microscopic, wavy, incised scratches. Color mauve to deep-rose with the varix and extremities a lighter pink. Rare in California, uncommon southward. S, similis Sowerby is probably this species. Neosimnia loebbeckeana Weinkauft Loebbeck’s Simnia Plate 7i Monterey, California, to the Gulf of California. % inch in length, translucent yellowish, rather fragile, and fusiform in shape with the extremities narrow and the middle gently swollen. Columella rounded, usually smoothish, but sometimes with a hint of flattening and sub- sequent thickening of the lower part of the columella. Upper end of the columella with a weak, spiral fold. two subspecies have been described (barbarensis Dall and catalinensis Berry) but their distinctiveness has not been clearly demonstrated as yet. Not uncommonly dredged in association with seafans from 20 to 50 fathoms, Neosimnia inflexa Sowerby Inflexed Simnia Plate 7h Monterey, California, to Panama. % inch in length, a very vivid and dark lavender-rose or reddish purple. Shell elongate; columella flattened, bordered within and also somewhat on the body whorl by a long, axial, lighter-colored ridge. N. variabilis Carpenter is this species, and detailed studies of the animals may also show that N. aequalis Sowerby 1s a synonym. Genus Cyphoma Roding 1798 Cyphoma gibbosum Linné Flamingo Tongue Plates 8; 4r North Carolina to southeast Florida and the West Indies. %4 to 1 inch in length, glossy-smooth, chubby, and colored a rich cream- orange to apricot-buff except for a small whitish rectangle on the back. Callus on sides of shell indistinct and extending high up on the back with poorly defined edges. Mantle of animal pale-flesh with numerous squarish, black rings. Fairly common on gorgonians below low water. 184 American Seashells Cyphoma mcgintyi Pilsbry McGinty’s Cyphoma Plates 8; 4s Lower Florida Keys and the Bahamas. Similar to gibbosa, but more elongate, whitish with tints of lilac or pink on the back. The side callus on the right is thick and narrow. Aperture cameo-pink. Mantle with numerous solid spots which are roughly round or in the shape of short bars, Not uncommon. Cyphoma signatum Pilsbry and McGinty Fingerprint Cyphoma Plate 4t Lower Florida Keys. Similar to mcgintyi, but with the transverse ridge on the back much weaker, and the anterior end of the aperture more dilated than in the two preceding species. Color light-buff with a cream-buff tint deep inside the aperture. Mantle pale-yellow with numerous, crowded, long, black trans- verse lines, The rarest of the Florida Cyphomas. Superfamily HETEROPODA Family ATLANTIDAE Genus Atlanta Lesueur 1817 Atlanta peroni Lesueur Peron’s Atlanta Figure 41 Atlantic and Pacific warm waters; pelagic. ¥% inch in diameter, planorboid, compressed from above, fragile, trans- parent and glassy. Later whorls cpenly coiled but connected by a sharp peripheral keel. Outer lip notched in the region of the shell. Often washed ashore after storms, and frequently brought up in dredge hauls. Five other species have been reported from American waters. £ERWSW DNS \ \ * B/S Se AY ; LZ NX Wnt ge 169: Pp: q. u. W. wa bb. ce FALSE CUP-AND-SAUCER, Cheilea equestris L., % inch (Florida Keys and West Indies), p. 165. SPINY SLIPPER-SHELL, Crepidula acu- leata Gmelin, 34 inch (North Carolina to; texas; south), pyle STRIATE CUP-AND-SAUCER, Crucibu- lum striatum Say, 1 inch (Nova Scotia to South Carolina), p. 170. WEST INDIAN CUP-AND-SAUCER, Cru- cibulum auricula Gmelin, 1 inch (West Florida, south), p. 169. WHITE HOOF-SHELL, Hipponix anii- quatus L., 4% inch (Florida, south; Cali- fornia, south), p. 166. GRACEFUL MELANELLA, Melanella gracilis C. B. Ads., 4% inch (North Ca- rolina to Gulf of Mexico), not in text. FAT MELANELLA, Melanella gibba De Folin, 4% inch (North Carolina to Gulf of Mexico), not in text. TWO-LINED MELANELLA, Melanella bilineata Alder, 14 inch (North Carolina to West Indies), not in text. ORBIGNY’S SUN-DIAL, Torinia bisulcata Orb., 1/3 inch (North Carolina to Gulf of Mexico), p. 142. KREBS’ SUN-DIAL, Architectonica krebsi Morch, 4% inch (North Carolina to West Indies), p. 143. MALTBIE’S TRIVIA, Trivia maltbiana Schw. and McG., 14 inch (North Caro- lina to Florida, south), p. 178. . SUFFUSE TRIVIA, Trivia suffusa Gary, '/s inch (Southeastern Florida and West Indies); p. 177. COFFEE BEAN TRIVIA, Trivia pediculus L., 4 inch (Florida to Brazil), p. 177. LITTLE WHITE TRIVIA, Trivia candi- dula Gaskoin, 4% inch (North Carolina to West Indies), p. 178. gee - aa igen 2. e —* d. sje) m. Prank 22 ATLANTIC GOAST UNIVALVES LAMELLOSE WENTLETRAP, Epitonium lamellosum Lam., 1 inch (Florida and Caribbean), p. 165. ANGULATE WENTLETRAP, Epitonium angulatum Say, 1 inch (New York to diexas) yr. H64: DALL’S WENTLETRAP, Circostrema dalli Rehder, 1 inch (North Carolina to Brazil), p. 161. HUMPHREYS WENTLETRAP, nium humphreysi Wiener, %%4 (Massachusetts to Texas), p. 164. BROWN-BANDED WENTLETRAP, Epzi- tonium rupicola Kurtz, 1 inch (Mas- sachusetts to Texas), p. 165. MITCHELL’S WENTLETRAP, Amaea mitchelli Dall, 2 inches (Texas), p. 163. HOTESSIER’S WENTLETRAP, Opalia hotessieriana Orb., % inch (South- eastern Florida, south), p. 162. SHARK EYE, Polinices duplicatus Say, 2 inches (high-spired form) (Massachusetts to Texas), p. 186. MILK MOON-SHELL, Polinices lacteus Guilding, 1 inch (North Carolina to West Indies), p. 185. SOUTHERN MINIATURE NATICA, Natica pusilla Say, 1/3 inch (Mass2- chusetts to Gulf and West Indies), Pp: Lo: GREENLAND MOON-SHELL, JLunatia gronlandica Moller, 1 inch (Arctic to off New Jersey), p. 189. CAROLINA MOON-SHELL, Sigatica caro- linensis Dall, % inch (North Carolina to West Indies), p. 187. SPOTTED NORTHERN MOON-SHELL, Lunatia triseriata Say, 4% inch (Canada to off North Carolina), p. 189. Epito- inch p- q- Uu. SMOOTH VELUTINA, Velutina laevigata L., % inch (Arctic to Massachusetts; also to California), p. 175. LIVID NATICA, WNatica livida Pfr. 4% inch (Southeastern Florida and West Indies), p. 191. COMMON NORTHERN LACUNA, La- cuna vincta Turton, ¥% inch (Arctic to Rhode Island; also to California), p30: DWARF RED OVULA, Primovula carnea Poiret, 14 inch (Southeastern Florida and West Indies), p. 181. ICELAND MOON-SHELL, islandica Gmelin, 1 inch Massachusetts), p. 187. COMMON BABY’S EAR, Sinum perspec- tivum Say, 114 inches (Virginia to ‘Texas, south), p. 190. Amauro psis (Arctic to ADAM’S MINIATURE CERITH, Seila adamst H. C. Lea, ¥Y% inch (Me2ssa- chusetts to Texas, south), p. 158. CHESNEL’S RISSOINA, Rissoina chesneli Mich., 1/5 inch (North Carolina to Wexas, south) p-lai- VARIABLE DWARF OLIVE, Olivella mutica Say, '/3 inch (North Carolina to Texas, south), p. 246. MAUGERI'S ERATO, Erato maugeriae Gray, '/16 inch (North Carolina to West Indies), p. 176. JASPER CONE, Conus jaspideus Gmelin, 34 inch (Florida and West Indies), pa 202: STEARNS’ CONE, Conus stearnsi Conrad, 4 inch (Florida to Mexico), p. 262. WARTY CONE, Conus verrucosus Hwass, 34 inch (Southeastern Florida and West Indies), p. 263. a. d. ae Le PLATE 23 ATEANTIG COAST UNIVAEMES QUEEN CONCH, Sirombus gigas L., 10 inches (also young) (Florida Keys and West Indies), p. 174. MILK CONCH, Strombus costatus Gmelin, 6 inches (Southern Florida and West Indies). yp. 74. AMERICAN PELICAN’S FOOT, Aporr- hais occidentalis Beck, 2 inches (also young) (off New England), p. 173. LONGLEY’S CARRIER-SHELL, Xeno- phora longleyt Bartsch, 7 inches (Gulf of Mexico, south), p. 173. CARIBBEAN CARRIER-SHELL, phora caribaea Petit, 4 inches Florida and Cuba), p. 173. GIANT TUN, Tonna galea L., 6 inches (North Carolina to ‘Texas and West Indies; Pacific), p. 199. CROSSE’S ‘TUN, Eudoliwm crosseanum Montero., 3 inches (off New Jersey to West Indies), p. 199. Xeno- (off WEST INDIAN CROWN CONCH, Melongena melongena L., 4 inches (Florida Keys, south), p. 235. KNOBBED WHELK, Busycon carica Gmelin, 8 inches (Cape Cod, Massa- chusetts. to Northeastern — Florida), Pp 2o0. NEW ENGLAND NASSA, Nassarius trivit- tatus Say, % inch (Nova Scotia to South Carolina), p. 239. PERVERSE WHELK, Busycon perversum L., form eliceans Mont., 6 inches North- eastern Florida), p. 236. CARIBBEAN VASE, Vasuwm muricatum Born, 4 inches (South Florida and West Indies), p. 245. Wn. q- u. W. PYGMY COLUS, Colus pygmaea Gould, 1 inch (Quebec to off North Carolina), Pp. 229: CHANNELED WHELK, Busycon canalicu- latum L., 6 inches (Cape Cod to North- eastern Florida), p. 236. LIGHTNING WHELK, Busycon contra- rium Conrad, 8 inches (South Carolina fo) Wexas), p21 230: EASTERN MUD NASSA, Nassarius ob- soletus Say, 34 inch (Quebec to North- eastern Florida), p. 240. COMMON EASTERN NASSA, Nassarius vibex Say, 4% inch (North Carolina to Texas, south), p. 237. VARIABLE NASSA, Nassarius ambiguus Pult., ¥4 inch (North Carolina to West Indies)p. 239. BROWN-CORDED NEPTUNE, Neptunea decemcostata Say, 3 inches (Nova Scotia to Massachusetts), p. 229. HAIRY COLUS, Colus pubescens Verrill, 2 inches (Quebec to off North Caro- lina), p. 229. FAT COLUS, Colus ventricosus Gray, 24% inches (Nova Scotia to New York), not in text. EMPEROR HELMET, Cassis madagas- cariensis Lam., 9 inches (Southeastern Florida and West Indies), p. 193. LONGHORNED SMOKE SHELL, Typhis longicornis Dall, 44 inch (Florida and West Indies), not in text. STIMPSON’S COLUS, Colus stimpsoni Morch, 4 inches (Labrador to off North Carolina), p. .227. FLORIDA HORSE CONCH, Pleuroploca gigantea Kiener, 20 inches (North Caro- lina to Florida), p. 242. d. mM. Prarre 324 PACIFIC COAST UNIVALVES TWO-KEELED HAIRY-SHELL, Tricho- tropis bicarinata Sby., 144 inches (North Pacific and North Atlantic), p. 168. CANCELLATE HAIRY-SHELL, Tricho- tropis cancellata Hinds, 1 inch (Alaska to Oregon), p. 167. GRAY HAIRY-SHELL, Trichotropis in- stgnis Midd., 1 inca (Alaska to Japan), p- 168. BOREAL MHAIRY-SHELL, Trichotropis borealis B. and Sby., 34 inch (Arctic to Washington; also to Maine), p. 167. GEM MUREX, Murex gemma Sby., 1 inch (Santa Barbara to Lower California), p- 206. NUTTALL’S THORN PURPURA, Piero- rytis nuttalli Conrad, 11% inches (Cali- fornia to Lower California), p 219: OREGON TRITON, Argobuccinum ore- gonensis Redfield, 4 inches (Alaska to San Diego, California), p. 194. FOLIATED THORN PURPURA, Ptero- rytts foliata Gmelin, 3 inches (Alaska to San Pedro, California), p- 218. GIANT FORRERIA, Forreria belcheri Hinds, 5 inches (California to Lower California), p- 200. STUART’S TROPHON, Boreotrophon stuartt E. A. Smith, 2 inches (Alaska to Sen Diego, California), p. 207. PCULSON’S DWARF TRITON, Ocene- bra poulsont Cpr., 2 inches (Santa Bar- bara, California, to Lower California), p. 218. FESTIVE MUREX, Murex festivus Hinds, 2 inches (Morro Bay, California, to Lower California), p- 206. GRACEFUL DWARF TRITON, Ocenebra gracillima Stearns, 1/3 inch (Monterey, Calitoriass to. (Gulf) of California), BeeZile: Nn. p- u. LEWIS MOON-SHELL, Lunatia lewisi Gould, 4 inches (Canada to Lower California), p. 189. SPOTTED THORN DRUPE, Acanthina spivata Blainville, 1 inch (Washington to California), p. 211. LEFT-HANDED BUCCINUM, Volutop- stus harpa Morch, + inches (Alaska), p: 226: COMMON NORTHWEST NEPTUNE, Neptunea lyrata Gmelin, 5 inches (Arctic to Washington), p. 230. PRIBILOFF NEPTUNE, Neptunea pri- biloffensis Dall, 5 inches (Alaska to British Columbia), p. 230. FAT NEPTUNE, Neptunea~ ventricosa Gmelin, 3 inches (Arctic and Alaska), Pp. 250: GLACIAL BUCCINUM, Buccinum _ gla- ciale L., 3 inches (Arctic to Washington; also to Nova Scotia), p. 226. SILKY BUCCINUM, Buccinum tenue Gray, 2 inches (Arctic to Washington; also to Maine), p. 225. BAER’S BUCCINUM, Buccinum baer Midd., 114 inches (Bering Sea, Alaska), p- 226. KELLET’S WHELK, Kelletia kelleti For- bes, 4 inches (State Barbara, California, to Mexico), p. 231. LIVID MACRON, Macron lividus A. Ads., 1 inch (Monterey, California, to Lower California), p. 234. COOPER’S NUTMEG, Narona_ cooperi Gabb, 2 inches (Monterey, California, to Lower California), p. 253. SANTA BARBARA SPINDLE, Fusinus barbarensis ‘Trask, 4 inches (Oregon to California), p. 244. GIANT PANAMA SPINDLE, Fusinus dupetit-thouarsit Kiener, 6 inches (off Lower California), not in text. d. mM. PrATEee25> ATLANTIC COAST UNIVALVES FLORIDA ROCK-SHELL, Thais haema- stoma floridana Conrad, 2 inches (North Carolina to West Indies), p: 2h3: DELTOID ROCK-SHELL, Thais deltoidea Lam., 1 inch. (Southeastern Florida to Brazil), p. 214. ELEGANT FOSSARUS, Fossarus elegans Verr. and Smith, 3 mm (Massachusetts to North Carolina), p. 176. RED-MOUTHED ROCK-SHELL, Thais h. haemastoma L., 3 inches (Europe; South America), p. 213. SCALY *DOGWINKLE, Thais lapillus L., form imbricata Lam. (North Atlantic to New York), Prac: RUSTIC ROCK-SHELL, Thais rustica Lam., 114 inches (Southeastern Florida to Brazil), p. 214. ATLANTIC DOGWINKLE, Thais lapil- lus L., 1 inch (North Atlantic to New York) ip. 214 HEXAGONAL MUREX, Muriscopsis hexa- gona Lam., 1 inch (Florida Keys and West Indies), p. 209. MORCH’S PITTED MUREX, Murex cel- lulosus nuceus Morch, 1 inch (Florida to West Indies), p. 205. DALL’S PITTED MUREX, Murex cellu- losus leviculus Dall, % inch (North Carolina to West Florida), p. 205. DELTOID ROCK-SHELL, Thais deltoidea Lam., | inch (Southeastern Florida to Brazil) p.1214. WIDE-MOUTHED PURPURA, Purpura patula L., 3 inches (Southeastern Florida and West Indies); p2e23. LIP TRITON, Cymatium labiosum Wood, 3% inch (North Carolina to West In- dies), p. 196. DWARF HAIRY TRITON, Cymatium gracile Reeve, 1 inch (North Carolina to West Indies), p. 195. GRANULAR FROG-SHELL, Bursa gra- nularis Réding, 2 inches (Southeastern Florida, south), p- 198. CHESTNUT FROG-SHELL, Bursa spadi- cea Montfort, 2 inches (Southeastern Florida and Caribbean), p. 198. GOLD-MOUTHED TRITON, Cymatium chlorostomum Lam., 2 inches (South- eastern Florida, south), p. 196. W. ye aa. bb. GG dd. CEs oo oo hh. KNOBBED TRITON, Cymatium murici- num Ré6ding, 2 inches (Southeastern Florida and West Indies), p: 196: ATLANTIC WOOD-LOUSE, Morum onis- cus L., % inch (and young) (South- eastern Florida, south), p. 192. INTRICATE BAILY-SHELL, Bailya intri- cata Dall, 44 inch (south half of Flo- rida), p. 231. CANDE’S PHOS, Antillophos candei Orb., 1 inch (North Carolina to Cuba), p. 231. BLACKBERRY DRUPE, Drupa nodulosa C. B. Adams, % inch (Florida and West Indies), pe2 WHITE-SPOTTED ENGINA, Engina tur- binella Kiener, 14 inch (Florida Keys, south), p. 232. ARROW DWARF TRITON, Colubraria lanceolata Menke, 1 inch (North Caro- lina to West Indies), p. 232. TINTED CANTHARUS, Cantharus tinctus Conrad, 1 inch (North Carolina to West Indies), p. 233. FLORIDA DISTORSIO, Distorsio constricta mcegintyt Em. and Puff., 2 inches (North Carolina to Florida), p. 197. ATLANTIC DISTORSIO, Distorsio cla- thrata Lam., 2 inches (North Carolina to Texas, south), p. 196. COMMON DOVE-SHELL, Columbella mercatoria L., % inch (Southezstern Florida and West Indies), p. 220. RAVENEL’S DOVE-SHELL, Mfitrella ra- venelt Dall, ¥g inch (North Carolina to Florida), p. 223. GLOSSY DOVE-SHELL, Nitidella nitidula Sby., 4 inch (Southeastern Florida and West Indies), p. 222. GREEDY DOVE-SHELL, Anachis avara Say, 14 inch (New Jersey to Texas), p: 221: WELL-RIBBED DOVE-SHELL, Anachis translirata Ravy., 1/3 inch (Massachusetts to” Texas; south) pps sai LUNAR DOVE-SHELL, Mitrella lunata Say, */16 inch (Massachusetts to ‘Texas, south), p. 223. WHITE-SPOTTED DOVE-SHELL, WNiti- della ocellata Gmelin, 14 inch (Florida Keys and West Indies), p. 222. d. m PrAtE.26 MELANTIC COAsSe, UNIVALVES SULCATE MITER, Mitra sulcata Gmelin, ¥4 inch (Southeastern Florida to West Indies), p. 249. BEADED MITER, Mitra nodulosa Gmelin, 1 inch (North Carolina to West Indies), Die2ao: HENDERSON’S MITER, Mitra hender- sont Rehder, 34 inch. Holotype (South- eastern Florida, south), p. 249. BARBADOS MITER, Mitra barbadensis Gmelin, | inch (Southeastern Florida to West Indies), p. 249. WHITE-RIBBED, Mitra albicostata C. B. Adams, 14 inch (Florida Keys and West Indies), not in text. WHITESPOTTED DRILLIA, Monilispira albomaculata C. B. Adams, 1% inch (West Indies), p. 271. GRAY ATLANTIC AUGER, Terebra cinerea Born, 114 inches (Southeastern Florida to West Indies), p. 266. SHINY ATLANTIC AUGER, Terebra hastata Gmelin, 11% inches (South- eastern Florida to West Indies), p. 266. COMMON ATLANTIC AUGER, Terebra dislocata Say, 14 inches (Virginia to Texas, south), p. 265. CONCAVE AUGER, Terebra concava Say, 3% inch (North Carolina to West Florida), p. 266. FINE-RIBBED AUGER, Terebra protexta Conrad. 1 inch (North Carolina to Texas), p. 266. SPINED SPINDLE-BUBBLE, Rhizorus acutus Orb., 3 mm (North Carolina to West Indies), p. 281. WATSON’S CANOE-BUBBLE, Scaphander watsont Dall, 34 inch (off North Caro- lina to Florida), p. 281. Nn. P:- u. W. GYSTER TURRET, Crassispira ostrearum Stearns, 14 inch (North Carolina to Cuba), p. 270. GIANT CANOE-BUBBLE, Scaphander punctostriatus Mighels, 1! inches (off entire coast), p. 281. COMMON WEST INDIAN BUBBLE, Bulla occidentalis A. Adams, 34 inch (North Carolina to West Indies), p. 277. ORBIGNY’S BARREL-BUBBLE, Cylichna bidentata Orb., 3 mm (North Carolina to ‘Texas, south), p. 282. GOULD’S BARREL-BUBBLE, Cylichna gould: Couthouy, 3g inch (Arctic to Massachusetts), p. 282. EASTERN PAPER-BUBBLE, Haminoea solitaria Say, ¥4 inch (Massachusetts to North Carolina), p. 279. ADAM’S BABY-BUBBLE, Acteon puncto- striatus C. B. Adams, 5 mm (Massa- chusetts to West Indies), p. 275. MINIATURE MELO, Micromelo undata Brug., 14 inch (Florida Keys and West Indies); p: 276: ORBIGNY’S HELMET-BUBBLE, Ringzi- cula_ semistriata Orb., 3 mm_ (North Carolina to West Indies), p. 276. BUSH’S BARREL-BUBBLE, Pyrunculus caelatus Bush, 3 mm (North Carolina to Southeastern Florida), p. 280. CHANNELED BARREL-BUBBLE, Retusa canaliculata Say, 5 mm _ (Nova Scotia to Texas, south), p. 280. COMMON PAPER NAUTILUS, Argo- nauta argo L., 5 inches. Shell of female filled with eggs (Tropical Seas), p. 485. b. Pearse 2 7 AEEAN TIC GOAST BIVAIEV-ES COMMON AWNING CLAM, velum Say, 3% inch (Nova Florida), p. 333. SHORT YOLDIA, Yoldia sapotilla Gould, Solemya Scotia to 1 inch (Arctic to North Carolina), p20; POURDALES” iGEASS* SGALEOR, Pro- peamussitum pourtalesianum Dall, % inch (off Florida), p. 369. MYALIS YOLDIA, Yoldia myalis Couthouy, 1 inch (Arctic to Cape Cod), Pa oaU: BROAD YOLDIA, Yoldia_ thraciaeformis Storer, 2 inches (Arctic to North Caro- lina; also Alaska), Pr oa0: SULCATE LIMOPSIS, Limopsis sulcata V. and B., 4% inch (Massachusetts to West Indies), p. 347. UNDULATE BITTERSWEET, Glycy- meris undata L., 2 inches (North Caro- lina to West Indies), p. 348. DECUSSATE BITTERSWEET, Glycy- meris decussata L., 2 inches Florida and West Indies), p. 348. COMB BITTERSWEET, Glycymeris pec- tinata Gmelin, 34 inch (North Carolina to West Indies), p. 348. MOSSY ARK, Arca umbonata Lamarck, 2 inches (North Carolina to West In- dies) ip.o42. DOC BALES’ ARK, Barbatia tenera C. B. Adams, | inch (Florida and West In- dies) para29. ICELAND SCALLOP, Chlamys islandica Miller, 3 inches (Arctic to Massa- chusetts; also to Washington), p. 365. m. ATLANTIC DEEPSEA SCALLOP, Placo- pecten magellanicus Gmelin. 9 inches (Labrador to North Carolina), p. 366. ~ (=) q- u. W. TURKEY WING, Arca zebra Swainson, 3 inches (North Carolina to West In- dies); p. 342: CUT-RIBBED ARK, Anadara lienosa flo- ridana Conrad, 4 inches (North Caro- lina to Wexas); sp. 344. EARED ARK, Anadara notabilis Réding. 2 inches (Florida to Brazil), Pp: oa RED-BROWN ARK, Barbatia cancellaria Lam., 1 inch (Florida and West Indies), jon Gey WHITE BEARDED ARK, Barbatia can- dida Helbling, 2 inches (North Caro- lina to Brazil), p. 342. TRANSVERSE ARK, Anadara_ transversa Say, 1 inch (Cape Cod to Texas), p. 345. BLOOD ARK, Anadara ovalis Brug., 2 inches (Cape Cod to Texas and West Indies), p. 345. WHITE MINIATURE ARK, Barbatia domingensis Lam., 44 inch (North Ca- rolina to West Indies), p. 343. SAW-TOOTHED PEN SHELL, Atrina serrata Sby., 6 inches (North Carolina to Florida), p. 360. AMBER PEN SHELL. Pinna carnea Gmelin, 5 inches (Florida and West Indies), p. 360. STIFF PEN SHELL, Atrina rigida Solan- der, 7 inches (North Carolina to West Indies), p. 300. INCONGRUOUS ARK, dAnadara brasiliana Lam., 2 imches (North Carolina to Wexas ‘to: Brazil) po. 340: PONDEROUS ARK, Noetia ponderosa Say, 2 inches (Virginia to Texas), p. 346. ee ae Ted ce eee! fp PLATE 28 MC ANTIG COAST BIVAEV ES COMMON EASTERN OYSTER, Crasso- strea virginica Gmelin, 3 inches (entire Atlantic Coast), p. 375. SPONGE OYSTER, Ostrea permollis Sby., 2 inches (North Carolina to West In- dies); p. 374: CRESTED OYSTER, Ostrea equestris Say, 2 inches (North Carolina to West In- dies), sp.373: COON OYSTER, Ostrea frons L., 2 inches. Two forms. (Florida and West Indies), Pp: 075. DISCORD MUSCULUS, Musculus discors L., 1 inch (North Atlantic and North PACHIC).. py 300. SMOOTH MUSCULUS, Musculus laevi- gatus Gray, 1 inch (North Atlantic and INorthePacitic), p= 395: BLACK MUSCULUS, Musculus niger Gray, 2 inches (Arctic to North Caro- lina; also to Washington), p. 355. ATLANTIC RIBBED MUSSEL, Modiolus demissus Dillwyn, 3 inches (Canada to South Carolina), p. 351. ATLANTIC PAPER MUSSEL, Amygdalum papyria Conrad, 1 inch (Maryland to Mlexas)) pp. 309; GLANDULAR CRENELLA, Crenella glandula ‘Yotten, 1/3 inch (Labrador to North Carolina), p. 350. GIANT DATE MUSSEL, Lithophaga an- tillarum Orb., 4 inches (Gulf of Mexico, south), p. 357. FLATTENED CARDITA, Venericardia perplana Conrad, 4% inch (North Caro- lina to Florida), p. 380. m. oO. p- q. u. BLACK DATE MUSSEL, Lithophaga nigra Orb., 2 inches (Florida and West In- dies), p.7s00: MAHOGANY DATE MUSSEL, Litho- phaga bisulcata Orb., 1 inch (Florida to Argentina), p. 357. LENTIL ASTARTE, Astarte suwbequilatera Sby., 1 inch (Arctic Seas to off Georgia), p: 3/6, CORAL-BORING CLAM, Coralliophaga coralliophaga Gmelin, 1% inches (Gulf and West Indies), p. 382. BOREAL ASTARTE, Astarte borealis Schumacher, 114 inches (Arctic to Massachusetts; to Alaska), p. 375. WAVED ASTARTE, Astarte undata Gould, | inch (Gulf of Maine), p. 376. SMOOTH ASTARTE, Astarte castanea Say, 1 inch (Nova Scotia to Cape Cod, Massachusetts), p. 376. NORTHERN CARDITA, Venericardia borealis Conrad, 1 inch (Labrador to North Carolina), p. 379. GLASSY LYONSIA, Lyonsia hyalina Con- rad, 14 inch (Nova Scotia to South Ca- rolina), p. 468. LEA’S SPOON-CLAM, Periploma leanum Conrad, 1 inch (Nova Scotia to North Carolina), p. 474. PAPER SPOON CLAM, Periploma papyra- lium Say, 1 inch (Labrador to Rhode Island), p. 472. UNEQUAL SPOON CLAM, Periploma inequale C. B. Adams, 1 inch (South Carolina to Texas), p. 473. CONRAD’S THRACIA, Couthouy, 3 inches New York), p. 471. Thracia conradi (Nova Scotia to d. m. PLATE 29 ATLANTIC COAST BIVALVES GIANT ROCK SCALLOP, Hinnites multi- rugosus Gale, 7 inches (Alaska to Lower California), p. 369. GIANT PACIFIC SCALLOP, Pecten cau- rinus Gould, 7 inches (Alaska to Cali- fornia), p. 361. IBUCMOMEUUOIE SS ILIOMUAN Hert. and Strong, 1 to Mexico), p. 371. FALSE JINGLE SHELL, Pododesmus macroschismus Desh., 3 inches (Alaska to Lower California), p. 372. PERUVIAN —JINGCIEE, SHELE, peruviana Orb., 2 fo. Peru), ps 372. NATIVE PACIFIC OYSTER, Ostrea lurida Cpr., 3 inches (Alaska to Lower California), p. 374. GIANT PACIFIC OYSTER, Crassostrea gigas Thunberg, 8 inches (Canada _ to California), p. 375. CALIFORNIAN DATE MUSSEL, Botula californiensis Phil., 1 inch (California south), p. 356. KELSEY’S DATE MUSSEL, Lithophaga plumula kelseyi Hert. and Strong, | inch (California), p. 357. SCISSOR DATE MUSSEL, Lithophaga aristata Dill., 1 inch (Florida and Cali- fornia, south), p. 357. FALCATE DATE MUSSEL, Botula fal- cata Gould, 3 inches (Oregon to Lower California), p. 356. STOUT CARDITA, Venericardia ventri- cosa Gould, % inch (Washington to California), p. 379. NORTHERN UGLY CLAM, Entodesma saxicola Baird, 4 inches (Alaska to Cali- fornia), p: 469: Lima inch hemphilli (California Anomia inches (California n. p- q- u. Ww. CALIFORNIAN SUNSET CLAM, Gavi californica Conrad, 3 inches (Alaska to California), p. 441. CALIFORNIAN TULIP MUSSEL, Modio- lus fornicatus Cpr., 1 inch (California), De 02: CALIFORNIAN MUSSEL, Mytilus califor- nianus Conrad, 8 inches (Alaska to Miexico); sp. 354; NUTTALL’S BLADDER CLAM, Myitili- meria nuttalli Conrad, 1 inch (Alaska to Lower California), p. 469. CARPENTER’S CARDITA, Cardita car- penteri. Lamy, % inch (Canada to Lower California), p. 378. PURPLISH PACIFIC TAGELUS, Tagelus subteres Cpr., 2 inches (California to Lower California), p. 441. ROCK-DWELLING SEMELE, Semele rupicola Dall, 1 inch (California to Mexico), p. 435. CALIFORNIAN TAGELUS, Tagelus californianus Conrad, 3 inches (Cali- fornia to Panama), p. 440. BLUNT JACKKNIFE CLAM, Solen stca- rius Gould, 3 inches (Canada to Lower California), p. 444. ROSE PETAL SEMELE, Semele rubro- picta Dall, 2 inches (Alaska to Mexico), Patou: NUTTALL’S MAHOGANY CLAM, San- guinolaria nuttalli Conrad, 3 inches, (California to Lower California), p. 439. PACIFIC RAZOR CLAM, Siliqua patula Dixon, 5 inches (Alaska to California), JO Gs39p BARK SEMELE, Semele decisa Gould, 3 inches (San Pedro, California to Lower California), p. 435. Gl. og h.e m. PLATE 30 ATEAN FIG iCOASE BIVAIEY ES BROAD-RIBBED CARDITA, Cardita flo- ridana Conrad, 1 inch (Florida to Mexico), p. 378. LINDSLEY’S CRASSINELLA, Crassinella mactracea Lindsley, 1/3 inch (Massa- chusetts to New York), p. 377. NORTHERN DWARF COCKLE, Cerasto- derma pinnulatum Conrad, 1% inch (Labrador to North Carolina), p. 404. STOUT ‘TAGELUS, Tagelus plebeius Solander, 3 inches (Cape Cod to Texas), p- 440. ATLANTIC RUPELLARIA, Rupellaria typica Jonas, 1 inch (North Carolina to the West Indies), p. 420. ATLANTIC RAZOR CLAM, Siliqua cos- tata Say, 2 inches (Canada to New Jiexsey)s p22. PURPLISH TAGELUS, Tagelus divisus Spengler, 1 inch (Cape Cod to Mexico), jopededl) SMALL FALSE DONAX, Heterodonax bimaculatus Linné, 34 inch (Florida and 4 West Indies), p. 441. ST. MARTHA’S RAZOR CLAM, Sole- curtus sanctaemarthae Orb., 114 inches (North Carolina to Brazil), p. 445. CANCELLATE SEMELE, Semele bellastyri- ata Conrad, 14 inch (North Carolina to West Indies), p. 435. ATLANTIC JACKKNIFE CLAM, Ensis directus Conrad, 8 inches (Labrador to South Carolina), p. 443. DWARF TIGER LUCINA, Codakia orbi- culata Montagu, 34 inch (North Caro- lina to West Indies), p. 391. CROSS-HATCHED LUCINA, Dvivarvicella quadrisulcata* Orb., 3% inch (Massa- chusetts to West Indies), p. 391. GREEN JACKKNIFE CLAM, Solen viridis Say, 2 inches (Rhode Island to ‘Texas), Puta: oO. P- q. u. aa. FLORIDA LUCINA, CRESTED TELLIN, Tellidora Recluz, 1 inch (North Mexas), p. 1430: DENTICULATE WEDGE SHELL, Donax denticulata Linné, | inch (West Indies), p- 438. TEXAS WEDGE SHELL, Donax bilis roemert Philippi, 34 coast), p. 437. COQUINA SHELL, Donax variabilis Say, 3%4 inch (Virginia to Texas), p. 437. GRANULAR POROMYA, Poromya gra- nulata Nyst, 1/3 inch (Massachusetts to Cuba), p. 475. GRANT AND GALE MACOMA, Macoma cristata Carolina to varia- inch (Texas planiuscula Grant and Gale, 1 inch (Arctic to Oregon), p. 433. MEROPSIS TELLIN, Tellina meropsis Dall, 4% inch (San Diego, California, south), p. 426. COMMON ATLANTIC ABRA, Abra aequalis Say, 4% inch (North Carolina to Texas, and south), p. 437. DALL’S LITTLE ABRA, Abra lioica Dall, 4 inch (off Massachusetts to West In- dies), p. 437. NORTHERN DWARF TELLIN, Tellina agilis Stimpson, 1/3 inch (Canada to Maryland), p. 422. FLORIDA MARSH CLAM, Pseudocyrena floridana Conrad, 1 inch (West Florida to Texas), p. 381. GIBB’S CLAM, Eucrassatella speciosa A. Ads., 2 inches (North Carolina to West Indies); pp. ait. Lucina (West floridana Conrad, 114 inches Florida to Wexas); p:/ 307: bb. CAROLINA MARSH CLAM, Polymesoda caroliniana Bosc, Mexas) Spys8le 1 inch (Virginia to d. PLATE 31 PACIFIG COAST BIVALVES GIANT PACIFIC COCKLE, Trachycar- dium quadragenarium Con., 5 inches (California), p. 398. NUTTALL’S COCKLE, Clinocardium nuttalli Conrad, 4 inches (Alaska to California), p. 403. CALIFORNIAN LUCINA, Codakia cali- fornica Conrad, 14% inches (California), pe 90: FRILLED VENUS, Chione gnidia Brod. and Sby., 3 inches (Lower California tower), mot, im text: PAGIFIG COAST BITTERSWEET, Gly- cymeris subobsoleta Cpr., | inch (Alaska to Lower California), p. 349. SMOOTH PACIFIC VENUS, myax subdiaphana Cpr., 2 inches (Alaska to Lower California), p. 411. NUTTALL’S LUCINA, Phacoides nuttalli Con., 1 inch (Santa Barbara, California, south), p. 388. PISMO CLAM, Tivela stultoruwm Mawe, 5 inches (San Mateo, California south), Pa a2 FRILLED CALIFORNIAN VENUS, Chione calif. undatella Sby., 2 inches (California, south), p- 408. COMMON CALIFORNIAN VENUS, Chione californiensis Brod., 2 inche; (San Pedro, California, south), p. 407. SMOOTH PACIFIC VENUS, Chione fluc- tifraga Sby., 214 inches (San Pedro, California, south), p- 408. COMMON WASHINGTON CLAM, Saxi- domus nuttalli Con., 4 inches (Alaska to Lower California), p. 417. Com pso- m. u. W. and n. COMMON PACIFIC LITTLE- NECK, Protothaca staminea Con., 2 inches (entire Pacific Coast), p. 410. WHITE ROCK VENUS, P. staminea form ruderata Desh (most common in Alaska), ps 410: CALIFORNIAN WEDGE SHELL, Donax californicus Con., | inch (Santa Barbara, California, south), p. 438. COMMON PACIFIC WEDGE SHELL, Donax gouldi Dall, % inch (California to Mexico), p. 438. CALIFORNIAN IRUS VENUS, Jrus lamel- lifera’ Conrad, 1 inch (California), Peala2. WAVY PACIFIC THRACIA, Cyathodonta undulata Con., 1 inch (California to Mexico), p. 472. WEST COAST RUPELLARIA, Rupel- laria tellimyalis Cpr., 1 inch (Califor- nia to Mexico), p. 420. MODEST TELLIN, Tellina modesta Cpr., ¥% inch (Alaska to Lower California), p- 425. CALIFORNIA CUMINGIA, Cumingia californica Conrad, 1 inch (California to Chili), p. 436. STIMPSON’S SURF CLAM, Spisula poly- nyma form alaskana Dall, 4 inches (Alaska), p. 446. COMMON PACIFIC SPOON CLAM, Periploma planiusculum Sby., 1 inch (California to Peru), p. 473. SALMON TELLIN, Tellina salmonea Cpr., Y4 inch (Alaska to California), p. 426. PACIFIC GAPER, Schizothaerus nuttalli Conrad, 7 inches (Washington to Lower California), p. 450. mM. PLATE .32 ATLANTIGTEGOAST BIVALMVES GIANT ATLANTIC COCKLE, Dinocar- dium robustum Solander, 4 inches (Virginia to Texas), p. 401. VANHYNING’S GIANT COCKLE, D. ro- bustum vanhyningt Cl. and Smith, 4 inches (West Florida), p. 401. ERIEEED) "PAPER \COCKLE? (apyrndea semisulcata Sby., 1% inch (Florida and West Indies), p. 398. GREENLAND COCKLE, Serripes groen- landicus Brug., 3 inches (Quebec to Massachusetts; Alaska), p. 401. ICELAND COCKLE, Clinocardium cilia- tum Fabr., 3 inches (Arctic to Massa- chusetts; also to Washington), p. 403. OCEAN QUAHOG, Arctica islandica L., 3 inches (Arctic to off North Carolina), p- 381. SOUTHERN QUAHOG, Mercenaria campechiensis Gmelin, 5 inches (and young) (Virginia to Florida), p. 406. NORTHERN QUAHOG, Mercenaria mer- cenaria L., 4 inches (Canada to east Florida), p. 406. GRAY PYGMY VENUS, Chione grus Hol- mes, #¢ inch (North Carolina to Louisi- ana), p. 408. ROSTRATE CUSPIDARIA, Cuspidaria rostrata Spengler, 4% inch (Massachusetts to West Indies), p. 476. TEXAS VENUS, Callocardia texasiana Dall, 3 inches (Gulf of Mexico), p. 416. MORRHUA VENUS, Pitar morrhuana Linsley, 114 inches (Canada to North Carolina), p. 414. PRINCESS VENUS, Antigona listeri Gray, 3 inches (Southeastern Florida and West Indies), p- 404. n. p- u. Ww. QUEEN VENUS, Antigona rugatina Heil- prin, 1144 inches (North Carolina to West Indies), p. 405. DWARF SURF CLAM, Mulinia lateralis Say, 1/3 inch (Maine to Texas), p. 449. ATLANTIC SURF CLAM, Spisula solidis- sima_ Dill., 6 inches (Nova Scotia to South Carolina), p. 446. CHANNELED DUCK CLAM, Labiosa plicatella Lam., 3 inches (North Caro- lina to West Indies), p. 449. ARCTIC WEDGE CLAM, Mesodesma arctata Con., 114 inches (Greenland to Virginia), p. 451. FRAGILE ATLANTIC MACTRA, Mactra fragilis Gmelin, 2 inches (North Caro- lina to West Indies), p. 445. CAMPECHE ANGEL WING, Pholas cam- pechiensis Gmelin, 3 inches (North Carolina to Mexico), p. 462. GIANT FALSE DONAX, Iphigenia bra- siliensis Lam., 214 inches (Florida and West Indies), p. 439. TRUNCATE GAPER CLAM, Mya _ trun- cata L., 2 inches (Arctic to Massa- chusetts; also to Washington), p. 455. STRIATE MARTESIA, Martesia striata L., 1 inch (Florida and West Indies), Parton: COMMON SOFT-SHELL CLAM, Mya arenaria L., 4 inches (Labrador to North Carolina), p. 455. ATLANTIC GROOVED MACOMA, Apo- lymetis intastriata Say, 2 inches (Florida and West Indies), p. 434. FALSE ANGEL WING, Petricola pholadi- formis Lam., 2 inches (Canada to West Indies), p. 420. Ree Oe tig: AM aS BG A res MURICIDAE 211 Muricopsis ostrearum Conrad Mauve-mouth Drill ; Figure 47g West coast of Florida to the Florida Keys. 1 inch in length, extraordinarily like Urosalpinx perrugata, but more elongate, with a longer siphonal canal which is bent slightly back, and with a light-mauve aperture. Moderately common from low tide area to 35 fathoms. M. floridana Conrad is this species. Genus Pseudoneptunea Kobelt 1882 Pseudoneptunea multangula Philippi False Drill Figure 47f North Carolina to both sides of Florida and the West Indies. 1 to 1/4 inches in length, rather broad, with a short, fairly open siphonal canal. Outer lip sharp, finely crenulated. At the base of the columella there is a single, small fold. 8 to 9 short, rounded axial ribs on the periphery of the whorl. Spiral cords weak. Color gray with red-brown specklings; some- times solid yellow-orange. Moderately common, Subfamily PURPURINAE Genus Drupa Réding 1798 Subgenus Morula Schumacher 1817 Drupa nodulosa C. B. Adams Blackberry Drupe Plate 25v South half of Florida and the West Indies. % to 1 inch in length, elongate, grossly studded with round, black beads. Aperture purplish black. Outer lip thick, and with 4 to 5 relatively large, white beads. A common shallow-water species found under rocks. Genus Acanthina Fischer von Waldheim 1807 Subgenus Acanthinucella Cooke 1918 Acanthina spirata Blainville Spotted Thorn Drupe Plate 24-0 Puget Sound to San Diego, California. 1 to 1% inches in length, rather low-spired, solid, smoothish, except for numerous, poorly developed, spiral threads. Spine on lower, outer lip is strong, behind which on the base of the outside of the body whorl is a weak, spiral groove. Whorls slightly shouldered. Color bluish gray with numerous rows of small, red-brown dots. Aperture within is bluish white. A round- shouldered, smaller form (punctulata Sby. or Japilloides Conrad) is found 212 American Seashells from Monterey to Lower California. A common southern species found above high-tide mark on rocks; also on mussel beds. Acanthina paucilirata Stearns Checkered Thorn Drupe San Pedro, California, to Lower California. ¥ to % inch in length, characterized by about 6 spiral rows of small squares of black-brown on a cream-white background. Early whorls cancel- late, later whorls smoothish except for 4 or 5 very small, smooth, raised, spiral threads. Top of whorl slightly concave. Spine at base of outer lip small and needle-like. Aperture dentate, brownish with black squares on the outer lip. Siphonal canal short. Common above high-tide mark in southern California. Genus Urosalpinx Stimpson 1865 Urosalpinx cinerea Say Atlantic Oyster Drill Figure 47¢ Nova Scotia to southern Florida. Introduced to San Francisco and to England. % to 1 inch in length; without varices; outer lip slightly thickened on the inside and sometimes with 2 to 6 small, whitish teeth. Siphonal canal moderately short and straight. With about 9 to 12 rounded, axial ribs per whorl and with numerous, strong, spiral cords. Color grayish or yellowish white, often with irregular, brown, spiral bands. Aperture tan to dark-brown. This common species is very destructive to oysters. It occurs from intertidal areas down to about 25 feet or more. Females grow faster and hence are larger than the males. They may reach an age of 7 years. The drills move inshore to spawn. Each female spawns once a year (May to September in Virginia; June to September in Canada and England). The female deposits 25 to 28 leathery, vase-shaped capsules, each containing 8 to 12 eggs. U. fol- lyensis B. Baker is an ecologic form. Urosalpinx perrugata Conrad Gulf Oyster Drill Figure 47d West coast of Florida (to Louisiana? ). Similar to cinerea, but with 6 to 9 axial ribs which are quite large at the periphery of the whorl. The spiral cords are fewer and stronger. Aperture rosy-brown or yellow-brown. Outer lip more thickened on the inside and usually with 6 small, whitish teeth. This may be a subspecies of cinerea. Common on mudflats. Always compare with Muricopsis ostrearum Conrad which resembles this species very closely, MURICIDAE 213 Urosalpinx tampaensis Conrad Tampa Drill Tampa Bay area, west Florida. % to 1 inch in length; the light-brown aperture is thickened and the outer lip has 6 small, white teeth. With about 9 to 11 sharp, axial ribs per whorl, crossed by about 9 to ro equally strong spiral cords on the last whorl, thus giving the shell a cancellate sculpture. The whorls in the spire show only 2 spiral, nodulated cords, Exterior dark-gray, Common on mudflats. Genus Purpura Bruguiere 1789 Purpura patula Linné Wide-mouthed Purpura Plate 25] Southeast Florida and the West Indies. 2 to 3% inches in length, without an umbilicus. Exterior dull, rusty- gray. Columella salmon-pink. Inner borders of aperture with splotches of blackish brown. Common in the West Indies, uncommon in Florida. The animal exudes a harmless liquid which stains the hands and collecting bag a permanent violet. . The subspecies pansa Gould (west coast of Mexico south to Columbia) is similar in most respects, but the columella js colored a whitish cream. Genus Thais Roding 1798 Subgenus Stramonita Schumacher 1817 Thais haemastoma floridana Conrad Florida Rock-shell Plate 25a North Carolina to Florida, and the Caribbean. 2 to 3 inches in length, solid, smooth to finely nodulose. Color light- gray to yellowish with small flecks and irregular bars of brownish. Interior of aperture salmon-pink, often with brown between the denticulations of the outer lip. Running inside the aperture high up on the body whorl above the parietal area, there is a strong spiral ridge. Some specimens have a faint fold or plica on the base of the columella. This is a very common species, but quite variable in shape and color pattern. Typical haemastoma Lamarck oc- curs in the Mediterranean and West Africa. See additional remarks under Thais rustica. Thais haemastoma haysae Clench Hays’ Rock-shell Northwest Florida to Texas. This subspecies is characterized by its large size (up to 4% inches in 214 American Seashells length), strongly indented suture, and rugose sculpture with a row of double, strong nodules on the shoulder of the whorls. M. D. Burkenroad (1931) has given a long account of the biology of this oyster pest. Thais rustica Lamarck Rustic Rock-shell Plate 25f Southeast Florida and the West Indies. Bermuda. 1% inches in length, irregularly sculptured with 2 spiral rows of blunt spines, one on the shoulder, the other at the center of the body whorl. Color dirty-gray to dull mottled brown. Interior of aperture whitish but generally margined with spots of dark-brown along the outer lip. Parietal wall glossy- white. This species is smaller and more nodulose than floridana and always has a white aperture. Erroneously called Thais undata Lamarck which is an Indo-Pacific species. Three confusing species are often found together in southern Florida. The young of Cantharus tinctus (see p. 233) has the lower third of its white columella turned away (to the left) 20 degrees from the axis of the shell, and its early whorls in the spire are not shouldered. Thais haemastoma floridana is characterized by its almost straight, cream to orange columella, and by the numerous raised cream or white spiral ridges on the inside of the outer lip. Thais rustica has a stouter, white columella which is slightly twisted and purple-stained at the lower, inner corner. Its outer lip teeth occur in groups of 2 or 3 and near the edge of the lip are stained by heavy blotches of purple- brown. Subgenus Mancinella Link 1807 Thais deltoidea Lamarck Deltoid Rock-shell Plate 25b, k Jupiter Inlet, Florida, to the West Indies. Bermuda. 1 to 2 inches in length, heavy, and coarsely sculptured with two spiral rows of large, blunt spines. Parietal wall tinted with lavender, mauve or rose. Interior of aperture glossy-white. Exterior grayish white with mottlings of black or dull brown. Columella with a small but distinct ridge at the base which forms the margin of the siphonal canal. This is an abundant species where intertidal rocks are exposed to the ocean surf. Subgenus Polytropa Swainson 1840 Thais lapillus Linné Atlantic Dogwinkle Plate 25¢ Southern Labrador to New York. Norway to Portugal. 1 to 2 inches in length, roughly sculptured or smoothish. Commonly MURICIDAE 215 with rounded, spiral ridges. Sometimes imbricated with small scales (form named imbricata Lamarck, pl. 25e). Color usually dull-white, but sometimes yellowish, orange or brownish. Rarely with dark-brown or blackish spiral bands. This species has also been known as Nucella lapillus. For biology see H. B. Moore (1936 and 1938). Ficure 48. Pacific coast Dogwinkles. a, Thais emarginata Deshayes, b and c, T. canaliculata Duclos; d, T. lima Gmelin; e to h, forms of T. lamellosa Gmelin. All about eae size. Thais lamellosa Gmelin Frilled Dogwinkle Figures 48e-h Bering Straits to Santa Cruz, California. 1% to 5 inches in length, solid, usually with a fairly high, pointed spire. Columella almost vertical and straight, not flattened. Size, details of shape, sculpturing and color very variable. White, grayish, cream or orange, some- times spirally banded. Smoothish or with variously developed foliated, axial ribs. Sometimes spinose. A very common rock-loving species. Formerly Purpura crispata Martyn. 216 American Seashells Thais canaliculata Duclos Channeled Dogwinkle Figure 48b, c Aleutian chain to Monterey, California. 1 inch in length, moderately globose, its spire higher than that of emar- ginata, but lower than that of Jamellosa. Columella arched, flattened below. Characterized by about 14 to 16 low, flat-topped, closely spaced, spiral cords on the body whorl. Suture slightly channeled. Color white or orange- brown, often spirally banded. Moderately common on rocks and mussel beds. Do not confuse with Jima from Alaska. Thais emarginata Deshayes Emarginate Dogwinkle Figure 48a Bering Sea to Mexico. 1 inch in length, with a rather short spire and with globose whorls. Aperture large. Columella strongly arched, and flattened and slightly con- cave below. Sculpturing variable, but characteristically with coarse spiral cords, usually alternatingly small and large. Cords often scaled or coarsely noduled. Exterior yellow-gray to rusty-brown, often with darker, narrow spiral bands. Interior and columella light- to chestnut-brown. Exceedingly common in many places along the coast where there are rocks. Thais lima Gmelin File Dogwinkle Figure 48d Alaska and Japan to northern California. 1 to 2 inches in length, very similar to canaliculata, but with 17 to 20 round-topped spiral cords, often smooth, sometimes minutely fimbriated. Cords often alternate in size. Color whitish or orange-brown, rarely banded. Common intertidally. Compare with canaliculata. Genus Ocenebra Gray 1847 Tritonalia Fleming 1828 may also be used as a name for this genus, al- though Ocenebra would seem to be the wiser choice and will probably be the final choice. Ocinebra is a misspelling. Ocenebra interfossa Carpenter Carpenter’s Dwarf Triton Figure 49a Alaska to Lower California. % to % inch in length, spire half the length of the shell; light-gray in color, delicately sculptured. 8 to 11 axial ribs on the body whorl crossed by about a dozen strong, microscopicaliy scaled spiral cords. The surface is MURICIDAE EN often fimbriated axially between the cords. Siphonal canal moderately long, usually sealed over. Littoral to several fathoms. Common. There are 2 named varieties of doubtful biological significance: atropurpurea Cpr. and clathrata Dall. Ficure 49. Dwarf Tritons of the Pacific coast. a, Ocenebra interfossa Cpr.; b, O. circumtexta Stearns; ec and d, O. Jurida Midd. All natural size. Ocenebra lurida Middendorft Lurid Dwarf Triton Figure 49c, d Alaska to Catalina Island, California. 1 to 1% inches in length; 5 to 6 whorls; moderately elongate spire whose whorls show the axial ribs more prominently than the numerous fine spiral threads. Suture well-impressed. Body whorl with 8 to ro rounded ribs which are strongest and shouldered just below the suture but which fade out below the periphery of the whorl. The smaller, smooth, spiral cords are elevated | and prominent, often with numerous tiny axial lamellae between them. 6 to 1 8 small teeth on the inside of the outer lip. Color variable, whitish to rusty- | brown, sometimes banded. Periostracum dark-brown and fuzzy. Siphonal | canal usually sealed over. Very common from northern California north. Littoral to 30 fathoms. | Ocenebra gracillima Stearns Graceful Dwarf Triton Plate 24m | Monterey, California, to the Gulf of California. ¥4 inch in length, similar to Jurida in shape; with 5 whorls, those in the ) spire weakly cancellate with the axial ribs the strongest. Last whorl without 218 American Seashells axial ribs, except for a rather strong, rounded varix behind the outer lip. Last whorl with about a dozen or so light-brown, spotted, spiral threads over a background of light yellowish gray. 3 to 5 fairly large teeth on the inside of the outer lip. Siphonal canal short, sealed over in adults. Periostracum thin, fuzzy, grayish with mauve-brown undertones. Interior of aperture light mauve-brown, usually with a whitish, spiral band on the middle of the body whorl. O. stearnsi Hemphill is the same. Very common in rocky rubble and on wharf pilings. Ocenebra circumtexta Stearns Circled Dwarf Triton Figure 49b Moss Beach, California, to Lower California. *4 to 1 inch in length, spire 4% the length of the shell. Characterized by very strong, rough spiral cords (15 on the body whorl, 6 on the whorls above). Under a lens the cords are seen to consist of arched, crowded, raised axial lamellae. The cords are often cream-white with the interspaces black- brown. Axial ribs wide, low, rounded and 7 to 9 per whorl. Some specimens are banded or have large, red-brown spots. A white form of this species was unnecessarily named citrica Dall. A very abundant species on rocks at low tide to 30 fathoms. Ocenebra poulsoni Carpenter Poulson’s Dwarf Triton Plate 24k Santa Barbara, California, to Lower California. 1 to 2 inches in length; a sturdy shell with a semi-gloss finish. 8 to 9 nodulated, rounded axial ribs per whorl crossed by numerous very fine, incised spiral lines and 4 or 5 larger, rounded, raised spiral cords. The latter make nodules on the ribs. Siphonal canal narrowly open. Periostracum thin, grayish or brownish and smoothish. When the periostracum is absent, the shell is glossy-white with numerous, fine spiral lines of dark- to yellow- brown. Aperture white. An exceedingly common species found in nearly every region on rocks and wharf pilings. Genus Pterorytis Conrad 1862 Pterorytis foliata Gmelin Foliated Thorn Purpura Plate 24h Alaska to San Pedro, California. 2 to 3 inches in length, with 3 large, thin, foliaceous varices per whorl which are finely fimbriated on the anterior side. Numerous spiral cords are rather prominent and of various sizes. Siphonal canal closed, its anterior tip turned up and to the right. Base of outer lip with a moderately strong spine. MAGILIDAE 219 Aperture white. Exterior white to light-brown. Common in the Puget Sound area and to the north on rocks near shore. Also down to 35 fathoms. Appears in some books as Purpura or Ceratostoma foliatum Martyn. Pterorytis nuttalli Conrad Nuttall’s Thorn Purpura Plate 24f Point Conception, California, to Lower California. 1% to 2 inches in length, similar to Pter. foliata (and somewhat resem- bling Ocenebra poulsoni), but with much more poorly developed varices, and with one prominent, noduled rib between each varix. Spine on outer lip usually long and sharp. Exterior yellowish brown, sometimes spirally banded. Siphonal canal closed along its length. A common littoral species in the southern part of its range. Genus Eupleura H. and A. Adams 1853 Eupleura caudata Say Thick-lipped Drill Figure 47b South of Cape Cod to south half of Florida. % to 1 inch in length; apex pointed; siphonal canal moderately long, almost closed, coming to a sharp point below. Last varix large, rounded and with small nodules. Inside of outer lip with about 6 small, bead-like teeth. Whorls with spiral cords and strong axial ribs. There are 4 to 6 axial ribs between the last 2 varices. E. etterae B. B. Baker is a large, ecologic form of this species. Eupleura sulcidentata Dall Sharp-ribbed Drill Figure 47c West coast of Florida. Similar to E. caudata, but with the spiral sculpture almost absent. There are only 2 or 3 axial ribs between the last 2 varices. The varices are thin and sharp, and the entire shell is slightly compressed laterally (has a more oval outline from an apical or top view than does caudata). The axial ribs are often sharp and may bear a small spine at the top. Color gray, chocolate- brown, tan or rarely pinkish, and sometimes with a narrow spiral brown band. Moderately common. E. stimpsoni Dall from deep water in the Gulf of Mexico is figured on p. 209. Family MAGILIDAE Genus Coralliophila H. and A. Adams 1853 Coralliophila abbreviata Lamarck Short Coral-shell Southeast Florida and the West Indies. 220 American Seashells 34 to 1% inches in length, solid, grayish white, rather misshapen, with rounded or squared shoulders, and with or without weak, rounded axial ridges. Spiral sculpture of crowded, variously sized spiral cords which are made up of numerous microscopic scales. Aperture enamel-white, rounded above and constricted into a short siphonal canal below. Umbilicus small, shallow and funnel-shaped. A common species found living in the bases of seafans. C. deburghiae Reeve is a deep-water form or species with long, tri- angular ribs projecting straight out from the periphery of the whorl. It is uncommon. Subgenus Latiaxis Swainson 1840 Coralliophila costata Blainville California Latiaxis Point Conception, California, to Panama. 1 to 1% inches in length, variable in shape and the development of frills and spines. Deep-water forms (called bindsi Carpenter) bear triangular, flat- tened, up-turned spines on the periphery of the whorl. Spiral cords are strongly scaled. Color light-gray with an enamel-white aperture. Moder- ately common offshore. A choice collector’s item. Superfamily BUCCINACEA Family COLUMBELLIDAE (Pyrenidae) Genus Columbella Lamarck 1799 Columbella mercatoria Linné Common Dove-shell Plate 25bb Southeast Florida and the West Indies. % to %4 inch in length, solid, squat, highly colored with white and brown, interrupted spiral bars over yellow, pink or orange background. Sometimes only maculated with one color (orange, brown or yellow). Outer lip thick, bearing about a dozen white teeth. A common shallow-water spe- cies frequently cast up on beaches. Not found on the west coast of Florida. Columbella rusticoides Heilprin Rusty Dove-shell Key West north along the west coast of Florida. Similar to C. mercatoria, but much more slender, smooth on the center of the body whorl, and with mauve-brown marks between the apertural teeth. Also more faintly colored and lacking spiral bars or lines of brown. Common down to 20 feet. COLUMBELLIDAE 221 Genus Anachis H. and A. Adams 1853 Anachis avara Say Greedy Dove-shell Plate 25ee New Jersey to both sides of Florida to Texas. %% to % inch in length, moderately elongate, with about a dozen smooth axial plications on the upper half of each whorl. Spiral, incised lines very weak or absent, but strong at the base. Aperture narrow, a little less than half the length of the shell. Weak, smooth varix present. The 3 nuclear whorls are smooth and translucent-white. Next few whorls with numerous axial riblets. Color yellowish brown to dark gray-brown over which may be seen a faint pattern of irregular, white, large dots. Sometimes with dark- brown specklings. 4 weak teeth inside inner lip. A very common low-tide mark species. Anachis obesa C. B. Adams Fat Dove-shell Virginia to Florida, the Gulf States and the West Indies. 4 to % inch in length, moderately wide, dull grayish with 1 or 2 sub- dued, spiral brown bands in some specimens. Small, sharp axial ribs are nu- merous; spiral incised lines numerous, not crossing ribs. Where asqa) tacky, strong, occasionally knobbed, spiral cord immediately below the suture. Varix large, smooth and rounded. Body whorl behind it usually smoothish. Parietal shield faintly developed, but with a sharp edge. Inner wall of outer lip with about 3 to 5 small teeth. The form ostreicola Melville from north- west Florida is dark-brown and with stronger spiral threads or wider incised lines. This is a common shallow-water species. Anachis translirata Ravenel Well-ribbed Dove-shell Plate 25ff Massachusetts to northeast Florida. Similar to avara, but with about twice as many axial ribs which run the entire depth of each whorl, and with strong incised spiral lines throughout. Outer lip with about a dozen tiny teeth. Color drab yellowish to brown, but sometimes with wide, subdued, spiral bands of darker brown. Dredged com- monly just offshore usually from 2 to 20 fathoms. Anachis penicillata Carpenter Penciled Dove-shell San Pedro to Lower California. ¥% inch in length, rather slender, with 6 whorls, of which the first 2 nuclear ones are smooth, the remainder with about 15 strong axial riblets per 222 American Seashells whorl, which are made slightly uneven by numerous very fine spiral threads. Color translucent-cream with sparse spottings of brown. Common under rocks between tide marks. Genus Nitidella Swainson 1840 Nitidella ocellata Gmelin White-spotted Dove-shell Plate 25hh Lower Florida Keys and the West Indies. % inch in length, smooth, characteristically dark black-brown with nu- merous small white dots which may be quite large just below the suture. Outer lip thick, with 5 or 6 small whitish teeth. Aperture short, narrow, purplish brown within. When beachworn, the color is reddish or yellowish brown. Common under rocks at low tide. Formerly known as cribraria Lamarck. Nitidella nitidula Sowerby Glossy Dove-shell Plate 25dd Southeast Florida and the West Indies. % inch in length, characterized by the long aperture (%4 that of the entire shell) and by the very glossy shell. Color whitish with heavy mot- tlings of light-yellow to mauve-brown. Outer lip with about a dozen small teeth. Common in the West Indies on rocks at low tide. Nitidella gouldi Carpenter Gould’s Dove-shell Plate 20m Alaska to San Diego, California. % inch in length, 7 whorls are smoothish and slightly convex. Spire almost flat-sided. Base of shell on exterior of canal with about 9 fine, incised spiral lines. Bottom of white columella with a single, low plait. Outer lip simple, sharp and often reinforced within by 4 or 5 weak pustules. Shell whitish with faint brown maculations, covered with a yellowish-gray peri- ostracum. Fairly common from just offshore to 300 fathoms. Nitidella carinata Sowerby Carinate Dove-shell San Francisco to Lower California. ¥ inch in length, glossy, brightly variegated with orange, yellow, white and brown. Shoulder of last whorl usually strongly swollen. Exterior of canal with about a dozen spiral, incised lines. Both ends of the aperture are stained dark-brown. Outer lip thickened, crooked, and with about a dozen small spiral threads or teeth inside. Fairly common in shallow water. N. COLUMBELLIDAE 2213 gausapata Gould (California to Alaska) is similar, but without the swollen shoulder. Genus Mitrella Risso 1826 Subgenus Astyris H. and A. Adams 1853 Mitrella lunata Say Lunar Dove-shell Plate 25¢¢ Massachusetts to Florida, Texas and the West Indies. %46 to %4 inch in length, glossy, smooth, translucent-gray and marked with fine, axial zigzag brown to yellow stripes. Base of shell with fine, in- cised spiral lines. Aperture constricted, slightly sinuate. Outer lip with 4 small teeth on the inside. No prominent varix. Nuclear whorls very small and translucent. Color sometimes milky-white or mottled in brown. A very common species found at low tide. Mitrella raveneli Dall Ravenel’s Dove-shell Plate 25cc North Carolina to both sides of Florida. ¥g inch in length, resembling /umata, but translucent-whitish, without the mottlings, normally a slightly larger shell, more elongate, with a longer siphonal canal, and with a rather thin outer lip which lacks the deep sinua- tion found in the upper portion of the outer lip as in /umata. Commonly dredged from 5 to go (rarely to 200) fathoms, Rarely washed ashore. Mitrella tuberosa Carpenter Variegated Dove-shell Alaska to the Gulf of California. % inch in length, slender, with a narrow, pointed, flat-sided spire. Shell smooth and usually glossy. Outer lip slightly thickened and with small teeth within. Color a translucent yellowish tan with opaque, light-brown flammules and maculations. Sometimes all brown with tiny white dots. Early whorls in worn specimens have a lilac tinge. Periostracum thin and translucent. Common in shallow water; 7 to 30 fathoms. M. variegata Stearns may be this species, Genus Amphissa H. and A. Adams 1853 This genus was formerly placed in the family Buccinidae. Ampbhissa versicolor Dall Joseph’s Coat Amphissa Figure 50a Oregon to Lower California. 224 American Seashells % inch in length, rather thin, but quite strong; surface glossy. 7 whorls. Suture well-impressed. Whorls in spire and upper third of body whorl with about 15 obliquely slanting, strong, rounded, axial ribs. Numerous spiral, incised lines are strongest on the base of the body whorl. Lower columella area with a small shield. Outer lip thickened within by about a dozen small white teeth. Color pinkish gray with indistinct mottlings of orange-brown. A common littoral to shallow-water species. Figure 50. Small whelks of the Pacific coast. a, Amphissa versicolor Dall; b, A. columbiana Dall; e, A. undata Cpr.; d, Searlesia dira Reeve. All X3. Amphissa columbiana Dall Columbian Amphissa Figure sob Alaska to San Pedro, California. 1 inch in length, similar to versicolor, but characterized by its large size, numerous, weak, vertical, axial ribs (20 to 24 on the next to the last whorl, and missing on the last part of the last whorl), and by the low, rounded varix behind the outer lip. Color yellow-brown with indistinct mauve mottlings. Periostracum thin, yellowish brown. Moderately common in shallow water from Oregon to Alaska. Amphissa undata Carpenter Carpenter’s Amphissa Figure soc Monterey, California, to Lower California. ¥3 to % inch in length, similar to versicolor, especially in color, but with BUCCINIDAE 225 a much higher spire, stronger axial ribs, and much stronger, more acute, spiral cords. Moderately common from 25 to 265 fathoms. Amphissa bicolor Dall Two-tinted Amphissa Farralon Islands, to San Diego, California. ¥% to % inch in length, similar to versicolor, but thinner-shelled, usually with fewer ribs, glossy-white in color, but covered with a pale-straw peri- ostracum, and without the small teeth inside the outer lip. Dredged com- monly from 40 to 330 fathoms. Family BUCCINIDAE Genus Buccinum Linneé 1758 Buccinum undatum Linné Common Northern Buccinum Arctic Seas.to New Jersey. Europe. 2 to 4 inches in length, solid, chalky gray to yellowish with a moderately thick, gray periostracum. Axial ribs 9 to 18 per whorl, low, extending %4 to % way down the whorl. Spiral cords small, usually about 5 to 8 between sutures. Outer lip slightly or well sinuate and somewhat flaring. Aperture and parietal wall enamel-white. Anterior canal short. 1% nuclear whorls fairly large, smooth and translucent-white. Operculum oval, concentric, chitinous, and light yellow-brown. A very variable shell which sometimes lacks the axial ribs but may have numerous spiral threads. Common just off- shore to several fathoms in cold water. Buccinum tenue Gray Silky Buccinum Plate 24u Arctic Seas to Washington State. Arctic Seas to the Gulf of Maine. 1% to 2% inches in length; aperture 1% the length of the shell. Outer lip slightly sinuate, thin and slightly flaring. Axial ribs small, numerous, inter- twining and extending from suture to suture. Spiral sculpture of microscopic, beaded threads giving a silky appearance. Color light-brown. Common off- shore. Compare with plectrum Stimpson, Buccinum plectrum Stimpson Plectrum Buccinum Figure 51a Arctic Seas to Puget Sound. Arctic Seas to the Gulf of St. Lawrence. 2 to 3 inches in length; aperture a little more than % the entire length of the shell. Outer lip strongly sinuate, thickened and flaring. Axial ribs 226 American Seashells small (but larger and fewer than those in tenve), and limited to the upper fourth of the whorl. Spiral sculpture of numerous rough, but microscopic, incised lines. Color grayish white. Common offshore in cold water. Do not confuse with B. tenue. Buccinum glaciale Linné Glacial Buccinum Plate 24t Arctic Seas to Washington State. Arctic Seas to the Gulf of St. Law- rence. 2 to 3 inches in length, fairly thick-shelled, but light in comparison to its size. Characterized by its thick, flaring, turned-back outer lip, and by the 2 wavy, strong spiral cords on the periphery of the whorl. Spiral incised lines numerous. Color mauve-brown. Aperture cream with a purplish flush within. Common from low tide to several fathoms in the Arctic region. Buccinum baeri Middendorft Baer’s Buccinum Plate 24v Bering Sea. 1 to 2 inches in length, resembling a thin, beach-worn Thais lima. Aper- ture about % the length of the shell. Rather thin, smoothish, except for mi- croscopic, incised spiral lines. Color drab grayish with purplish to reddish undertones. Periostracum, when present, is thin, translucent and light-brown. Operculum ¥ the size of the aperture. Commonly found washed ashore on the beaches of Alaska and the Aleutians. A very unattractive shell. Genus Volutopsius Morch 1857 Subgenus Volutopsius s. str. Volutopsius castaneus Morch Chestnut Buccinum Figure 51c Alaska. 2% to 3% inches in length, rather solid; with 4 whorls; aperture large and slightly flaring. Interior brownish white enamel. Columella slightly arched, white within, brown on the parietal wall. Exterior surface brownish and smoothish, except for coarse axial wrinkles appearing more as deform- ities in growth. Moderately common on rocks below low-water mark. Subgenus Pyrulofusus Morch 1869 Volutopsius harpa Morch Left-handed Buccinum Plate 24p Alaska. BUCCINIDAE 227 3 to 4 inches in length, characteristically sinistral (left-handed), 4 whorls, with the smoothish nucleus indented. Sculpture of 6 to 12 very oblique, low, rounded axial ribs and numerous (often paired) raised spiral threads. Color ash-gray with a light brownish yellow periostracum. Interior of aperture tinted with tan. Operculum much smaller than the aperture. Dextral (right-handed) specimens are rarities. Fairly common in deep water. Genus Jumala Friele 1882 (Beringius Dall) Jumala crebricostata Dall Thick-ribbed Buccinum Figure 51b Alaska. 4 to 5 inches in length, moderately heavy, with 5 to 6 whorls. Charac- terized by the very strong, rounded spiral cords (3 to 4 between sutures) which on the base of the shell tend to be flat-topped. Periostracum grayish brown, thin and semi-glossy. A very handsome, but not commonly acquired species which occurs from 80 to 100 fathoms, Jumala kennicotti Dall Kennicott’s Buccinum Figure 51g Alaska. 5 to 6 inches in length, not very heavy. Characterized by about 9 strong, arched, somewhat rounded axial ribs extending from suture to suture, and, on the body whorl, extending *4 the way down the whorl. Spiral sculpture of microscopic scratches, except on the base where there are a dozen or so weak threads. Periostracum light-brown, thin, and usually flakes off in dried specimens. Shell chalky and whitish gray in color. Not uncommon in sev- eral fathoms of water; rarely in very shallow water, Genus Colus Roding 1798 Colus stimpsoni Morch Stimpson’s Colus Plate 23x Labrador to off North Carolina. 3 to 5 inches in length, fusiform, moderately strong, chalk-white in color, but covered with a semi-glossy, light- to dark-brown, moderately thin periostracum. Length of aperture about half the length of the entire shell. Sculpture of numerous incised spiral lines. Fairly common from 1 to 471 fathoms, 228 American Seashells Figure 51. Pacific Buccinums and Neptunes. a, Buccinum plectrum Stimpson; b, Jumala crebricostata Dall, ce, Volutopsius castaneus Morch; d, N eptunea eucosmtia Dall; e, Neptunea phoenicea Dall; £, Neptunea tabulata Baird; g, Jumala kennicotti Dall; h, Colus spitzbergensis Reeve, All reduced about yy. ———— BUCCINIDAE 229 Colus pubescens Verrill Hairy Colus Plate 23t Gulf of St. Lawrence to off North Carolina. 2 to 2% inches in length, very similar to stimpsomi, but the aperture is about % the entire length of the shell, the suture more abruptly impressed, the whorls slightly more convex and the siphonal canal usually, but not always, more twisted. Very commonly dredged from 18 to 640 fathoms, Colus pygmaea Gould Pygmy Colus Plate 23m Gulf of St. Lawrence to off North Carolina. Less than 1 inch in length, with 6 to 7 fairly convex whorls, fairly frag- ile, chalk-white, with spiral incised lines, and covered with a light olive-gray, thin, velvety periostracum. Aperture slightly more than % the length of the entire shell. Commonly dredged from 1 to 640 fathoms. Colus caelata Verrill and Smith (Massachusetts to North Carolina, deep water) is about the same size, but is characterized by about 12 strong axial ribs per whorl in addition to numerous fine spiral threads. It is chalky-white to gray. Colus spitzbergensis Reeve Spitzbergen Colus Figure 51h Bering Sea to Washington State. Arctic Seas to Gulf of St. Lawrence. 2% to 3 inches in length, rather light-shelled, and with 6 fairly well- rounded whorls. Spire long and of about 30 to 35 degrees. Siphonal canal short; columella almost straight. Outer lip flaring, slightly thickened. Sculp- ture of numerous (12 to 14 between sutures) low, flat-topped, small, equally sized spiral cords. Chalk-gray with a reddish to yellowish brown, thin peri- ostracum. Commonly dredged from 1 to 142 fathoms. Genus Neptunea Roding 1798 Neptunea decemcostata Say Brown-corded Neptune Plate 23s Nova Scotia to Massachusetts. 3 to 4% inches in length, rather heavy. Characterized by its grayish- white, rather smooth shell which bears 7 to 10 very strong, reddish-brown, spiral cords. The upper whorls show 2 to 3 cords. There is an additional band of brown just below the suture. A common cold-water species found offshore, but occasionally washed up on New England beaches. 230 American Seashells Neptunea ventricosa Gmelin Fat Neptune Plate 24s Arctic Ocean and Bering Sea. 3 to 4 inches in length, heavy, with a large, ventricose body whorl. Axial ribs or growth lines coarse and indistinct, rarely lamellate. Shoulders sometimes weakly nodulated. Spiral cords absent or very weak. Color a dirty-brownish white. Aperture white or flushed with brownish purple. Moderately common offshore. This is Chrysodomus satura Martyn and its several poor varieties. Neptunea pribiloffensis Dall Pribiloff Neptune Plate 24r Bering Sea to British Columbia. 4 to 5 inches in length, similar to N. /yrata, but with a lighter shell, with weaker and more numerous spiral cords, and with more numerous and stronger secondary spiral threads. Outer lip more flaring and the siphonal canal with more of a twist to the left. Fairly commonly dredged from 50 to 100 fathoms. Neptunea lyrata Gmelin Common Northwest Neptune Plate 24q Arctic Ocean to Puget Sound, Washington. 4 to 5 inches in length, % as wide, solid, fairly heavy. With 5 to 6 strongly convex whorls, bearing about 8 strong to poorly developed, raised spiral cords (2 of which usually show in each whorl in the spire). Faint, quite small, spiral threads are also present. Exterior dull whitish brown. Aperture enamel-white with a tan tint. Fairly common in Alaska from shore to 50 fathoms. This is Chrysodomus lirata Martyn. Subgenus Ancistrolepis Dall 1894 Neptunea eucosnia Dall Channeled Neptune Figure 51d Alaska to Oregon. 17% inches in length, solid, outer lip sharp, strong and crenulated. Si- phonal canal short, wide and slightly twisted. Spiral cords strong. Suture channeled. Shell chalk-white, but covered with a rather thick, yellow-brown to gray periostracum which is axially lamellate and bears minute, erect hairs. Aperture glossy-white. Not uncommonly dredged from 62 to 780 fathoms. N. californica Dall and bicincta Dall appear to be this species. —————— ——————————————— BUCCINIDAE Eyl Subgenus Szlcosipho Dall 1916 Neptunea tabulata Baird Tabled Neptune Figure sif British Columbia to San Diego, California. 3 to 4 inches in length, moderately solid, with 8 whorls, colored white with a thin brown periostracum. Characterized by the wide, flat channel next to the suture. It is bounded by a raised, scaly or fimbriated spiral cord. Remainder of whorl with numerous sandpapery spiral threads. A choice col- lector’s item, not uncommonly dredged from 30 to 200 fathoms. : Genus Kelletia Fischer 1884 Kclletia kelleti Forbes Kellet’s Whelk Plate 24w Santa Barbara, California, to San Quentin Bay, Mexico. 4 to 5 inches in length, characterized by its very heavy, white, fusiform shell, its fine, wavy suture, and by the sharp, crenulated outer lip. Whorls slightly concave between the suture and the shouldered periphery, which bears 10 strong, rounded knobs per whorl. Base with about 6 to ro incised, spiral lines. Aperture glossy and white. Very commonly caught in traps from ro to 35 fathoms. There are no other recent species in the genus. Often misspelled with two vs. Genus Bailya M. Smith 1944 Bailya intricata Dall Intricate Baily-shell Plate 25t Southern half of Florida. % inch in length, fairly strong, pure white in color and with cancellate sculpturing. Last whorl with 12 to 14 low axial ribs which are crossed by about a dozen spiral cords (between which there may be a much smaller thread). At their intersection there are small beads. Outer lip with a frilled, rounded varix. Columella smooth. Weak spiral cord present on inside of aperture on the upper parietal wall. Whorls slightly shouldered. No notch in lower part of outer lip. Nuclear whorl smooth, glassy and rounded. Un- common from 1 to 50 fathoms. Bailya parva C. B. Adams from the West Indies differs in not having its whorls shouldered, having weaker spiral cords, and in occasionally having brown coloring. Genus Antillophos Woodring 1928 Antillophos candei Orbigny Cande’s Phos Plate 25u North Carolina to south Florida and Cuba. 232 American Seashells 1 to 1% inches in length, slightly less than half as wide; strong, heavy and pure white. Last whorl with about 13 small spiral cords and about 24 stronger axial ribs. Where they cross, there are small, rounded beads. Outer lip near the low part has a shallow notch. Inside the lip are about a dozen prominent, spiral ridges. Columella with 2 low spiral ridges near the base, sometimes weaker ones above. Upper parietal wall with a strong spiral cord running back into the aperture. Nuclear whorls smooth, glossy, white and slightly carinate. Very commonly dredged from 20 to 100 fathoms. Genus Engina Gray 1839 Engina turbinella Kiener White-spotted Engina Plate 25w Lower Florida Keys and the West Indies. 43 to % inch in length, dark purple-brown with about 10 low, white knobs per whorl on the periphery. Base with 2 to 4 spiral rows of much smaller white knobs. Microscopic spiral threads numerous. Aperture thick- ened and constricted by 4 to 5 whitish teeth on the outer lip and by a twist of the columella just above the narrow siphonal canal. Do not confuse with Mitra sulcata which has several columellar plications. Common under rocks at low tide. Genus Searlesia Harmer 1916 Searlesia dira Reeve Dire Whelk Figure sod Alaska to Monterey, California. 1 to 1% inches in length, half as wide, with the brown aperture half the length of the dark gray, fusiform shell. Outer lip thin but strong and with fine serrations which extend back into the shell as small spiral threads. Colu- mella arched, chocolate-brown and glossy. Whorls in spire with 9 to 11 low, rounded axial ribs, and all of the exterior with numerous fine, unequal-sized spiral threads. Siphonal canal short and slightly twisted to the left. A com- mon shallow-water species commonly from northern California to the north. Genus Colubraria Schumacher 1817 Colubraria lanceolata Menke Arrow Dwarf Triton Plate 25x North Carolina to both sides of Florida and the West Indies. %4 to 1 inch in length, slender, with 7 whorls. Aperture long and nar- row. Varix strong and curled back. Parietal shield elevated into a collar. BUCCINIDAE 2333 Former distinct varices present every 73 of a whorl. Sculpture very finely cancellate and beaded. Nucleus brown, smooth and bulbous. Shell ash-gray with occasional orange-brown smudges. Uncommonly dredged on rocky bottom just offshore. Colubraria testacea Mérch from Tortugas and the West Indies is % to 1% inches in length, fatter, with numerous, small beads and with wider varices. C. swifti Tryon (subgenus Monostiolum Dall), also from the West Indies, is % inch long, without former varices, axially ribbed and heavily maculated with brown. Both are uncommon. Genus Pisania Bivona-Bernardi 1832 Pisania pusio Linné Miniature Triton Trumpet Plate 13-0 Southeast Florida and the West Indies. 1 to 1% inches in length, sturdy, smooth, and usually with a glossy finish. The outer lip is weakly toothed within, and the upper parietal wall has a small, white, swollen tooth near the top of the aperture. Color variable, but usually purplish brown with narrow spiral bands of irregular dark and light spots commonly chevron-shaped. Moderately common below low- water line in the region of coral reefs. Genus Cantharus Roding 1798 Subgenus Pollia Sowerby 1834 Cantharus tinctus Conrad Tinted Cantharus Plate 25y North Carolina to both sides of Florida and the West Indies. 34 to 1/4 inches in length, heavy, spire evenly conic; aperture with a small canal at the top. Axial ribs low and weak. Spiral cords numerous and weak, forming weak beads as they cross the ribs. Inside of outer lip with small teeth which are strongest near the top. Color of shell variegated with yellow-brown, blue-gray and milky-white. Fairly common in shallow water. The young are easily confused with Thais. See remarks under T. rustica, p. 214. Cantharus auritula Link Gaudy Cantharus Southeast Florida and the West Indies. Similar to C. tinctus, but broader, with shouldered whorls, with about 9 stronger axial ribs per whorl and with about 1o sharp spiral threads on 234 American Seashells the last whorl. Outer lip turned in as the varix is formed. Color brighter. Posterior canal longer. Common in the West Indies; intertidal. Cantharus cancellarius Conrad Cancellate Cantharus West coast of Florida to Texas and Yucatan. Similar to C. tinctus, but with a lighter shell, higher spire, and with sharp, spiral threads and narrow, axial ribs which cross to make a beaded and can- cellate sculpturing. Posterior siphonal canal absent or weak. Varix very weak. Moderately common in shallow water. Genus Macron H. and A. Adams 1853 Macron lividus A. Adams Livid Macron Plate 24x Monterey, California, to Lower California. %4 to 1 inch in length, half as wide, strong, with 5 whorls which are covered with a thick, felt-like, dark-brown periostracum. Shell yellowish to bluish white. Outer lip sharp, strong, and near its base bearing a small, spiral thread. Columella strongly concave and white. Upper end of aperture narrow, with a small, short channel and with a white, tooth-like callus on the parietal wall. Siphonal canal short and slightly twisted. Base of shell with a half dozen incised spiral lines. Operculum chitinous, brown, thick, oval and with the nucleus at one end. Very common under stones at low tide. Family MELONGENIDAE Genus Melongena Schumacher 1817 (Galeodes) Melongena corona Gmelin Common Crown Conch Figure 52 Florida, the Gulf States and Mexico. 2 to 4 inches in length, very variable in size, color, shape and production of spines. Dirty-cream with wide, spiral bands of brown, purplish brown or dark bluish black. Pure white “albinos” are infrequent. Shoulder and base of shell with 1, 2, 3 or 4 rows of semi-tubular spines which may point upward or horizontally. Numerous varieties have been named which do not even warrant subspecific standing: minor Sowerby (dwarf); estepho- menos Melville (dwarf and narrow), altispira Pilsbry and Vanatta (long and narrow); bispinosa Philippi (2 rows of spines); ispinata Richards spineless shoulder); and artiniana Philippi. A very common species in Florida. Used extensively in the shellcraft industry. MELONGENIDAE 235 Melongena corona perspinosa Pilsbry and Vanatta appears to be a good subspecies. (Tampa south to Lossmans Key, Florida). Up to 4% inches in length, heavier and wider than corona, with a wider aperture, and with shoulder spines standing out at right angles, and with 2 or 3 rows of smaller spines below the larger ones. A descendant possibly of the Pliocene subspecies swbcoronata Heilprin. Soft parts and radula described and figured in Frank Lyman’s excellent Shell Notes, vol. 2, no. 2-3, 1948 (published privately by Lyman, Lantana, Florida). Figure 52. Two forms of the Crown Conch, Melongena corona Gmelin, from Florida. a, sandy area; b and ec, from oyster bed. Reduced 14. Melongena melongena Linné West Indian Crown Conch Plate 23h Florida Keys (?) and the West Indies. 3 to 6 inches in length, similar to corona, but heavier, with rounded shoulders; smaller, more solid spines, and with a distinct channel at the suture. Common in the Greater Antilles. Genus Busycon Roding 1798 (Fulgur Montfort) Busycon carica Gmelin Knobbed Whelk Plate 231 South shore of Cape Cod to central east Florida. Adults 5 to 9 inches in length; characterized by having low tubercles on the shoulder of the whorl and in being right-handed. Aperture light orange-yellow, but sometimes brick-red. The young show axial streaks of brownish purple. Common in shallow water. 236 American Seashells Busycon contrarium Conrad Lightning Whelk Plate 23-0 South Carolina to Florida and the Gulf States. 4 to 16 inches in length, left-handed, with a row of moderately small, triangular knobs at the shoulder. Color grayish white with long, axial, wavy streaks of purplish brown which are blurred along their posterior edge. Albino shells are rare. Off Yucatan and rarely in Florida, right-handed specimens are found. Their siphonal canal is longer than that in B. carica, and the shell is lighter than that of perversum. A very common species in west Florida. Busycon perversum Linné Perverse Whelk Plate 23k Both sides of central Florida. 4 to 8 inches in length, very heavy and with a glossy finish. This species should not be confused with the common contrarium. This species can be either left-handed (formerly known as kieneri Philippi 1848) or right-handed (formerly known as eliceans Montfort 1810, pl. 23k). The name B. perversum or Fulgur perversa in most old popular books refers to B. contrarium. he perverse whelk is an uncommon species. It is characterized by the heavy, polished shell and the swollen, rounded ridge around the middle of the whorl. Dredged from 4 to 10 fathoms. Subgenus Busycotypus Wenz 1943 Busycon canaliculatum Linné Channeled Whelk Plate 23n Cape Cod to St. Augustine, Florida. 5 to 7% inches in length, characterized by a deep, rather wide channel running along the suture and by the heavy, felt-like, gray periostracum. Com- mon in shallow, sandy areas. Left-handed specimens are rare. The subgenera Fulguropsis FE. S. Marks 1950 and Sycofulgur Marks 1950 are the same as Wenz’s subgenus. Busycon spiratum Lamarck Pear Whelk Plate 9g North Carolina to Florida and the Gulf States. 3 to 4 inches in length; characterized by its smooth, rounded shoulders and the deep, but narrow channel at the suture. Periostracum thin and velvety. Do not confuse with Ficus which is a much more fragile shell. Common in shallow, sandy, clear water areas. The animal is cream-gray. Known in all previous popular books as B. pyrum Dillwyn. In the western NASSARIIDAE 23 part of the Gulf of Mexico, specimens often have a weak keel on the shoulder (form or subspecies plagosum Conrad). Busycon coarctatum Sowerby Turnip Whelk Plate 1a Yucatan area, Mexico. Until 1950 this was considered a very rare species, but dredging activities of shrimp trawlers have brought a large number of them to light. Charac- terized by its turnip-like shape, single row of numerous small, dark-brown spines, and by its golden-yellow aperture. 5 inches in length. Family NASSARIIDAE Genus Nassarius Dumeril 1806 Subgenus Nassarius s. str. Nassarius vibex Say Common Fastern Nassa . Plate 23q Cape Cod to Florida, the Gulf States and the West Indies. % inch in length, heavy, with a well-developed parietal shield. Last whorl with about a dozen, poorly developed, axial ribs which are coarsely beaded. Color gray-brown to whitish with a few splotches or broken bands of subdued, darker brown. A common sand or mud-flat species. Some specimens have numerous weak spiral cords. Parietal shield sometimes yellow- ish. Nassarius acutus Say Sharp-knobbed Nassa Figure 53c West coast of Florida to Texas. Y% inch in length, characterized by its glossy shell, its strong, pointed Ws Bey She §> pom beads, and in occasionally having a narrow, brown, spiral thread connecting the beads. Moderately common. Fossil specimens are twice as large. Nassarius insculptus Carpenter Smooth Western Nassa Figure 53f Point Arena, California, to Lower California. %4 inch in length, outer lip thickened, parietal wall thick, white but not very wide. Body whorl smoothish, except for weak, fine spiral threads. Axial ribs numerous only on early whorls. Color white, covered by a yellow- ish white periostracum. Moderately common; dredged from 20 to 200 fathoms. 238 American Seashells Nassarius tegula Reeve Western Mud Nassa Plate zon San Francisco to Lower California. BY *%4 inch in length, moderately heavy, with a heavy, whitish or brown- stained parietal callus. Body w horl smoothish around the middle, but with a spiral row of fairly large nodes below the suture. In the spire, the nodes are usually divided in two. Base of body whorl with a few weak, spiral threads. Outer lip thick. Color olive-gray to brownish, often with a narrow, whitish or purplish, spiral band. A common mud-flat species. at —o : Meet y ee “ a TL) rete} \ ry meme fy “tae et FiGurE 53. Nassa Mud Snails. ATLANTIC: a, Nassarius ambiguus Pulteney; b, N. ambiguus form consensus Rav.; ce, N. acutus Say. PACIFIC: dic. mendicus Gould; e, N. perpinguwis Hinds; f, N. insculptus Cpr. All-Xe: NASSARIIDAE 239 Subgenus Himia Gray 1847 Nassarius ambiguus Pulteney 1799 Variable Nassa Plate 23r; figure 53a North Carolina to Florida and the West Indies. ¥ inch in length, relatively light-shelled, usually pure white in color, but occasionally with 1 or 2 narrow, spiral bands of light yellowish brown. Number of strong, axial ribs per whorl varies from 8 to 12. Upper part of whorl sometimes shouldered. Numerous spiral, rounded cords are strong or weak. Parietal shield enamel-white, usually not well-developed. N. con- sensus Ravenel is possibly only a form of this unusually variable species (fig. 53b). Nassarius trivittatus Say New England Nassa Plate 23] Nova Scotia to South Carolina. %4 inch in length, rather light-shelled, 8 to g whorls; nuclear whorls smooth. Whorls in spire with 4 to 5 rows of strong, distinct beads. Parietal wall thinly glazed with white enamel. Outer lip sharp and thin. Whorls slightly channeled just below the suture. Color light-ash to yellowish gray. Common from shallow water to 45 fathoms. Nassarius perpinguis Hinds Western Fat Nassa Figure 53e Puget Sound to Lower California. %4 to 1 inch in length, fairly thin, with a rather fragile outer lip. Similar to N. californianus, but with much finer sculpture (usually finely cancellate or minutely beaded), and yellowish white in color with 2 or 3 narrow, spiral bands of orange-brown, one of which borders the suture. The sculpture is variable with spiral threads often predominant. Very abundant along most of the coast. Intertidal flats to 50 fathoms. Nassarius californianus Conrad Californian Nassa Squaw Creek, Oregon, to Lower California. 1 inch in length, without a thick parietal shield and the outer lip not thickened. Shell with numerous, rather coarse beads arranged in 20 to 30 axial, slanting ribs. 11 to 12 spiral threads on the last whorl; 5 to 7 on the whorls above. Color white with an ashy or yellow-gray periostracum. Moderately common just offshore to 35 fathoms. Compare with perpinguis. 240 American Seashells Nassarius mendicus Gould Western Lean Nassa Figure 53d Alaska to Lower California. aan: 72 to % inch in length, with a moderately high spire. Outer lip not thickened. Sculpture consists of numerous, small beads which are formed by the crossing of about a dozen small axial ribs and smaller spiral threads. Color yellowish gray. Common in shallow water in the north. The subspecies or form cooperi Forbes has weaker spiral threads and about 7 to g strong, whitish, smoother axial ribs which persist to the last of the body whorl. Color grayish yellow to whitish, often with fine, spiral, brown or mauve lines. Very common in the south. Subgenus Zaphon H. and A. Adams 1853 Nassarius fossatus Gould ° Giant Western Nassa Plate 20s Vancouver Island to Lower California. 17% to 2 inches in length, orange-brown to brownish white in color. Early whorls coarsely beaded; last whorl with about a dozen coarse, variously sized, flat-topped spiral threads and with about a dozen short axial ribs on the top third of the last whorl. Outer lip with a jagged edge and constricted at the top. The largest and one of the common intertidal Nassa snails on the Pacific coast. Subgenus //]yanassa Stimpson 1865 Nassarius obsoletus Say Eastern Mud Nassa Plate 23p Gulf of St. Lawrence to northeast Florida. Introduced to the Pacific coast. %4 to 1 inch in length, usually covered with mud and algae, and has its spire eroded at the tip. Color dark black-brown. Sculpture of numerous rows of weak beads. Parietal wall thickly glazed with brown and gray. Columella with a single, strong spiral ridge near the base. Outer lip with half a dozen small grayish teeth which run back into the aperture. Very common on oozy, warm mud flats. Family FASCIOLARIIDAE Subfamily FASCIOLARIIN AE Genus Leucozonia Gray 1847 Leucozonia nassa Gmelin Chestnut Latirus Plate 11d Florida to Texas and the West Indies. FASCIOLARIIDAE 241 1% inches in length, heavy, squat, with its whorls shouldered by about 9 large nodules. Characterized by its semi-glossy, chestnut-brown color with a faint, narrow spiral band of whitish at the base of the shell which terminates into a small, distinct spine on the outer lip. Columella with 4 weak folds at the base. Aperture yellowish tan within. Common among rocks at low tide. Alias L. cingulifera Lamarck. Leucozonia ocellata Gmelin White-spotted Latirus Plate r1e West coast of Florida and the West Indies. 1 inch in length, % as wide, squat and heavy. Color dark-brown to blackish with a row of about 8 large, white, rounded nodules at the periphery and about 3 or 4 spiral rows of smaller white squares on the base of the shell. Base of columella with 3 small folds. Apex usually worn white. A common intertidal species found under rocks. Genus Latirus Montfort 1810 Latirus mcgintyi Pilsbry McGinty’s Latirus Plate 11b Southeast Florida. ¥, to 2% inches in length, elongate, heavy, and with about ro whorls. Color cream with a solid yellow-brown periostracum. Aperture bright yellow. Umbilicus variable, but usually funnel-shaped. Each whorl with 8 low, rounded ribs which are noduled by 2 spiral cords in the upper whorls and 4 cords on the wide periphery of the last whorl. Numerous fine spiral threads present. Lower columella with 2 weak folds. Uncommon. Latirus infundibulum Gmelin Brown-lined Latirus . Plate 11a Florida Keys and the West Indies. 3 inches in length, heavy, resembling a Fusinus in shape, but character- ized by the 3 weak folds on the columella, the light-tan to light-brown shell which bears small, darker brown, wavy, glossy, smooth spiral cords. 7 to 8 strong axial nodules per whorl. Umbilicus imperfect, sometimes funnel- shaped. Moderately common in the West Indies, rare in Florida. Latirus brevicaudatus Reeve Short-tailed Latirus Plate rif Lower Florida Keys and the West Indies. 1 to 2% inches in length, rather broad, with a short siphonal canal, with 8 to 9 rounded, long axial ribs crossed by numerous spiral threads. Color 242 American Seashells light-chestnut, reddish brown or dark-brown. Not so shouldered as, and less coarsely sculptured than, me gintyi. It is much stouter and not so elongate as infundibulum, but like that species may have narrow, brown spiral lines or threads. Moderately common in the West Indies. Genus Fasciolaria Lamarck 1799 Fasciolaria tulipa Linné True Tulip Plate 13b North Carolina to south half of Florida and West Indies. 3 to 5 inches in length, with 2 or 3 small spiral grooves just below the suture, between which the shell surface is often crinkled. Sometimes with broken spiral color lines. A beautiful orange-red color variety is not un- common on the Lower Keys. Common. Giants reach a Jength of 10 inches. Fasciolaria hunteria Perr Banded Tuli y p Plate 13c North Carolina to Florida and the Gulf States. 2 to 4 inches in length, whorls entirely smooth near the suture. The widely spaced, rarely broken, distinct, spiral, purple-brown lines are charac- teristic. Albino shells are rare. A common western Florida species which lives in warm, shallow areas. Formerly F. distans Lamarck, a later name. The subspecies branhamae Rehder and Abbott from Yucatan to off west Texas has a much longer siphonal canal and the spiral color lines are also on the siphonal canal. Intergrades exist in Louisiana and Alabama. Branham’s Tulip is moderately common. Genus Pleuroploca P. Fischer 1884 Pleuroploca gigantea Kiener Florida Horse Conch Platesea North Carolina to both sides of Florida. Almost 2 feet in length, although usually about 1 foot. Outer surface dirty-white to chalky-salmon, and covered with a fairly thick, black-brown periostracum which flakes off in dried specimens. The young (up to about 3% inches) have a thinner periostracum and the entire shell is a bright orange- red. A form which lacks the nodules on the last whorl was named reevei Philippi 1851. P. papillosa Sowerby 1825 is insufficiently described to apply with any certainty to this species. A similar, large species, P. princeps Sowerby (the Panama Horse Conch), occurs from the Gulf of California to Ecuador. Its operculum has deep, rounded grooves. Both of these Horse Conchs were previously put in the genus Fasciolaria. FASCIOLARIIDAE 243 Subfamily FUSININAE Genus Fusinus Rafinesque 1815 Fusinus timessus Dall Turnip Spindle Plate 11g Gulf of Mexico. About 3 inches in length, solid, pure white, with a thin, gray periostra- cum. Aperture round with a flaring, raised parietal wall which, like the inside of the outer lip, is enamel-white and bears numerous spiral threads. Each whorl with 10 to 12 low, short axial ribs at the periphery. Upper whorls with 8 to 9 small, but sharp and slightly wavy, smooth spiral cords. Last whorl and the long siphonal canal with a total of about 30 to 40 small cords between which is often a very fine one. Dredged uncommonly from 20 to 50 fathoms. Fusinus eucosmius Dall Ornamented Spindle Plate ric; figure 22k Gulf of Mexico. 3 inches in length, with about 12 rounded whorls and with a small, roundish aperture located at the middle of the shell. Siphonal canal long, its diameter about equal to that of the aperture. Whorls with 8 large, rounded axial ribs which in the upper whorls are crossed by about 6 strong, sharp, slightly wavy spiral threads. Apex often leaning to one side. Color all white with a rather heavy, grayish-white to yellowish periostracum. Rather com- monly dredged offshore, but still a collector’s item. Subgenus Barbarofusus Grabau and Shimer 1909 Fusinus harfordi Stearns Harford’s Spindle Figure 54a Mendocino County, California. 2 inches in length, heavy, exterior dark, orange-brown, with 11 to 12 wide, rounded axial ribs crossed by small, sharply raised, finely scaled spiral cords. Rare in moderately deep water. Fusinus kobelti Dall Kobelt’s Spindle Figure 54b Monterey to Catalina Island, California. 2% inches in length, heavy, similar to harfordi, but with a longer siphonal canal, fewer and larger axial ribs (8 to 10 per whorl), colored white, except for several orange-brown spiral cords. Periostracum rather thick, opaque and light-brown. The spiral cords in harfordi are much larger and with squarish tops. Moderately common in shallow water to 35 fathoms. 244 American Seashells Sg Figure 54. Californian Spindles. a, Fusinus harfordi Stearns, 2 inches; b, F. kobelti Dall, 24% inches; ce, Aptyxis luteopicta Dall, %4 inch. Fusinus barbarensis Yrask Santa Barbara Spindle Plate 24z Oregon to San Diego, California. 4 to 5 inches in length, almost 4 as wide, 9 to 10 rounded whorls, the early ones with about 10 low, axial ribs which are very weak or absent in the last 2 whorls. Spiral threads prominent and numerous. Color dirty gray- white, sometimes with a pinkish or yellowish cast. Dredged from 50 to 200 fathoms, and occasionally brought up in fishermen’s nets. Genus Aptyxis Troschel 1868 Aptyxis luteopicta Dall Painted Spindle Figure 54c Monterey, California, to Lower California. %4 inch in length, strong, with a thin outer lip. Color dark purplish brown with an indistinct, wide, spiral band of cream at the periphery. Common from low tide to 20 fathoms. Family XANCIDAE Subfamily XANCINAE Genus Xancus Roding 1798 Xancus angulatus Solander West Indian Chank The Bahamas, Key West, Cuba, Yucatan and Bermuda. OLIVIDAE 245 7 to 14 inches in length, very heavy. Color cream-white with a thick, light-brown periostracum. Interior often tinged with glossy, pinkish cream or deep, brownish orange. Columella bears 3 strong, widely spaced folds. Middle of whorl on inside of aperture often with a spiral, weak ridge. A left- handed specimen of this species would be worth its weight in silver. Once called Turbinella scolyma Gmelin. Common in the Bahamas and Cuba. Subfamily VASINAE Genus Vasum Roding 1798 Vasum muricatum Born Caribbean Vase Plate 23] South half of Florida and the West Indies. 2% to 4 inches in length, heavy. Blunt spines are at the shoulder and near the base. Shell chalk-white, covered by thick, black-brown periostra- cum. Aperture glossy-white and with a purplish tinge. Columella with 5 strong folds, the first and third being the largest. Rather common, often in pairs, in shallow water. Preys on worms and clams. The subspecies coestus Broderip 1833 (Panamanian Vase) occurs from the Gulf of California to Panama, and differs only in having 4 (rarely 5) columella folds and in having heavier spiral cords. It is common. Superfamily VOLUTACEA Family OLIVIDAE Genus Oliva Bruguiére 1789 Oliva sayana Ravenel Lettered Olive Plate 12a North Carolina to Florida and the Gulf States. 2 to 2% inches in length, moderately elongate, with a glossy finish and with rather flat sides. Color grayish tan with numerous purplish brown and chocolate-brown, tent-like markings. A common species found at night crawling in sand in shallow water. Formerly called O. Jitterata Lamarck. Do not confuse with O. reticularis which is generally smaller, which has a much more shallow canal at the suture, whose apical whorls are slightly con- vex instead of slightly concave, and whose sides of the whorls are more convex. Dead specimens buried for a long time in bay mud may take on an artificial black coloration. Oliva reticularis Lamarck Netted Olive Plate 12c Southeast Florida and the West Indies. 246 American Seashells 1% to 1% inches in length, similar to sayana, but smaller, more globose, with an oily finish and generally more lightly colored. The Golden Olive or Golden Panama is merely a rare orange form of this species. Sometimes pure white or very dark-brown in color. A common West Indian species. See remarks under sayana. Genus Olivella Swainson 1831 Distinguished from the genus Oliva by its much smaller shell and in pos- sessing an operculum. Olivella mutica Say Variable Dwarf Olive Plate 22v North Carolina to Florida, Texas and the West Indies. % to % inch in length, half as wide, with a sharp apex. Strong, glossy callus is present on the parietal wall at the upper end of the aperture. Varia- ble in color: ashy grays and chocolate-browns to yellowish or whitish with wide bluish-gray spiral bands. Sometimes brightly banded with white and browns. A very common species found in warm, shallow waters. Olivella nivea Gmelin West Indian Dwarf Olive Plate rth, j Southeast Florida, the West Indies and Bermuda. % to 1 inch in length, whorls about 7, apex sharply pointed; nucleus small, white, tan or purple. Suture channel is deep and fairly wide; with a strongly concave, etched, spiral indentation on the side of the preceding whorl. Color variable, usually cream-white with orange, tan or purple occur- ring in clumps in a spiral series just below the suture and just above the fasciole (that raised spiral ridge at the base of the shell). Fasciole lacks color. Common from shore to 25 fathoms. Compare with jaspidea which has a more bulbous apex. Olivella jaspidea Gmelin Jasper Dwarf Olive Plate 11-1 Southeast Florida to Barbados. % to % inch in length, whorls about 5, apex blunt, nuclear whorls large. Color variable, usually grayish white with small, dull maculations of purplish brown. Fasciole at base of columella with irregular, brown spots and bars. A common West Indian species found in shallow water in sand. Compare with nivea. Olivella moorei Abbott Moore’s Dwarf Olive Off Key Largo to Key West, Florida. OLIVIDAE 247 % inch in length, apex bulbous. Characterized by its translucent shell with numerous, long, wavy, axial flammules of reddish brown on the sides of the whorls. Dredged from 115 to 144 fathoms. Named for Hilary B. Moore of the University of Miami, Florida. Olivella floralia Duclos Common Rice Olive North Carolina to both sides of Florida and the West Indies. 3 to % inch in length, slender, fusiform and with a sharp apex. Color all white, but often with a dull bluish undertone. Apex white, orange or dull purplish. Columella with numerous, very small folds. Common in shal- low water. Olivella baetica Carpenter Beatic Dwarf Olive Plate 20g Kodiak Island, Alaska, to Lower California. % to %4 inch in length, moderately elongate, rather light-shelled, glossy, and colored a drab-tan with weak purplish brown maculations often arranged in axial flammules which may be more pronounced near the suture. Columellar callus weakly developed, the lower end with a double-ridged spiral fold. Fasciole white, often stained with brown. Early whorls usually purplish blue. O. porteri Dall is the same. Olivella pedroana Conrad San Pedro Dwarf Olive Oregon to Lower California. %@ to % inch in length, resembling O. baetica, but much heavier, much stouter, with a heavy callus, and colored light-buff to clouded, brownish gray with long, distinct, axial, zigzag stripes of darker brown. Fasciole and callus always white. The lowest columellar spiral ridge is single or rarely double. Moderately common from 1 to 15 fathoms. O. pycna Berry is the same, and matches the neotype designated by Woodring in 1946. O. intorta Carpenter is also this species. Subgenus Callianax H. and A. Adams 1853 Olivella biplicata. Sowerby Purple Dwarf Olive Plate 121 Vancouver Island to Lower California. 1 to 1% inches in length, globular to elongate, quite heavy. Upper colu- mella wall with a heavy, low, white callus. Lower end of columella with a 248 American Seashells raised, spiral fold which is cut by 1, 2, or 3 spiral, incised lines. Color varia- ble, but usually bluish gray or whitish brown with violet stains around the fasciole and lower part of the aperture. Brown and pure-white specimens are sometimes found. Abundant in summer months in sandy bays and beaches. Sometimes dredged down to 25 fathoms on gravel bottom. Family MITRIDAE Genus Mitra Lamarck 1799 Mitra florida Gould Royal Florida Miter Plate 131 South half of Florida and the West Indies. 1% to 2 inches in length, with about 6 whorls. Characterized by its smooth, white, glossy whorls which bear on the last one about 16 spiral rows of evenly spaced, small, roundish dots of orange-brown. There are also odd patches of light orange-brown. 9 columella folds, the lower 7 being very weak. An uncommon species considered a choice collector’s item. Formerly known as M. fergusoni Sowerby. Mitra swainsoni antillensis Dall Antillean Miter North Carolina to Florida and the West Indies. 3 inches in length, about % as wide, with the aperture half as long as the entire shell. 10 whorls smooth, except for 5 or 6 weak spiral threads on the upper fourth of the whorl. Columella with 4 slanting, spiral folds, the largest being the uppermost. Color grayish white with a light-brown to olive periostracum. Short siphonal canal slightly recurved. Rare. Mitra nodulosa Gmelin Beaded Miter Plate 26b North Carolina to Florida and the West Indies. 4 to 1 inch in length, solid, glossy, orange to brownish orange in color, and with about 17 long, axial riblets which are rather neatly beaded. Suture deep, with the whorls slightly shouldered. Columella folds 3, large and white. A common species frequently washed ashore or found under rocks at low tide. Mitra styria Dall Dwarf Deepsea Miter Lower Florida Keys and the West Indies. ¥% inch in length, fusiform in shape, moderately fragile and ashen-white MITRIDAE 249 in color. 10 whorls. Characterized by the numerous, very small, beaded, axial riblets and the thin, gray periostracum. Columella folds 5, the lower 2 being very weak. Nuclear whorls small, smooth and pointed. Commonly dredged from 30 to 333 fathoms. Mitra barbadensis Gmelin Barbados Miter Plate 26d Southeast Florida and the West Indies. 1 to 1% inches in length, slender, with the aperture wide below and half the length of the entire shell. Characterized by its yellow-brown to fawn color which has an occasional fleck of grayish white. Aperture tan within. Columella with 5 slanting folds. The sides of the spire are almost flat. Weak spiral threads are often present especially in the earlier whorls. A common species under rocks at low tide. Mitra hendersoni Rehder Henderson’s Miter Plate 26c Southeast Florida and the West Indies. ¥% to %4 inch in length, fusiform in shape, with 8 whorls, each bearing a dozen sharp axial ribs which extend halfway down the whorl. Numerous microscopic, spiral cords present. Columella with 4 folds. Color drab pink- ish gray with the upper half of the whorl bearing a wide, lighter, spiral band. Moderately common offshore in several fathoms. Mitra sulcata Gmelin Sulcate Miter Plate 26a Southeast Florida and the West Indies. ¥% inch in length, rather fusiform in shape, with axial ribs as in bender- soni, but without spiral threads. 4 columella folds large and dark-brown. Color of shell dark chocolate-brown with a narrow, white, spiral band on the upper half of the whorl. Moderately common below low-water line under rocks in sand. Do not confuse with Engina turbinella which has no columella folds. Mitra albocincta C, B, Adams is probably this species, Mitra idae Melville Ida’s Miter Plate 2o0p Farallon Islands to San Diego, California. 2 to 3 inches in length, heavy, elongate. With 3 columella folds. Color mauve-brown, but usually covered with a thick, finely striate, black perio- stracum. Uncommon offshore. 250 American Seashells Family VOLUTIDAE Subfamily VOLUTINAE Genus Voluta Linneé 1758 Voluta musica Linné Common Music Volute Plate 13g Caribbean area. 2 to 2% inches in length, heavy and with a polished finish. 3 nuclear whorls bulbous and yellowish. 3 postnuclear whorls plicate at the shoulder. Columella with about 9 evenly spaced folds. Characterized by the pinkish cream background and 2 to 3 spiral bands of fine lines which are dotted with darker brown (the musical notes). A moderately common West Indian species not found in the United States, but a favorite with collectors. A num- ber of useless names have been applied to the numerous variations of this species. This is one of the few volutes to have an operculum. Voluta virescens Solander Green Music Volute Lower Florida Keys (rare) and the Caribbean. 2 inches in length, moderately heavy with the aperture % the total length of the shell. Whorls flat-sided and with weak, axial nodules high on the shoulder. Numerous spiral, incised lines and fine threads present. Colu- mella with about a dozen folds of variable sizes. Exterior dull greenish brown with weak, narrow, spiral bands of lighter color dotted with black-brown. Aperture pale cream to gray within. A rare species in southeast Florida, but not uncommon along the northern coast of South America. Subfamily SCAPHELLINAE Genus Scaphella Swainson 1832 Scaphella junonia Shaw The Junonia Plate 13f North Carolina to both sides of Florida to Texas. 5 to 6 inches in length, rather solid and smooth. 4 folds on the colu- mella. Characterized by the cream background and the spiral rows of small reddish brown dots. Moderately common from 1 to 30 fathoms, but rarely washed ashore. A golden form occurs off Alabama (subspecies johnstoneae Clench 1953) and specimens from Yucatan have a white background with smaller spots (subspecies butleri Clench 1953). About 50 specimens a year are found on west Florida beaches, and many more are brought in by fisher- men. VOLUTIDAE 251 Subgenus Aurinia H. and A. Adams 1853 Scaphella dohrni Sowerby Dohrn’s Volute Plate. 13] Off the south half of Florida. 3 to 4 inches in length, similar to jwnonia, but much lighter in weight, much more slender, with a higher spire and with numerous exceedingly fine, incised (cut) spiral lines. Some specimens have the early whorls slightly angled and with short axial ribs. This is the form named florida Clench and Aguayo and is probably not a good species. A rare species which is appear- ing in private collections more and more. Scaphella dubia Broderip Dubious Volute Off south half of Florida and the Gulf of Mexico. 4 inches in length, similar to dobrni, but more slender, with fewer spots, and with 6 to 7, instead of 9 to 10, rows of spots. A rare and exquisite spe- cies from moderately deep water. Scaphella schmutti Bartsch Schmitt’s Volute Plate 13e Off Tortugas, Florida. 5 inches in length. Under the brownish periostracum the shell is chalky, pale salmon and with 4 or 5 spiral rows of weak, brown, square spots. A thick, yellowish-gray glaze overlays the periostracum on the parietal side of the body whorl. Columella straight, while in R. georgiana Clench from Georgia to east Florida it is arched. Both quite rare, the former in 80 fathoms of water. The genus Rehderia Clench 1946 was unfortunately erected upon an ecological or pathological character and should be considered a synonym of Scaphella. Genus Arctomelon Dall 1915 (Boreomelon Dall 1918) Arctomelon stearnsi Dall Stearns’ Volute Alaska. 4 to 5 inches in length, strong; exterior chalky-gray with mauve-brown undertones. Aperture semi-glossy, light-brown. Columella brownish with 2 moderately large folds and a weak one below. Nucleus bulbous, chalky- white. Uncommon offshore down to roo fathoms. 252 American Seashells Family CANCELLARIIDAE Genus Cancellaria Lamarck 1799 Cancellaria reticulata Linné Common Nutmeg Plate 13k North Carolina to both sides of Florida. 1 to 1% inches in length, strong, with numerous spiral rows of small, poorly shaped beads which, with the weak axial and spiral threads, give a reticulate appearance. Columella with 2 folds, the uppermost being very strong and furrowed by 1 or 2 smaller ridges. Color cream to gray with heavy, broken bands and maculations of dark orange-brown. Rarely all white. Common in shallow water to several fathoms. C. conradiana Dall is probably only a form of this species. The subspecies adelae Pilsbry from the Lower Florida Keys is smooth- ish, except for incised lines on the body whorl. The aperture is faintly flushed with pink, Uncommon. (Adele’s Nutmeg). Figure 55. Cancellarid Shells. a, Admete couthouyi Jay (Atlantic and Pacific, 34 inch); b, Cancellaria crawfordiana Dall (California; 14%4 inches); c, Narona cooperi Gabb (California; 2 inches); d, Trigonostoma tenerum Philippi (Florida, 3) j 14. inch). Subgenus Massyla H. and A. Adams 1854 Cancellaria crawfordiana Dall Crawford’s Nutmeg Figure 55b Bodega to San Diego, California. 1 to 2 inches in length, heavy, white in color, but covered with a thick, rather fuzzy, gray-brown periostracum. Aperture enamel-white. Uncom- mon from 16 to 204 fathoms. CANCELLARIIDAE 253 Genus Narona H. and A. Adams 1854 Subgenus Progabbia Dall 1918 Narona cooperi Gabb Cooper’s Nutmeg Plate 24y; figure 55c Monterey, California, to Lower California. 2 to 24% inches in length, moderately heavy; columella with 2 small spiral folds. Whorls slightly shouldered, with about a dozen to 15 narrow axial ribs which at the top bear a single, low, sharp knob. Color brownish cream with a dozen or so narrow, brown spiral bands. Aperture orange- cream. Outer lip sometimes with numerous white, glossy, spiral cords on the inside. An uncommon, deep-water species, occasionally brought up in fish nets. Said to grow to 7 inches in length. Genus Trigonostoma Blainville 1827 Trigonostoma tenerum Philippi Philippi’s Nutmeg Figure 55d Southern half of Florida. %4 inch in length, fairly thin, but a quite strong shell. 4 whorls, strongly shouldered with the upper part of the whorl smooth and flat, and the sides with 3 to 5 spiral rows of strong nodules or blunt beads. Umbilicus very deep and funnel-shaped. Color light orangish brown. Uncommon just off- shore. Trigonostoma rugosum Lamarck (in the subgenus Bivetiella Wenz 1943) is similar, but heavier, whitish with brownish maculations, without an umbili- cus, and with about 8 strong axial ribs crossed by spiral threads. Known as the Rough Nutmeg. It is rare in most areas of the West Indies, and has not been reported from the United States. Genus Admete Kroyer 1842 Admete couthouyi Ja Common Northern Admete y y Figure 55a Arctic Seas to Massachusetts. Arctic Seas to San Diego, California. % to %4 inch in length, moderately thick, with 6 whorls. Suture wavy, well-impressed. Sculpture coarsely reticulate, often beaded or with the axial cords the strongest. Columella strongly arched and bearing 2 to 5 very weak, spiral folds near the middle. Shell dull white, covered with a fairly thick, gray-brown periostracum. Commonly dredged in cold waters. There are several other deep-water species on both of our coasts but they occur in very deep water. 254 American Seashells Family MARGINELLIDAE Genus Marginella Lamarck 1799 Subgenus Eratoidea Weinkauff 1879 Marginella haematita Kiener Carmine Marginella Figure 56a Southeast Florida and the West Indies. % inch in length, characterized by its glossy, bright and deep rose color, 4 strong columella teeth, pointed spire and thickened outer lip whose inner edge bears about 15 small, round teeth. Uncommon from 25 to go fathoms. M. philtata M. Smith and M. jaspidea Schwengel are probably this species. Marginella denticulata Conrad Tan Marginella Figure 56c North Carolina to both sides of Florida and the West Indies. ¥g inch in length, similar to haematita, but with a longer spire, only 7 to g teeth on the outer lip, with a shallow U-shaped notch at the top of the aperture, and the entire shell is yellow-tan to whitish. Uncommon from low tide to 600 fathoms. M. eburneola Conrad is this species. Marginella aureocincta Stearns Golden-lined Marginella Figure 56b North Carolina to both sides of Florida and the West Indies. %4¢ inch (4.0 mm.) in length; aperture half the length of the entire shell; spire pointed. Outer lip thickened, with about 4 very small teeth just inside the aperture. Columella with 4 strong folds or teeth. Color translucent- white, with two distinct, narrow spiral bands of light tan-orange on the body whorl (1 showing in the whorls of the spire). A very common species from low-water line to 90 fathoms. Genus Prunum Herrmannsen 1852 Prunum carneum Storer Orange Marginella Plate rik Southeast Florida and the West Indies. %4 inch in length, very glossy; outer lip thickened, smooth and white. Apex half covered by a callus of enamel. Lower third of columella with 4 strong, slanting teeth. Shell bright orange with a faint, narrow, whitish, spiral band on the middle of the whorl and one just below the suture. Un- common in Florida on reef flats to 6 fathoms. Prunum roosevelti Bartsch and Rehder Roosevelt’s Marginella Plate 11-0 The Bahamas. Figure 56. Marginellas. a, Marginella haematita Kiener; b, M. aureocincta Stearns; c, M. denticulta Conrad; d, Prunum bellum Conrad; e, Prunum amabile Redfield; f, P. limatulum Conrad; g, P. apicinum Menke; h, P. vir ginianum Conrad; i, Hyalina avena Val.; j, Persicula catenata Montagu; k, H. avenacea Deshayes; |, H. torticula Dall; m, Persicula minuta Pfeifer; n, Gibberulina pyriformis Cpr.; 0, G. ovuliformuis Orb. (m and o X10, the others X5). 256 American Seashells 1 inch in length, extremely close to carneum, differing only in being larger, and in having a brown spot on the apex and 2 large chocolate spots on the outer lip. There may be also 2 smaller spots at the anterior end of the shell. Apparently rare and possibly a color form of carneum. I have seen only 3 specimens, Prunum labiatum Valenciennes Royal Marginella Plate 11] Off Texas to Central America. 1 to 144 inches in length, similar to carneum, but stouter, lip orange- brown, body whorl whitish gray with 3 darker, subdued spiral bands. Outer lip with small teeth on its inner edge. Very uncommon, but has been found off Yucatan by shrimp fishermen, The Texas record is open to question, Subgenus Leptegouana Woodring 1928 Prunum guttatum Dillwyn White-spotted Marginella Plate 11m Southeast Florida and the West Indies. % to %4 inch in length; outer lip smooth, white and with 2 or 3 brown spots on the lower half. 4 columella teeth. Color of body whorl pale whitish with 3 obscure bands of light pinkish brown, and irregularly spotted with weak, opaque-white, roundish dots. Not uncommon in shallow water. Prunum bellum Conrad La Belle Marginella Figure 56d Off North Carolina to Key West. % inch in length, glossy, white, sometimes with a bluish-gray undertone. Sometimes with a rose tint on the body whorl. Spire moderately elevated. Outer lip thickened, without teeth. Lower half of columella with 4 strong, equally sized teeth. Commonly dredged from 1 to 200 fathoms. Prunum amabile Redfield Queen Marginella Figure 56e Off North Carolina to Key West. ¥s inch in length, similar to bellum, but with a shorter spire, more slant- ing columellar teeth, colored a translucent-tan with a heavy suffusion of orange on the shoulder of the whorl which becomes lighter on the lower part of the whorl. There is a fairly well-developed, white callus on the parietal wall. Uncommonly dredged from 25 to 125 fathoms. MARGINELLIDAE 254 Prunum apicinum Menke Common Atlantic Marginella Plate 11n; figure 56g North Carolina to Florida, the Gulf States and the West Indies. % inch in length, glossy, with a dark nuclear whorl. Outer lip thick- ened, smooth, white, with 2 small, red-brown dots near the middle and a smaller one at the very top and very bottom. Body whorl golden to brown- ish orange with 3 subdued, wide bands of darker color. A very common, shallow-water species. About 1 in every 5000 specimens is sinistral. Prunum limatulum Conrad Boreal Marginella Figure 56f Virginia to South Carolina. % inch in length, similar to apicinum, but with a higher spire, milky- cream color, with 3 faint, spiral bands of mauve or weak orange. Outer lip not sinuate, and is usually marked with 4 spots. Nucleus white, while in apicinum it is usually bright pink. Not uncommon from 18 to 132 fathoms. Marginella borealis Verrill is the same. Prunum virginianum Conrad Virgin Marginella Figure 56h North Carolina to west Florida and Yucatan. % inch in length, similar to apicinum, but without spots on the thick varix; the third columella tooth is the largest; color of last whorl whitish to cream, often with a faint curdling of darker orange-cream, and with a deeper, suffused band just below the suture and at the base of the shell. Mod- erately common, 14 to 56 fathoms. Genus Persicuta Schumacher 1817 Persicula catenata Montagu Princess Marginella Figure 56) Southeast Florida and the West Indies. ¥% inch in length, glossy; apex sheared off and sealed over by a weak callus. Columella teeth 7. Inside of outer lip with about 20 to 25 small teeth. Color translucent grayish with 7 spiral rows of teardrop-shaped, opaque- white spots and with 2 very subdued, wide spiral bands of light-brown. Uncommon in shallow water to 92 fathoms. Subgenus Gibberula Swainson 1840 Persicula minuta Pfeiffer . Snowflake Marginella Figure 56m South half of Florida and the West Indies. 258 American Seashells % inch in length, resembling a miniature apicinum, but pure white in color. Like Gibberulina ovuliformis, but the aperture 1s not so long and has microscopic, spiral teeth inside the thin, curled-in outer lip. Columella with 4 oblique folds. Alias M. Javalleana Orb. Common in shallow water to 4o fathoms. The subgenus Granula Jousseaume 1874 1s this subgenus. Persicula jewetti Carpenter ewett’s Marginella J p gl Monterey, California, to Lower California. % inch (5.0 mm.) in length, snow-white, glossy, rather stout. Apex smoothed over and obscured. Outer lip smooth, slightly curled inward. Col- umella with 3 or 4 rather distinct, slanting, spiral folds with several smaller ones higher on the columella. Common from low tide to several fathoms. There are 3 similar, small and white species which are very difficult to separate; and according to some workers, size and proportionate dimensions are of significance: P. regularis Cpr. (Regular Marginella), Monterey to Lower California. Length 3.3 mm., ratio of diameter to length 1 to 1.5. Low tide to 30 fathoms. Common. P. subtrigona Cpr. (Triangular Marginella), Monterey to Lower Cali- fornia. Length 3.5 mm., ratio of diameter to length 1 to 1.25. Low tide to 50 fathoms. Uncommon. P. politula Dall (Polite Marginella), Santa Barbara to Lower California. Length 3.0 mm., ratio of diameter to length 1 to 2. Low tide to 20 fathoms. Uncommon. Genus Hyalina Schumacher 1817 Subgenus Volvarina Hinds 1844 Ayalina avena Valenciennes Orange-banded Marginella Plate 11p; figure 561 North Carolina to Key West and the West Indies. 4 to % inch in length, slender; spire pointed, but short. Outer lip curled in, white and smooth. Aperture narrow above, wide below. 3 to 4 slanting, columellar teeth. Color whitish, cream or yellowish with 4 to 6 spiral bands of subdued orange-tan. A moderately common, shallow-water species. The pink variety, especially common in Yucatan has been given the name beyer- leana Bern. Hyalina veliei Pilsbry — . Velie’s Marginella West coast of Florida. MARGINELLIDAE 259 ¥ inch in length, somewhat like our figure 56e, but with a higher, more pointed spire. Shell quite thin for a Marginella; color yellowish to whitish and somewhat translucent. Outer lip thickened, pushed in at the middle and white in color. Columella with 4 very distinct folds. Common in shallow water inside dead Pinna shells on mangrove mud flats. Hyalina avenacea Deshayes Little Oat Marginella Figure 56k North Carolina to both sides of Florida and the West Indies. ¥ to % inch in length, slender, very similar to H. avena, but usually smaller, with a longer spire, more slender anterior end, and pure, opaque- white in color, except for a very faint hint of straw color below the suture, again at the middle of the body whorl and also near the base. Common from shallow water to 750 fathoms, This is avenella Dall and succinea Conrad. Hyalina torticula Dall Knave Marginella Figure 56] Off eastern Florida. ¥, inch in length, slender, fusiform, with a tall spire which is leaning to one side. Color opaque-white, glossy, and with a hint of straw-colored bands. Possibly a sport of avenacea. Uncommon in deep water. Hyalina californica Tomlin Californian Marginella Santa Monica, California, to Mexico. ¥, inch in length, slender, aperture % the length of the entire shell, with 4 whorls, and colored a grayish to bright-orange with 3 distinct or obscure, rather wide, spiral bands of white. Lower third of columella white and with 4 distinct, spiral folds. Outer lip smooth, rounded, pushed in slightly, espe- cially near the central portion. Moderately common in rocky rubble under stones at dead low tide. Genus Gibberulina Monterosato 1884 (Cypraeolina Cerulli-Irelli 1911) Gibberulina ovuliformis Orbigny Teardrop Marginella Figure 56-0 North Carolina to both sides of Florida and the West Indies. ¥% inch (2.5 mm.) in length, globular, glossy, opaque-white. Aperture as long as the shell. Apex hidden under top of outer lip. Upper part of whorl slightly shouldered. Lower third of columella with 3 or 4 small, slanting 260 American Seashells teeth. Outer lip thickened. Do not confuse with Persicula minuta Pfr. Com- mon in shallow water to several fathoms. Alias Jacrimula Gould, hadria Dall and amianta Dall. Gibberulina pyriformis Carpenter Pear-shaped Marginella Figure 56n Izhut Bay, Alaska, to Gulf of California. Ys inch (3 mm.) in length; aperture as long as the shell. Glossy, trans- lucent milk-white. Lower columella with 4 fairly strong folds with several microscopic teeth farther above. Outer lip curled in and with about 30 microscopic teeth. Animal black. Very common all along the Pacific coast from low-tide line to 40 fathoms. On mud, gravel or backs of abalones. Family CONIDAE Genus Conus Linné 1758 Conus spurius atlanticus Clench Alphabet Cone Plate 14p Florida and the Gulf of Mexico. 2 to 3 inches in length; spire slightly elevated in the center. Top of whorls smooth, except for tiny growth lines. Color white with spiral rows of orange-yellow squares. Interior of aperture white. A rather common and attractive species found in shallow water. True spurius spurius Gmelin from the Bahamas and Antilles differs only in having the spots merging into occa- sional mottlings. Another race occurs off Yucatan in which the spots are sometimes smaller and‘a rather dark bluish purple. Conus aureofasciatus Rehder and Abbott Golden-banded Cone Plate 142 Tortugas to off Yucatan, Mexico. 2 to 3 inches in length, similar in shape to spurius, although sometimes more slender. Characterized by several spiral bands of light-yellow. Dredged in several fathoms of water. Uncommon to rare. It is possible that this spe- cies may be only a freak color form of spurius. Conus daucus Hwass Carrot Cone Plate 14a Both sides of Florida and the West Indies. 1 to 2 inches in length. Spire rather low, sometimes almost worn flat. Shoulder even and sharp. Spire with small, spiral threads. Color deep, solid orange to lemon-yellow, rarely with a lighter band. Spiral rows of minute CONIDAE 261 brown dots sometimes present on sides. Interior of aperture pinkish white. Color of spire is orange with large white splotches. Uncommon below 15 feet of water. Conus juliae Clench Julia’s Cone Plate 14b Off northeast Florida to Tortugas. 1% to 2 inches in length. Spire moderately high, flat-sided and with about 10 to 12 whorls. Shoulders of whorls slightly rounded; sides nearly flat. Color a pale pinkish brown to orangish with a moderate and indistinct band of cream or white at the mid area. This is overlaid with a series of fine spiral, broken lines or dots of brown. Spire whitish with axial, zigzag, reddish brown streaks. A choice collector’s item. Named after Mrs. William J. Clench, a great contributor to the cause of malacology, Conus floridanus Gabb Florida Cone Plate 14d North Carolina to both sides of Florida. 1% to 1%4 inches in length. Spire well-elevated and slightly concave. Sides of whorls flat. The top of each whorl in the spire is concave and also has faint lines of growth. Color variable: usually white with elongate, rather wide patches of light orange-yellow to yellow. Spire with splashes of color. There is usually a white, spiral band around the middle of the whorl which may have small dots of yellowish brown. Moderately common in shallow water to 7 fathoms. Conus floridanus floridensis Sowerby (pl. 14e) is an extremely dark color form with spiral rows of reddish brown dots and heavier mottlings. C. floridanus burryae Clench is another color form from off the Lower Florida Keys in which the spiral rows of brownish dots merge into solid lines. The lower end of the shell in very dark brown to deep brownish black. Un- common. Conus sennottorum Rehder and Abbott Sennotts’ Cone Plate 14h Gulf of Mexico, from Tortugas to Yucatan. 1 inch in length, with a glossy, smooth finish. Slightly turnip-shaped. Color variable: white to bluish white with spiral rows of very small brown dots. Yellowish-brown maculations may be present. Moderately common in 18 fathoms off Yucatan. Named after John and Gladys Sennott. Conus sozoni Bartsch Sozon’s Cone Plate 14c South Carolina to Key West and the Gulf of Mexico. 262 American Seashells 2 to 4 inches in length. Spire elevated, slightly concave, with the top of each whorl also concave and with fine, arched lines of growth. There are 10 to 12 small spiral ridges at the lower end of the shell. Sides of whorls flat. Color as shown in the photograph, with the two whitish spiral bands being characteristic. Large and perfect specimens are collector’s items, although individuals less than 2 inches in length are rather commonly dredged in 50 feet of water off both sides of Florida. Beach specimens have been collected on rare occasions. Named after the sponge diver, Sozon Vatikiotis. Conus regius Gmelin Crown Cone Plate 14m Southern Florida and the West Indies. 2 to 3 inches in length. Spire low; shoulders of whorls with low, irreg- ular knobs or tubercles. Color very variable even in the same locality. A rare yellowish color form (citrinus Gmelin, not Clench 1942) occurs in the Lower Florida Keys, Cuba and the Antilles. The interior of the aperture of this species is white. Uncommon in Florida. Conus mus Hwass Mouse Cone Plate 14-0 Southeast Florida and the West Indies. 1 to 1% inches in length. Spire elevated somewhat. Shoulders of whorls with low, irregular, white knobs, between which are brown splotches. Color a dull bluish gray with olive-green or brown mottlings. Interior of aperture with 2 wide spiral bands of subdued brown. Periostracum thick, velvety and yellowish to greenish brown. The name Conus citrinus Gmelin (erroneously applied to this species in Johnsonia and other books) is actually the yellow form of regius. The Mouse Cone is very common in intertidal, reef areas. Conus stearnsi Conrad Stearns’ Cone Plate 22y North Carolina to both sides of Florida to Yucatan. % to % inch in length. A small, slender, graceful cone with a high spire. Top of whorls concave. Sides almost flat. Color usually dull grayish with rows of tiny, white squares and with dull, yellowish brown streaks or mot- tlings. Highly colored specimens may have rich reddish brown mottlings. Moderately common from shallow water to 30 feet in sand. Do not confuse with jaspideus. Conus jaspideus Gmelin Jasper Cone Plates 14n; 22x South half of Florida and the West Indies. CONIDAE 263 % to % inch in length; very similar to stearnsi, but generally more brightly hued with larger, reddish brown mottlings. The shell is fatter, with more rounded sides, and has strong, spiral lines cut into the sides, usually right up to the shoulder. A very common shallow, sand-loving species. C. peali Green is the same species. Conus verrucosus Hwass W arty Cone Plate 22z Southeast Florida and the West Indies. %4 to 1 inch in length. A heavy, small cone with a rather high spire and slightly rounded sides. It has small knobs on the shoulder of the last whorl and about 1o spiral rows of distinct warts on the sides. Color white to yel- lowish with large, brown or yellow mottlings. Uncommon just offshore along the Lower Keys. Common in the West Indies. A color form, vanhyningi Rehder, is a deep, rich peach with the interior of the aperture also pink. Conus stimpsoni Dall Stimpson’s Cone Plate 14) Southeast Florida and the Gulf of Mexico. 1% to 2 inches in length. A simple cone with a sharp, slightly concave, rather high spire, and with flat sides. It is usually smooth, but may have 15 to 20 cut spiral lines on the sides. Color is an even wash of yellowish white, but sometimes with 2 or 3 slightly darker, wide, yellowish spiral bands. Periostracum gray and rather thick. We have figured the holotype (speci- men which Dall used in describing the species). Uncommon in rather deep water down to 30 fathoms. Conus villepini Fischer and Bernardi Villepin’s Cone Plate 14f Tortugas to Yucatan. 1% inches in length. Spire rather well elevated, very slightly concave. Each whorl in the spire is concave, with 3 to 4 spiral threads, and with fine, arched growth lines. Sides of shell smooth and slightly convex. There are about 9 indistinct spiral threads at the bottom end of the shell. Color of the thin periostracum is light yellowish brown. Shell light grayish white with a faint pinkish undertone. There are 3 or 4 long, irregular, axial streaks of dark reddish brown on the sides of the last whorl. Interior of aperture blushed with rosy-white. We have illustrated the holotype of amphiurgus Dall in color which is a synonym. Rare in deep water. 264 American Seashells Conus mazei Deshayes Maze’s Cone Plate 14k Southeast Florida and the West Indies. 17 to 2 inches in length. A long, narrow, and very handsome species which has rows of delicate beads on the very high spire. This is probably the most valuable cone in Florida waters. A few fortunate collectors in Florida have dredged this unusual cone. Conus granulatus Linneé Glory-of-the-Atlantic Cone Plate 14] Southeast Florida and the West Indies. 1 to 1% inches in length. A fairly slender cone with rounded whorls in the spire which have spiral threads. Colored a brilliant orange-red to bright- red with flecks of brown and gold. Coarse spiral threads are usually present on the sides. Interior of aperture with a rosy-pink blush. A perfect specimen of this species is, indeed, a collector’s item. It is very rare in Florida and not at all common in the West Indies. It lives in reefs just offshore. « Conus austini Rehder and Abbott Austin’s Cone Tortugas to Yucatan and West Indies. 2 to 2% inches in length, pure white in color, although some may have a yellow-brown apex. Characterized by numerous odd-sized spiral threads on the sides. Sides of whorls flat to slightly rounded. Shoulders sharp to slightly rounded. Top of whorls slightly concave, with one smooth spiral carina and several much smaller threads. Shell sometimes with axial puckerings or rib- like wrinkles. Periostracum velvety and grayish brown. Rare off Florida but common in 20 fathoms off Yucatan. Conus clarki Rehder and Abbott Clark’?s Cone Plate 141 Off Louisiana. 1 to 1% inches in length, whitish in color and with small weak spots, rather turnip-shaped, similar to austini, but with 27 to 30 very strong, squar- ish spiral cords on the sides. The cords, and especially the one at the shoulder, are strongly beaded. Between the cords there are microscopic, axial threads. Periostracum gray. Apparently rare offshore in 29 fathoms. This and the preceding species were named after Austin H. Clark, scientist, author and gentleman. C. frisbeyae Clench and Pulley 1952 is unquestionably this spe- ies; TEREBRIDAE 265 Conus californicus Hinds Californian Cone Farallon Islands, California, to Lower California. %4 to 1 inch in length. Spire moderately elevated and slightly concave. The shoulders of the shell are rounded, the sides very slightly rounded. The chestnut to pale-brown, velvety periostracum is rather thick. Shell grayish white in color. Interior whitish with a light-brown tint. Rather common in shallow water along certain parts of southern California. Family TEREBRIDAE Genus Terebra Bruguiere 1789 Terebra dislocata Say Common Atlantic Auger Plate 261 Virginia to Florida, Texas and the West Indies. 1% to 2 inches in length, slender. Whorls with about 25 axial ribs per whorl which are divided 1% to % their length by a deep, impressed, spiral line. Many specimens show prominent, squarish, raised spiral cords between the ribs. Columella with 2 fused spiral folds near the base. Color a dirty, pinkish gray, but sometimes orangish. A common shallow-water species. Terebra taurina Solander Flame Auger Plate 13h Southeast Florida, the Gulf of Mexico and the West Indies. 4 to 6 inches in length, heavy, rather slender. Characterized by a cream color with 2 spiral rows of axial, red-brown bars, the upper series being twice as long as the lower one. Upper whorls faintly and axially ribbed. Upper half of each whorl swollen and with a single incised line. T. flammea La- marck and T. feldmanni Roding are this species. Formerly considered quite rare, but now not infrequently dredged in the Gulf of Mexico. Terebra floridana Dall Florida Auger Off South Carolina to south Florida. 2 to 3 inches in length, very long and slender. Color light-yellow to yellowish white. Each whorl has just below the suture a row of about 20 oblong, slightly slanting, smooth axial ribs. Below this, and separated from it by an impressed line, is a similar row of much shorter, axial ribs. The lower third of the whorl is marked by 3 or 4 raised, spiral threads only. Columella with a single, strong fold near the bottom, A fairly rare species, 266 American Seashells Terebra concava Say Concave Auger Plate 26) North Carolina to both sides of Florida. *% inch in length, slender, about 12 whorls, semi-glossy, and with slightly concave whorls. Whorls in spire with a large, heavily nodulated or beaded, swollen spiral cord just below the suture. Above the suture there is a spiral series of 20 very small beads per whorl. The concave middle of the whorl bears about 5 microscopic, incised spiral lines. Color yellowish gray. Com- mon in shallow water. Do not confuse with the larger yellow T. floridana which has 2 spiral rows of elongate beads just below the suture. Terebra protexta Conrad Fine-ribbed Auger Plate 26k North Carolina to Florida and Texas. %4 to 1 inch in length, about 13 whorls, dull-white in color and with a well-indented suture. Whorls in spire slightly concave with about 22 fine axial ribs running from suture to suture, but which are broken weakly by 7 to g incised spiral lines. The upper line is about %4 the way down the whorl. Several forms exist which have been given names: form Jutescens Smith has about 30 to 32 finer axial riblets per whorl which are made slightly beaded by the spiral lines; in the form Jimatula Dall, the ribs and the spiral threads are about equal in size and give a reticulated pattern. All occur together in fairly deep water and are common. Terebra hastata Gmelin Shiny Atlantic Auger Plate 26h Southeast Florida and the West Indies. 1/4 to 1% inches in length. Characterized by its smooth, highly glossy finish, its numerous axial ribs which extend from suture to suture, and by its bright yellowish color and white band below the suture. Columella smooth- ish and white. This is the “fattest” species in the western Atlantic, and is fairly common in the West Indies. Terebra cinerea Born Gray Atlantic Auger Plate 26g Southeast Florida and the West Indies. 1 to 2 inches in length, slender, with flat-sided whorls and a sharp apex. Numerous small riblets extend halfway down the whorls (about 45 to 50 per whorl). Color all cream or bluish brown; sometimes with darker spots below the suture. Surface with exceedingly fine, numerous rows of pin- pricks which give the shell a silky appearance under the lens. Moderately common in shallow water. Compare with salleana Deshayes. RORRIDAE 267 Terebra salleana Deshayes Salle’s Auger North Florida to Texas and Colombia. 1 to 1¥% inches in length, similar to cimerea, but always a dark bluish gray or brownish, with fewer, larger punctations, with about 30 ribs per whorl, and with a purple, not white, nucleus. Common in shallow water. Terebra pedroana Dall San Pedro Auger Redondo Beach, California, to Lower California. 1 to 1% inches in length, strong, slender, with about 12 whorls and colored grayish to whitish yellow or brownish. Sculpture between sutures of first a fairly broad row of well to poorly developed nodules (about 15 to 18 per whorl), followed below by a flat area which is weakly and axially wrinkled or ribbed and with numerous, fine, spiral, incised lines. Siphonal canal bounded by a sharp spiral line on the outer shell. Fairly common in shallow water. Family TURRIDAE The family Turridae is a very large and diverse group of toxoglossate gastropods which are very difficult to classify. A book of this size cannot do justice to the many interesting species found in our waters. The family prob- ably contains no less than 500 genera and subgenera and several thousand species. An interesting and valuable review of the family is given by A. W. Powell in the Bulletin of the Auckland Institute and Museum, no. 2, pp. 1 to 188, 1942. Those interested should consult the works of Grant and Gale, Bartsch, Dall, Rehder, and Woodring. We have included here only a very sketchy representation of our American Turrid fauna. Subfamily TURRINAE Shells rather large, usually with a long, slender canal. Sinus on or adja- cent to peripheral keel; deep and V-shaped. Operculum leaf-shaped with an apical nucleus. Radula with only 2 marginals which are wish-bone in shape. Genus Gemmula Weinkauff 1875 Gemmula periscelida Dall Atlantic Gem Turret Figure 57¢ North Carolina to Yortugas, Florida. 1% to 2 inches in length, heavy and with the sinus or anal notch well below the suture. Color ash-gray. See illustration. Rare in 100 fathoms. 268 American Seashells Genus Polystira Woodring 1928 Polystira albida Perry White Giant Turret Plate 13] South Florida, the Gulf of Mexico and the West Indies. 3 to 4 inches in length, pure-white in color. P. virgo Lamarck, and “Wood” are this species. Not uncommonly dredged in the Gulf of Mexico. Polystira tellea Dall Delicate Giant Turret Plate 13m Off southeast Florida. 3 to 3% inches in length. Grayish white. Sculpture not so distinct nor so smooth as in albida. Not uncommonly dredged off Key West. Do not confuse this and the preceding species with Fusinus couei (pl. 13d). Subfamily COCHLESPIRINAE Shell with a long canal. Sinus on the shoulder, rounded, broad and shal- low to rather deep. Operculum variable. Radula with 2 strong marginals and a very large central. Shell thin with a sharply angled periphery. Genus Ancistrosyrinx Dall 1881 Ancistrosyrinx radiata Dall Common Star Turret Figure 57e South Florida, the Gulf of Mexico and the West Indies. ¥ inch in length. A delicate, glossy, translucent and highly ornamented species. Anterior canal very long. Shoulders keeled, with numerous, small, sharp, triangular spines. Commonly dredged from 30 to 170 fathoms. A. elegans Dall (Elegant Star Turret) from about 200 fathoms off Key West is 2 inches in length, more elongate, with more numerous and duller spines on the sharp shoulder. Very rare. Subfamily CLAVINAE Shell between 4 and /% inch in length, spire tall and the anterior canal short. Sinus on the shoulder, moderately to deeply U-shaped, often rendered subtubular by a parietal tubercle. Operculum with an apical nucleus. Radula variable. Genus Crassispira Swainson 1840 Crassispira ebenina Dall Dall’s Black Turret Figure 57} Southeast Florida and the West Indies. *4 inch in length; a solid brown-black in color and with a slight sheen. Figure 57. American Turret and Mangelia Shells. ATLANTIC: a, Kurtziella limonitella Dall, % inch; b, Inodrillia aepynota Dall, % inch; ce, Gemmmula perisce- lida Dall, 2 inches; d, Monilispira leucocyma Dall, % inch; e, Ancistrosyrinx radiata Dall, % inch; f, Cerodrillia thea Dall, % inch; g, Genota viabrunnea Dall, 2 inches; h, Gymnobela blakeana Dall, 4 inch; i, Mangelia morra Dall, %4 inch; j, Crassispira ebenina Dall, 34 inch; k, Mangelia corbicula Dall, 1% inch. PACIFIC: 1, Mitromorpha filosa Cpr., ¥ inch; m, Mitromorpha aspera Cpr., % inch. 270 American Seashells 15 short axial ribs per whorl. Spiral threads numerous and fine. Sinus small, its posterior end round, its opening narrow. Not uncommon below low water under rocks. C. sanibelensis Bartsch and Rehder is similar, but 1 inch in length, with g longer and wider axial ribs, with a large slit, and colored orange-chestnut with white between the ribs. Uncommon around Sanibel Island. Subgenus Crassispirella Bartsch and Rehder 1939 Crassispira ostrearum Stearns Oyster Turret Plate 26n North Carolina to south half of Florida. Cuba. ¥s to % inch in length; light yellow-brown to chestnut. Sinus U-shaped. About 20 weakly beaded axial ribs per whorl. Just below the suture there is a single, smooth, strong spiral cord. Spiral threads moderately strong to weak (16 to 20 on the last whorl, 4 between sutures). Lower part of outer lip thin and strongly crenulate or wavy. Common from low water to 90 fathoms. C. tamzpaensis Bartsch and Rehder is very similar, and may be this species. Genus Cerodrillia Bartsch and Rehder 1939 Cerodrillia perryae Bartsch and Rehder Perry’s Drillia West coast of Florida. % inch in length, flesh-colored, with a broad, golden-brown band around the periphery. 8 to 9 axial ribs per whorl. Faint spiral lines present. Not uncommon. C. thea has shorter axial ribs and is uniform chocolate- brown. Cerodrillia thea Dall Thea Drillia Figure 57f West coast of Florida. % inch in length, thick-shelled, with a glossy-brown finish, and with the short, slanting ribs cream in color. Outer lip prominent. Sinus deep and U-shaped. Uncommon in shallow water. Genus Monilispira Bartsch and Rehder 1939 Monilispira albinodata Reeve White-banded Drillia Southeast Florida and the West Indies. % inch in length, resembling a Cerithium in shape; color dark blackish TURRIDAE 271 brown with a white band bearing about 13 knobs per whorl. Last whorl with 2 or 3 spiral white bands. Fairly common in shallow water under rocks. M. albomaculata C. B. Adams is a similar species from the West Indies and is figured on plate 26f. Monilispira leucocyma Dall White-knobbed Drillia Figure 57d South half of Florida and the West Indies. ¥% inch in length. One nuclear whorl smooth. Shell dark to light grayish brown with the nodules white. Aperture dark-brown. A common shallow-water species. Genus Inodrillia Bartsch 1943 Subgenus /nodrillara Bartsch 1943 Inodrillia aepynota Dall Tall-spired Turret Figure 57b North Carolina to northeast Florida. % inch in length; chalk-white to pinkish white. Moderately common from 63 to 120 fathoms. Subfamily CONORBIINAE Shell conoidal; sinus broad and shallow, occupying the width of the shoulder. Operculum absent in Genota. Radula with 2 slender marginals only. Genus Genota H. and.A. Adams 1853 Genota viabrunnea Dall Brown-banded Genota Figure 57g Southeast Florida and the West Indies. 1% to 2 inches in length, heavy and thick-shelled. Sculpture of nu- merous spiral rows of very fine, glossy beads. Color yellowish to orangish white with a spiral, suffused band of light-brown well below the suture. Nucleus dark-brown and with tiny arched, smooth ribs. Anal sinus very wide. Rare from 100 to 350 fathoms. Subfamily MANGELINAE Shell small, ovate or fusiform, with a short canal and without an oper- culum. Sinus on shoulder usually very shallow. Radula with 2 slender marginals. 2 F/ 5) American Seashells Genus Mangelia Risso 1826 Mangelia morra Dall Morro Mangelia Figure 571 Off north Carolina to Tortugas. % inch in length, yellowish tan. Anal notch deep. 16 to 450 fathoms. Common. Provisionally placed in this genus. Mangilia is a misspelling. Genus Glyphostoma Gabb 1872 Gly phostoma gabbi Dall Gabb’s Mangelia Florida, the Gulf of Mexico and the West Indies. % inch in length. The 3 nuclear whorls are smooth and with a single, strong carina at the periphery. Shell white with 2 wide spiral bands of rose- brown on the whorl. The upper one is interrupted by about 15 short white ribs per whorl. Fine spiral threads numerous. Notch deep, with thickened, rounded sides, Varix strong. Moderately common from 30 to 150 fathoms. Genus Rubellatoma Bartsch and Rehder 1939 Rubellatoma rubella Kurtz and Stimpson Reddish Mangelia North Carolina to southeast Florida. % inch in length. Sinus shallow and U-shaped. Axial ribs long and rounded (about 9 per whorl). Spiral sculpture of numerous incised lines. Color grayish cream with light reddish between the ribs. Commonly dredged from 9 to 80 fathoms. R. diomedea Bartsch and Rehder from Sanibel Island is extremely similar, but is more brightly colored with a wide spiral band of reddish brown. Uncommon to rare. Genus Kurtziella Dall 1918 Kurtziella limonitella Dall Punctate Mangelia Figure 57a North Carolina to both sides of Florida. ¥e inch in length, semi-translucent and yellowish white. Sinus widely V-shaped. Between the strong, rounded, axial ribs there are numerous rows of microscopic opaque-white punctations. Uncommon from a few to 48 fathoms. TURRIDAE 273 Subfamily BORSONIINAE Shell biconic or fusiform in shape; sinus on the shoulder, poorly devel- oped. Operculum present or absent. Radula with 2 slender marginals. Shell usually with columella plications. Genus Gymmnobela Verrill 1884 Gymnobela blakeana Dall Blake’s Turret Figure 57h North Carolina to the Lower Florida Keys. ¥% inch in length. Sinus barely discernible. Shell thin but strong. Color translucent-white or chalky-white. Nuclear whorls distinct, without strong sculpturing and light-brown in color. Uncommon from 70 to 140 fathoms. Genus Mitromorpha P. P. Carpenter 1865 Mitromorpha filosa Carpenter Filose Turret Figure 571 Monterey, California, to the Gulf of California. 6 inch in length, solid, light orange-brown in color. Spiral cords may be slightly beaded in some specimens. Uncommon offshore. Mitromorpha aspera Carpenter Beaded Turret Figure 57m Monterey, California, to the Gulf of California. %6 inch in length, strongly beaded and somewhat cancellate, with a glossy finish and light orange-brown in color. Moderately common off- shore. Subfamily DAPHNELLINAE Shell fusiform or ovate, canal short. Operculum absent. Sinus adjoin- ing the suture. The protoconch has diagonally cancellate sculpturing. Radula with 2 slender, curved marginals only. Genus Daphnella Hinds 1844 Dapbnella lymneiformis Kiener Volute Turret Southeast Florida and the West Indies. % to ¥% inch in length; resembles a miniature, elongate Scaphella volute- shell. With about 8 whorls, the nuclear ones smoothish, the next 4 with 274 American Seashells strong, axial ribs, but the last 2 whorls with only numerous fine spiral threads crossed by exceedingly fine growth lines. Aperture elongate, rather ex- panded and a little flaring below. Sinus moderately large and simple. Color cream with yellowish brown maculations. Uncommon from shallow water to 25 fathoms. Subclass OPISTHOBRANCHIA (Bubble-shells, Pteropods, Sea Slugs) Order ONCHIDIATA Family ONCHIDIIDAE Genus Onchidella Gray 1850 Without a shell, animal slug-like, low, oval, with two short tentacles or eyestalks at the end of which are the eyes. Mantle entirely covering the back; respiratory, anal and female genital pores at the posterior underside; male pore below the right tentacle and above the sensory lobe. Shallow water to intertidal. Formerly placed in the pulmonates, but now believed to be an early offshoot of the opisthobranchs. See Freter, 1943. MANTLE SENSORY Loge CAVITY OPENING PNEUMOSTOomeE FEMALE MALE OPENING OPENING BEHIND LOBE MANTLE CILINRY GROOVE Figure 58. Underside of the marine slug, Onchidella, ¥ inch. Onchidella floridana Dall Florida Onchidella West coast of Florida, the Lower Keys and Bermuda. % inch in length, uniform slaty-blue to dark-gray; underside bluish white, with a greenish tinge to the veil. Dorsal surface velvety. Mantle margin with about 100 whitish, elongate tubercles. Common along the shore at low tide. Lives in rock crevices in nests, returning home after browsing at low tide. Onchidella carpenteri Binney Carpenter’s Onchidella Puget Sound to Lower California. ACTEONIDAE ps I/e) 5 mm. in length; body oblong, with its ends circularly rounded; upper surface regularly arched; uniform smoke-gray in color. Fresh specimens are needed to make a better description. Littoral to shallow water. Habits not known. Onchidella borealis Dall Northwest Onchidella Alaska to Coos Bay, Oregon. 8 to 12 mm. (% inch) in length; back regularly arched but a little pointed in the middle, smooth or very finely granulose, tough and coriaceous. Color black or gray, with dots and streaks of yellowish white; foot light- colored, also the head and tentacles. On rocks near high-tide mark. Gre- garious. Common. Order TECTIBRANCHIA (Bubble-shells, Sea-hares) Family ACTEONIDAE Genus Acteon Montfort 1810 External shell with a prominent spire; cephalic disk divided; operculum thin, corneous. Erroneously spelled Actaeon. Acteon punctostriatus C. B. Adams Adams’ Baby-bubble Plate 26t Cape Cod to the Gulf of Mexico and the West Indies. 3 to 6 mm. in length, solid, moderately globose, with a rather high spire. Columella with a single, twisted fold. Lower half of body whorl with nu- merous spiral rows of fine, punctate dots. Color white. Commonly found from low tide to 60 fathoms. Acteon punctocaelatus Carpenter Carpenter’s Baby-bubble British Columbia to Lower California. 10 to 20 mm. (%4 inch) in length, solid, oblong, 4 to 5 whorls, with two broad, ashy or brown spiral zones and about 26 spiral grooves on the body whorl. Columella obliquely truncated at base, and with one spiral fold. Base stained orange. Commonly found in shallow water in sand. A. vancouverensis Oldroyd is the same species. Acteon candens Rehder Rehder’s Baby-bubble North Carolina to southeast Florida and Cuba. 276 American Seashells 7 to 10 mm. in length, very similar to punctostriatus, but larger, very much thicker-shelled, glossy, opaque milk-white with light orange-brown suffusions on the body whorl. Commonly dredged in a few fathoms of water. Family RINGICULIDAE Genus Ringicula Deshayes 1838 Ringicula semistriata Orbigny Orbigny’s Helmet-bubble Plate 26v North Carolina to southeast Florida and the West Indies. 2 to 3 mm. in length, thick-shelled, resembling a miniature Phalium or Scotch Bonnet. 4 globose whorls, spire elevated. Aperture oblong; columella thickened by 3 folds, 1 above, 2 below. Outer lip very thick, swollen in the middle by a large tooth. Whorls, white, smooth, except for fine striations on the base. Not uncommonly dredged from 34 to 107 fathoms. R. nitida Verrill (Verrill’s Helmet-bubble from Maine to the Gulf of Mexico. 100 to 500 fathoms) is exteriorly smooth, with a simple, thickened outer lip, and with 2 smaller, spiral ridges on the columella. Family HY DATINIDAE Genus Micromelo Pilsbry 1894 Micromelo undata Bruguicre Miniature Melo Plate 26u Lower Florida Keys and the West Indies. ¥% inch in length, oval, rather thin and moderately fragile. Characterized by its whitish to cream color overlaid by 3 widely spaced, fine spiral lines of red and by many or few axial, wavy, lighter red flammules or lines. Un- common. Found at low tide. Genus Hydatina Schumacher 1817 Hydatina vesicaria Solander Brown-lined Paper-bubble Plate 13q South half of Florida and the West Indies. 1 to 1% inches in length, very thin, fragile, globose. Periostracum thin, buff to greenish. Shell characterized by many close, wavy, brown spiral lines. Animal large and colorful. Foot very broad. Moderately common in certain shallow, warm-water areas where they burrow in silty sand. For- merly called H. physis Linné which, however, is believed to be limited to the Indo-Pacific. a BULLIDAE Neil Family DIAPHANIDAE Genus Diaphana Brown 1827 Diaphana minuta Brown Arctic Paper-bubble Figure s59b Arctic Seas to Connecticut. Europe. 3 to 5 mm. in length, globose, thin, fragile, and transparent-tan in color. Last whorl globose below, constricted somewhat above. Apex large, globose, obliquely and mammillarly projecting. Suture deep. Columella long, straight, not thickened, the edge partly closing the narrow umbilicus. Moderately common from 6 to 16 fathoms. Diaphana debilis Gould, D. hiemalis Cou- thouy and D. globosa Loven are considered synonyms of this species by Lemche (1948) and other modern workers. Family BULLIDAE Genus Bulla Linneé 1758 The names Vesica Swainson 1840 and Bullaria Rafinesque 1815 have been ill-advisably used for this genus. Fortunately, the name Bulla has been conserved for this group of bubble-shells by the International Commission for Zoological Nomenclature. Bulla striata Bruguiere Striate Bubble Plate 13p West coast of Florida to Texas and the West Indies. 4 to 1 inch in length, similar to occidentalis, but larger, heavier, and with the spiral grooves well-marked toward the base of the shell and within the apical perforation. The whorls are compressed at the apical end. Colu- mella usually with a brown-stained callus. Locally common. B. amygdala Brug. is probably a smooth form of this species. Bulla occidentalis A. Adams Common West Indian Bubble Plate 26p North Carolina to southeast Florida and the West Indies. % to 1 inch in length, smooth, varying from fragile to quite strong, and from cylindrical (young) to fairly swollen. Apex deeply and narrowly perforate. Color very variable, but usually whitish with mottlings, zebra stripes and obscure bands of brown. Surface with numerous, microscopic striations. This is a very common bubble-shell which 1s found most easily at night and at low tide on grassy, mud flats. The author is often misnamed as “C. B. Adams.” 278 American Seashells Bulla gouldiana Pilsbry California Bubble Santa Barbara to the Gulf of California. 1% to 2 inches in length, rotund, fragile. Grayish brown with darker, streaked mottlings which are bordered posteriorly with cream. Periostracum dark-brown and microscopically crinkled. Collected abundantly at night. Bulla punctulata A. Adams from Lower California south is much heavier and constricted or narrowed at the top third of the shell. Family ATYIDAE Genus Atys Montfort 1810 Caribbean Paper-bubble Atys caribaea Orbigny Figure 59c Southeast Florida and the West Indies. % to % inch in length, fragile, translucent milk-white, oval-oblong, smooth except for a dozen or so very fine, incised spiral lines at both ends. Figure 59. Paper-bubbles of the Atlantic Coast. a, Retusa obtusa Montagu; b, Diaphana minuta Brown, c, Atys caribaea Orbigny; d, Atys sandersoni Dall, e, Philine quadrata S. Wood; f, Philine lima Brown. All Xs. Spire concealed, marked by a twisted, spiral, funnel-like umbilicus. Colu- mella acute, a little separated by a deep, narrow umbilicus. Common from shallow water to 90 fathoms. Sanderson’s Paper-bubble Atys sandersoni Dall Figure 59d North Carolina to southeast Florida and the West Indies. % to % inch in length, similar to caribaea, but thicker-shelled, with § ) flatter sides, deeper and wider umbilicus, and with more numerous and finer spiral lines at each end. Fairly common from shallow water to over 100 fathoms. ALY DAE 279 Genus Haminoea Turton and Kingston 1830 Key to the Atlantic Species (To determine on which side of the apical perforation the lip arises, hold the shell with the apex toward you and the apertural lip facing to the right. ) a. Apertural lip arising on the left side of the perforation, and angled near its insertion: b. Shell with numerous fine spiral grooves; % inch; yellowish to whitish; southeast Florida and the West Indies . . elegans Gray bb. Shell smooth; 34 inch; West Indies . . . . glabra A. Adams aa. Apertural lip arising on right side; not angled: c. Well-grooved spirally: d. Sides of whorls globose; % inch; amber to whitish; Cape Cod to North Carolina, common... __ solitaria Say (pl. 26s) dd. Sides of whorls flattish; 4% to % inch, translucent-white; west Floridato Texas;common . . . ....___.. succinea Conrad cc. Spiral striae absent or excessively fine; % inch, translucent greenish yellow; globose; Gulf to West Indies © |. antillarum Orbigny Pacific Coast Species Haminoea virescens Sowerby Sowerby’s Paper-bubble Puget Sound to Mexico. ¥% inch in length, very fragile, a translucent greenish yellow in color. Aperture very large and open. Upper part of outer lip high and narrowly winged. No apical hole. A common, littoral species on the open coast. H. cymbiformis Cpr. and H. olgae Dall are the same. Haminoea vesicula Gould Gould’s Paper-bubble Alaska to the Gulf of California. *4 inch in length, very fragile, similar to virescens, but with a barrel- shaped whorl (from an apertural view), proportionately smaller aperture, with a tiny apical perforation, and with a lower, more rounded wing on the upper part of the outer lip. Shell color much the same, but the thin peri- ostracum is often rusty-brown or yellowish orange. A common, littoral bay species. 280 American Seashells Family RETUSIDAE Genus Retusa Brown 1827 Retusa obtusa Montagu Arctic Barrel-bubble Figure 59a Arctic Seas to off North Carolina. 3 mm. in length, fairly fragile, smooth, stubby and with the spire com- monly slightly sunk or only a little elevated. Columella smooth. A chink- like umbilicus is present. Color translucent-white with yellowish brown stain- ing. Common from shore to 90 fathoms. R. pertenuis Mighels and R. turrita Moller are this species. Retusa sulcata Orbigny Sulcate Barrel-bubble North Carolina to southeast Florida and the West Indies. 2 mm. in length. Characterized by its small size, fine axial threads, white color, oblong shape, flat sides and deeply sunken spire. Moderately common from 3 to 95 fathoms. Retusa canaliculata Say Channeled Barrel-bubble Plate 26x Nova Scotia to Florida, Texas and the West Indies. 4 to 6 mm. in length, solid, oblong with its spire moderately elevated, but almost invariably eroded. Glossy smooth, except for microscopic growth lines. Outer lip thin, advanced above. Columella of a single, raised, strong spiral ridge. Suture slightly channeled. Nucleus (when present) very small and pimple-like. Color white to cream, commonly with dark, rust-brown staining. Acteocina candei Orbigny is probably only a southern representa- tive of this species. A common shallow-water species which was formerly placed in the genus Acteocina. Genus Pyrunculus Pilsbry 1894 Pyrunculus caelatus Bush Bush’s Barrel-bubble Plate 26w North Carolina to southeast Florida. 3 mm. in length, pyriform in shape, rather thick and opaque-white. Spire concealed within a very deep pit. Rather rare from 15 to 43 fathoms. Genus Rhizorus Montfort 1810 (Volvula A. Adams, not Gistel) Rhizorus oxytatus Bush Southern Spindle-bubble North Carolina to southeast Florida and Cuba. ACTEOCINIDAE 281 3 to 4 mm. in length, fragile, translucent-white, spindle-shaped, with a sharp, long, spike-like apex. Glossy and with 4 or 5 very fine, indistinct, punctate, spiral lines at each end. Outer lip thin, following the curvature of the body whorl to just below the middle where it continues in a straight line. Umbilicus chink-like. Periostracum thin and pale-straw. Common from 5 to 100 fathoms. R. bushi Dall comes from deep water off North Carolina. It is larger, with a long apical process and with a long, chink-like umbilicus. The genus Volvulella Newton 1891 is Rhizorus. Rhizorus acutus Orbien Spined Spindle-bubble gny P P s 4 ates?) North Carolina to southeast Florida and the West Indies. 2 to 3 mm. in length, spindle-shaped, rather oblong, fragile, except for minute spiral lines at each end. Upper end of aperture ends in a very sharp, rather prolonged spike. Umbilicus rarely, if ever, present. Commonly dredged down to 150 fathoms. R. minutus Bush is probably the young. R. aspinosus Dall from the same region has the process poorly developed, and may be a form of this species. Family SCAPHANDRIDAE Genus Scaphander Montfort 1810 Scaphander punctostriatus Mighels Giant Canoe-bubble Plate 26-0 Arctic Seas to Florida and the West Indies. 1 to 1% inches in length, very lightweight, but moderately strong. Ovate-oblong. Apex with a slightly sunken area. Aperture constricted above, roundly open below. Columella simple, rounded. Shell smoothish, except for numerous, spiral rows of microscopic, elongate punctations. Color chalk-white, with a straw periostracum. Fairly common from 20 to 1000 fathoms. Scaphander nobilis Verrill (Noble Canoe-bubble) from off New Eng- land is the same size or smaller, has a proportionately much larger aperture, its outer lip is wing-like above, and the microscopic punctations are round. It is uncommon. A figure of S. watsoni Dall is on plate 26m. Family ACTEOCINIDAE Genus Acteocina Gray 1847 Acteocina culitella Gould Western Barrel-bubble Kodiak Island, Alaska, to Lower California. 282 American Seashells 72 to % inch in length, moderately solid, oblong but more constricted at the upper portions. Spire of 5 whorls, elevated, pointed and with a tiny, pimple-like nucleus (usually eroded in northern specimens). Suture narrowly and deeply channeled. Body whorl swollen at the lower half. With numer- ous microscopic, wavy, incised spiral lines. Color yellowish, sometimes with numerous golden-yellow, fine spiral lines. Columella is a single, raised spiral cord. Common in shallow water. A. cerealis Gould is probaby the same species. Genus Cylichna Loven 1846 Cylichna gouldi Couthouy Gould’s Barrel-bubble Plate 26r Massachusetts Bay to off Cape Cod. Arctic Seas. %s inch (9 mm.) in length, fragile, chubby, with the spire usually sunk in and consisting of 4 or 5 whorls. Color dirty-white with a yellowish periostracum. The whorls are much more globose and the anterior end more constricted than in the much smaller species, Retusa obtusa. Formerly placed in the genus Retusa. Uncommon from 26 to 34 fathoms. Cylichna alba Brown Brown’s Barrel-bubble Arctic Seas to North Carolina. Bering Sea to San Diego, California. % inch (5 mm.) in length, fragile, narrowly oblong with flat sides. Apex with a dished, shallow depression. Upper %3 of aperture narrow; below it is wide. Columella short, rounded, slightly raised. Shell white, smoothish, except for microscopic, spiral scratches. Periostracum thin, shiny, yellowish, but often darkly stained with brown. Commonly dredged from 1 to 1000 fathoms in cold water. Subgenus Cylichnella Gabb 1872 Cylichna bidentata Orbigny Orbigny’s Barrel-bubble Plate 26q North Carolina, Florida to Texas and West Indies. 3 mm. in length, somewhat resembling alba, but its columella has a spiral, callous fold and an indistinct nodule below. The shell is more oval. Glossy- white. Commonly found from shallow water to 200 fathoms. This is C. biplicata of authors, not A. Adams. Family PHILINIDAE Related to the Scaphander Canoe-shells, but different in having the oo = - aainenasnenieenemmed tt ~ a - GASTROPTERIDAE 283 mantle reflexed and closed over the shell, in lacking central teeth in the radula, and in having a much more degenerate shell. Genus Philine Ascanius 1772 Philine quadrata S. Wood Quadrate Paper-bubble Figure 59e Arctic Seas to North Carolina. ¥ inch in length, moderately fragile, semi-transparent, white, squarish- oval and more constricted toward the top. Aperture large, flaring, and rounded below. Early whorls very small. Sculpture of numerous spiral rows of microscopic oval punctations. Suture deep. The narrow top of the aperture is slightly higher than the apex. Commonly dredged off the New England states from 20 to 4oo fathoms. Philine lima Brown File Paper-bubble Figure sof Arctic Seas to Cape Cod, Massachusetts. ¥% inch in length, much more oblong than quadrata, with the top of the aperture well below the apex, and sinuate from a top view. Columella fairly strong. Sculpture of spiral rows of scalloped lines forming chains, between which are a single scalloped line. Moderately common in fairly shallow but cold water. Alias P. lineolata Couthouy. Philine sagra Orbigny Crenulated Paper-bubble North Carolina to southeast Florida and the West Indies. 4 to % inch in length, oblong, fragile, white, with a large aperture, with numerous spiral lines of small oblong rings placed end to end, and char- acterized by the finely crenulated lip. Top of the aperture the same height as the apex. Not uncommon from 15 fathoms down. Family GASTROPTERIDAE Genus Gastropteron Kosse 1813 Shell entirely internal and consisting of a minute, nautiloid, calcareous spire. Body sack-shaped, with two large, wing-like, fleshy flaps, one on each side of the body. These peculiar, small sea-slugs swim through the water in a bat-like manner. Gastropteron rubrum Rafinesque Bat-wing Sea-slug Figure 6o0e West coast of Florida to the West Indies. Mediterranean. 284 American Seashells ¥% to 1 inch in length. General color varying from red-purple to pale- rose, sometimes with bluish-white spots. There is a vivid, iridescent blue border on the head disk and the “wings.” Found for the first time in the western Atlantic by Harold J. Humm in 1950 at Alligator Harbor, Florida. Rare? This is probably G. meckeli “Dall.” Figure 60. Animals of some Tectibranchs. a, Haminoea (side view, X3); b, Philine (X3); e, Scaphander (X2); d, Acteocina (X3); e, Gastropteron (Xeys f, Bulla (X3); g, Aplysia (X%); h, Bursatella (X%). (After Guiart 1901.) APLYSIDAE 285 G. pacificum Bergh from the Aleutians is similar, but yellowish with red flecks. There are 16 to 20 gill leaflets. Margin of mantle without a flagel- lum, as in rubrum. Uncommon from 9g to 15 fathoms. G. cinereum Dall (British Columbia) is 11 mm. in length, and a uniform dusky-slate color. It also lacks a posterior flagellum on the mantle. Superfamily APLYSIACEA Family APLYSIDAE Genus Aplysia Linné 1767 Dorsal lobes free, well-separated and used for swimming. Shell internal, thin, flat, horny, with little or no lime, and colored amber. Skin smoothish. They give off a harmless purple ink. Tethys is a name which was for a long time applied to this group, but it is now restricted to a nudibranch genus. Aplysia is a conserved name (see fig. 60g). Aplysia willcoxi Heilprin Willcox’s Sea-hare Cape Cod to both sides of Florida. 5 to 9 inches in length. Mantle under the lobes with a minute perfora- tion or fleshy tube above the area of the shell. Color dark-brown with slight maculations on the swimming lobes, head and neck. There are large, rounded, fairly regular, yellowish scallopings along the inner border of the lobes. Mantle and gills light-purple and yellow. Common. The form perviridis Pilsbry is clear green on the head and tentacles, the lobes olive-green with a coarse-meshed reticulation of black, subdivided by fine veins; irregularly maculated all over with light-green, with an occasional clumping of white dots. Aplysia dactylomela Rang Spotted Sea-hare South half of Florida and the West Indies. 4 to 5 inches in length, characterized by its pale-yellow to yellowish- green color and the fairly large, usually irregular circles of violet-black scat- tered over the body. Common in some grassy localities. A. protea Rang of the West Indies is very similar, but the circles are more numerous, and often with smaller circles or large spots within the larger ones. Aplysia floridensis Pilsbry Sooty Sea-hare Lower Florida Keys. The West Indies? 4 inches in length. Color deep purple-black, the inside of the swimming 286 American Seashells lobes slightly lighter, and with blotches of black at the edges. Mantle purple- black, spotted irregularly with lighter purple. Uncommon? Subgenus Metaplysia Pilsbry 1951 Aplysia badistes Pilsbry 1951 Walking Sea-hare Biscayne Bay, Florida. And south? 2 to 4 inches in length. Mantle under the lobes with a large perforation. Sole of foot with a characteristic, muscular disk at each end. Exterior of animal dark-olive, indistinctly mottled with irregular spots of dusky buff, and having small, sparsely scattered, ragged black spots. Sole of foot yel- lowish olive. Found recently along the Venetian Causeway under rock ledges at low tide. (For details see Notulae Naturae, Philadelphia, no. 240, pp. 1 to 6, illustrated.) Genus Bursatella Blainville 1817 Bursatella leachi plei Rang Ragged Sea-hare West and northwest Florida and the West Indies. 4 inches in length, elongate-oval, plump, soft and flabby. Greenish gray to olive in color, sometimes with white flecks. Surface covered with nu- merous, ragged filaments. Shell absent in adults. Commonly found in grassy, mud-bottom areas at low tide. The east side of Sanibel Island is a good col- lecting spot. This is the only western Atlantic species known in this genus. Formerly placed in another genus, Notarchus Cuvier 1817. Family PLEUROBRANCHIDAE Genus Pleurobranchus Cuvier 1805 Subgenus Susania Gray 1857 Pleurobranchus atlanticus Abbott Atlantic Pleurobranch Figure 61 Southeast Florida (and the West Indies? ). 1% to 2 inches in length. Mantle with U-shaped notch in front where two tube-like rhinophores protrude up. Dorsum or back with numerous small rounded warts. Color yellowish orange with irregular splotches of deep maroon-brown. Largest warts translucent pale-yellow with a chocolate ring around the base. Some tipped with chalk-white. Foot pale-yellow to orang- PLEUROBRANCHIDAE 287 ish. Gill plume on right side of body, with 20 to 22 primary leaflets on each side, with a nodule on the main stem where they originate. Primary leaflets with 15 smaller leaflets, each of which has 5 to 10 microscopic plates. Shell Figure 61. Pleurobranchus atlanticus Abbott, 114 inches. 2 and 3, entire animal, 4, rhinophore; 5, cross-section of velum; 6, genitalia; 7, details of gill plume; 8, shell; 9, radula; 10, platelets in mandibles. (From R. T. Abbott 1949, Nautilus vol. 62.) small, calcareous, pinkish white, flat with a small spire, and located under the dorsum. Moderately common in shallow water in winter on Soldier Key, near Miami. Originally collected by F. M. Bayer, P. gardineri White is a synonym. 288 American Seashells Superfamily PY RAMIDELLACEA Family PY RAMIDELLIDAE This is a well-known family of very small gastropods which are ex- tremely baffling to novices attempting to identify any one of the several hun- dred so-called species. Even among the experts there is not always agreement on what constitutes a species, subgenus or genus in this group. It would be impossible to present in a book this size even an account of only the most common species. Those interested in delving into this interesting maze of species are referred to the works of Bartsch, W. H. Dall and K. Bush. The recent work of Fretter and Graham has shown that the Pyrams are ectoparasites, with each species feeding on a particular host, usually a tubico- lous polychaete worm or a bivalve mollusk. The Pyrams attach themselves ATLANTIC COAST PYRAMIDELLIDAE (FIGURE 62) (The names in parentheses are subgenera. Illustrations are from P. Bartsch, 1909, Proc. Boston Soc. Nat. Hist., vol. 34, no. 4. The measurements refer to the length of an average specimen). a, Odostomia (Chrysallida) willisi Bartsch. Willis’ Odostome. 3 mm.; milky white. Prince Edward Island, Canada. Uncommon. b, Turbonilla (Pyrgiscus) interrupta Totten. Interrupted Turbonille. 6 mm.,; pale waxy yellow. Casco Bay, Maine, to the West Indies. 2 to 107 fathoms. Common. ce, Turbonilla (Turbonilla) stricta Verrill. Varied Turbonille. 5 mm.; milky white. Massachusetts to North Carolina. 3 to 8 fathoms. Moderately com- mon. d, Turbonilla (Turbonilla) nivea Stimpson. Snowy Turbonille. 5 mm.; milky white. Maine to Connecticut. 40 to 400 fathoms. Uncommon. e, Pyramidella (Syrnola) fusca C. B. Adams. Brown Pyram. 6 mm.; light brown. Gulf of St. Lawrence to Florida. Common. f, Odostomia (Menestho) trifida Totten. Three-lined Odostome. 4 mm.; shiny white. Maine to New Jersey. Shore. Common. g, Odostomia (lolaea) hendersoni Bartsch. Henderson’s Odostome. 3 mm.; glossy white. Woods Hole, Massachusetts. Uncommon. h, Odostomia (Menestho) bisuturalis Say. Double-sutured Odostome. 5 mm.,; milky white. Nova Scotia to Delaware Bay. Shore to 2 fathoms. Common. i, Odostomia (Menestho)impressa Say. Impressed Odostome. 5 mm.; milky white. Massachusetts Bay to Gulf of Mexico. Common in shallow water. j, Odostomia (Chrysallida) seminuda C. B. Adams. Half-smooth Odostome. 4 mm.; whitish. Nova Scotia to Gulf of Mexico, Shore to 12 fathoms. Common. k, Odostomia (Odostomia) gibbosa Bush. Fat Odostome. 3 mm.; shiny, yellowish white. Maine to southern Massachusetts. Uncommon. (= modesta Bartsch, not Stimpson). PYRAMIDELLIDAE 289 to the host by means of an oral sucker, and pierce the body wall of the host with a buccal stylet. They suck the host’s blood by means of a buccal pump. Embryological and other data have shown that this family of mollusks is closely related to the tectibranch mollusks, rather than to the prosobranchs with which they have been formerly placed. (See Journal of the Marine Biological Assoc., vol. 28, pp. 493-532, 1949.) Genus Pyramidella Lamarck 1799 Pyramidella dolabrata Lamarck Giant Atlantic Pyram Plate 4q Bahamas and the West Indies. Florida Keys? %4 to 1 inch in length, solid and glossy smooth. Columella large, and with 2 or 3 strong, spiral plicae. Color opaque-white with 3 fine, spiral lines of brown, 1 of which is just above the suture. Common in the West Indies serene a sn : ms Ficure 62. Atlantic Coast Pyramidellidae, (See opposite page. ) PACIFIC COAST PYRAMIDELLIDAE (Ficure 63) (The names in parentheses are subgenera. “D. and B.” is the abbreviation for Dall and Bartsch 1909, Bull. 68, U. S. Nat. Mus., pls. 1-30, from which these drawings are taken. The measurements refer to the length of an average specimen.) a, Pyramidella (Lonchaeus) adamsi Carpenter. Adams’ Pyram. 15 mm. White to dark-brown, spotted or banded. San Pedro to Mexico. Common. b, Turbonilla (Chemmitzia) kelseyi D. and B. Kelsey’s Turbonille. 5 mm. Semi- transparent; ribs not on base of shell. Santa Barbara to Mexico. Shore to 30 fathoms. Moderately common. » Turbonilla (Turbonilla) acra D. and B. Acra Turbonille. to mm. Milk-white; 15 whorls; ribs extend down over the base of the shell. California. Rare. 5 Lurbonilla (Strioturbonilla) buttoni D. and B. Button’s Turbonille. 6 mm.; yellowish white; spire and base of shell with microscopic, wavy, spiral lines not shown in drawing). Southern California to Mexico. Shore to 25 fathoms. Common at many places. Turbonilla (Pyrgolampros) chocolata Carpenter. Chocolate Turbonille. 12 mm.; shiny, golden brown, with 2 or 3 spiral bands of lighter color. Monterey to San Diego. Shore to 25 fathoms. Uncommon. Turbonilla (Mormula) tridentata Carpenter. Three-toothed Turbonille. ro mm.; chestnut; obscurely banded; minutely reticulated; 3 folds on white columella. Monterey to Lower California. Shore to 4o fathoms. Common. Odostomia (Evalina) americana D. and B. American Odostome. 3 mm.; milky white. San Pedro to Lower California. Shore to 10 fathoms. Uncommon. Odostomia (Miralda) aepynota D. and B. Tower Odostome. 2 mm.; trans- lucent. San Pedro to Lower California. Shore to 12 fathoms. Uncommon. Odostomia (Odostomia) farella D. and B. Farelle Odostome. 3 mm.; white; fine growth lines only. Off Long Beach. Rare. Odostomia (Evalea) phanea D. and B. Phanea Odostome. 5 mm.; milky white. Monterey to San Diego. On rocks and abalones. Common. Turbonilla (Pyrgiscus) aragoni D. and B. Aragon Turbonille. 7 mm.; milky white; lower half of whorls brown, upper half flesh-colored. Base with 15 spiral lines. Monterey to Redondo Beach. 10 to 40 fathoms. Uncommon. Turbonilla (Bartschella) laminata Carpenter. Laminate Turbonille. 7 mm.; apex waxy yellow; last whorl brown; columella white. Redondo Beach to Lower California. Shore to 25 fathoms. Common. Odostomia (Ividella) pedroana D. and B. San Pedro Odostome. 7 mm.; choco- late-brown. San Pedro to Lower California. Shore to 12 fathoms. Common. Odostomia (Chrysallida) helga D. and B. Helga Odostome. 5 mm.; milky white. Redondo Beach to Gulf of California. Shore to 25 fathoms. Common. Odostomia (Ivara) terricula D. and B. Earth Odostome. 4 mm.; milky white. Monterey to Lower California. Shore to 25 fathoms. Common. Odostomia (lolaea) amianta D. and B. Pure Odostome. 5 mm.; yellowish white. San Mateo to Lower California. Shore to 75 fathoms. Common. Odostomia (Amaura) nota D. and B. Nota Odostome. 7 mm.,; light yellow. Santa Rosa Island to San Diego. Among weeds. Common. r, Odostomia (Evalea) donilla D. and B. Donille Odostome. 5 mm.; bluish white. Santa Monica to Lower California. Shore to 10 fathoms. Common. s, Odostomia (Menestho) fetella D. and B. Fetelle Odostome. 4 mm.; milky white. Santa Monica to Lower California. Shore to 6 feet. Common. t, Odostomia (Salasiella) laxa D. and B. Lax Odostome. 4 mm.; milky white. Catalina Island to Lower California. Shore to 70 fathoms. Common. ‘e) jo & — v a fe ee eee oe — “ clog ele eS 29) (See opposite page.) eve Nee. a at A\ a A iB PY RAMIDELLIDAE Ficure 63. Pacific Coast Pyramidellidae. 297 American Seashells and possibly present in the Lower Florida Keys. This species is a sand- dweller. Order PTEROPODA (Sea Butterflies or Pteropods) These small, pelagic gastropods are very abundant in the open seas in nearly every part of the world. They are occasionally washed ashore, but more commonly their shells are found in dredge hauls. The identification of pteropods is important to many types of oceanographic studies. There are two suborders, Thecosomata or those having shells, and the Gymnosomata or those without shells. We have omitted the latter group, and refer inter- ested workers to our bibliography. Every known American species (eastern Pacific and western Atlantic) of the shelled Thecosomata has been included and figured. Suborder THECOSOMATA Family SPIRATELLIDAE Genus Spiratella Blainville 1817 (Limacina) Spiratella helicina Phipps Helicid Pteropod Figure 64a Arctic Seas to the Gulf of Maine. Arctic Seas to northern California. Up to 8 mm. in length, spire short, shell wider than long. Surface with relatively large, axial threads. Adults (over 3 mm.) without an operculum. Abundant enough in the Arctic Seas to serve as an important source of food for certain whales. S. pacifica Dall is the same. Spiratella retroversa Fleming Retrovert Pteropod Figure 64c Arctic Seas to Cape Cod, Massachusetts. Up to 5 or 6 mm. in length, spire slightly elevated, umbilicus distinct, shell higher than wide. Entire surface covered with fine, spiral lines. ro whorls. Limacina balea Moller and Spirialis gouldi Stimpson are this species. Spiratella trochifornis Orbigny Trochiform Pteropod Figure 64e Cape Cod, Massachusetts, to Brazil. (N. Lat. 42° to S. Lat. 28°). 1 mm. in length, very close in characters, except shape, to S. retroversa, and thought by some workers to be a warm-water subspecies of that species. PERACEIDAE 293 Spiratella lesueuri Orbigny Lesueur’s Pteropod Figure 64b Cape Cod, Massachusetts, south to Brazil. Indo-Pacific. (N. Lat. 42° t075. Latcaom): 1.5 mm. in length, spire elevated somewhat; umbilicus distinct. Shell as long as wide. Spiral lines only around the umbilicus. Spiratella bulimoides Orbigny Bulimoid Pteropod Figure 64d New York to southern Brazil. (N. Lat. 39° to S. Lat. 40°). 2 mm. in length, spire high, shell twice as long as wide. Umbilicus very indistinct. Lip fragile and often broken. 6 to 7 whorls. Spiratella inflata Orbigny Planorbid Pteropod Figure 64h Cape Cod, Massachusetts, to Argentina. (N. Lat. 42° to S: Lats4o2)- 1.5 mm. in length, spire depressed, with the globose whorls in one plane to give a planorboid shape. Limacina scaphoidea Gould is this species. Family PERACLIDAE Genus Peracle Forbes 1844 Shell fragile, with sinistral or left-handed whorls (resembling the fresh- water pond snail, Physa); aperture very large and elongated; columella pro- longed into an elongate rostrum; no umbilicus. Operculum thin, paucispiral, sinistral and subcircular in outline. There are only two species in the genus. Peraclis Pelseneer is the same genus. Peracle reticulata Orbigny Reticulate Pteropod Figure 64g Worldwide, pelagic. (40° N. to 20° S.). 4 mm. in length, brownish yellow, sinistral and with 4 whorls. Suture deep. The surface exhibits a raised hexagonal reticulation, the sides of the hexagons bearing a regular row of minute teeth. P. physoides Forbes and P. clathrata Eyd. and Soul. are the same. Peracle bispinosa Pelseneer Two-spined Pteropod Figure 64f Atlantic, pelagic. (38° N. to 28° S.). 7 mm. in length, milky-white, similar to reticulata, but with a wide, 294 American Seashells shallow suture bearing axial ridges, and with the shoulder of the outer lip bearing a small, triangular projection. Uncommonly collected. Family CAVOLINIDAE Shell symmetrical (not coiled), fragile, white to brown, and of various shapes—needle-like, cylinder-shaped, flattened triangular or bulbous. Genus Creseis Rang 1828 Shell a long cone, almost circular in cross-section, needle-like. Creseis acicula Rang Straight Needle-pteropod Figure 64n Atlantic and Pacific, pelagic. (N. Lat. 48° to S. Lat. 40°). 20 to 33 mm. (about an inch) in length. A long, straight, slender cone tapering to a sharp point. Styliola vitrea Verrill and conica Esch. are this species. Creseis virgula Rang Curved Needle-pteropod Figure 64p Atlantic and Pacific, pelagic. (N. Lat. 41° to S. Lat. 35°). 8 to 10 mm. in length. A drawn-out, slender shell similar to acicula, but with its narrow end hooked to one side. The amount of bend of hook is variable. Hyalaea coniformis Orb. and Cleodora virgula Soul. and Eyd. are the same. Genus Styliola Lesueur 1825 Styliola subula Quoy and Gaimard Keeled Clio Figure 64-0 Worldwide in warm seas, pelagic. 10 mm. in length, conical, straight, considerably elongated. The surface is smooth, and with a dorsal groove not parallel to the axis of the shell, but slightly oblique, turning from left to right, with only the anterior extremity (which ends in a rostrum) in the median line. There is only one species in the genus and it is world-wide in distribution. Genus Hyalocylis Fol 1875 Hyalocylis striata Rang Striate Clio Figure 64q Worldwide in warm seas, pelagic. CAVOLINIDAE 295 8 mm. in length, conical, slightly compressed dorso-ventrally (oval in cross-section); apex slightly recurved dorsally; surface with transverse grooves; embryonic shell small, smooth, bulbous and separated from the main shell by a constriction, This is the only species in the genus, Genus Clio Linné 1767 Shell of a somewhat angular form, colorless, compressed dorso-ventrally, and with lateral keels. A cross-section of the anterior or open portion is thus always angular at the sides. There is generally a crest or ridge extending longitudinally along the back. Embryonic shell varies in form, but is always definitely separated from the rest of the shell. Cleodora Peron and Lesueur 1810 is the same genus. Clio pyramidata Linne Pyramid Clio Figure 64k Worldwide, pelagic. 16 to 21 mm. in length. No lateral keels on the posterior portion; with- out lateral spines. Lateral margins very divergent. No posterior transverse grooves. Dorsal ribs undivided. Common. C. Janceolata Lesueur and Cleo- dora exacuta Gould are this species. The shell exhibits considerable variation in form. Clio cuspidata Bosc Cuspidate Clio Figure 641 Atlantic and Indo-Pacific, pelagic. Without lateral keels on the posterior portion. Lateral spines very long. Common. Clio recurva Children Wavy Clio Figure 64] Atlantic and Indian Ocean. Warm water, pelagic. 1 inch in length, with lateral keels over its entire length. 3 dorsal ribs markedly projecting. A large, fragile, transparent and very exquisite species. This is C. balantium Rang. Clio polita Pelseneer Two-keeled Clio Figure 64] Atlantic, pelagic. With lateral keels over its entire length. Dorsal ribs very slightly pro- jecting. The posterior portion of the shell is narrow. C. falcata Pfeffer is the same species. 296 American Seashells Genus Cavolina Abildgaard 1791 Shell squat, bulbous, horny-brown in color, characterized by a much constricted aperture, which is, however, very broad transversely. Sides of shell often prolonged into spine-like projections. Cavolinia is an alternate, incorrect spelling, and Hyalaea Lamarck is a synonym of this genus. Long-snout Cavoline Figure 64v Cavolina longirostris Lesueur Worldwide, pelagic. (47° N. to 40° S.). 5 tog mm. in length. Dorsal lip with a thin margin. Posterior portion of the ventral lip markedly projecting laterally. Common. Hyalaea limbata Orb. and H. angulata Souleyet are synonyms. Gibbose Cavoline Cavolina gibbosa Rang Figure 64w Worldwide, pelagic. (43° N. to 38° S.). About 10 mm. in length. Dorsal lip with a thin margin. Shell without appreciable lateral points. Ventral lip not more developed than the dorsal. Ventral surface with an anterior transverse keel. Common. Three-toothed Cavoline Figure 64u Cavolina tridentata Forskal Worldwide, pelagic. (40° N. to 40° S.). 10 to 20 mm. in length. Dorsal lip with a thin margin. Ventral lip not more developed than the dorsal one. Shell without appreciable lateral points. The shell is as broad at the end of the lips as it is at the anterior end. C. gibbosa is narrower at the ends of the lips. Hyalaea affinis Orb. is merely a form of this species. C. telemus Linné might possibly be this species. Figure 64. The Pteropods or Sea-but- terflies of American Waters. a, Spira- tella helicina Phipps; b, S. lesueuri Orb.; c, S. retroversa Fleming; d, S. bulimoides Orb.; e, S. trochiformis Orb.; f, Peracle bispinosa Pelseneer; g, Peracle reticulata Orb.; h, Spiratella inflata Orb.; i, Clio cuspidata Bosc; j, Clio recurva Children; k, Clio pyramidata Linné; 1, Clio polita Pelseneer; m, Czvierina columnella Rang, n, Creseis acicula Rang, 0, Styliola sub- ula Q & G; p, Creseis virgula Rang; q, Hyalocylis striata Rang; r, Cavolina in- flexa Lesueur; s, Cavolina quadridentata Lesueur; t, C. trispinosa Lesueur; u, C. tridentata Forskal; v, C. longirostris Lesueur; w, C. gibbosa Rang; x, C. un- cinata Rang, sr. ait Se Hyon IGURE 64. Explanations on opposite page. 298 American Seashells Cavolina uncinata Rang Uncinate Cavoline Figure 64x Worldwide, pelagic. (40° N. to 40° S.). 6 to 7 mm. in length. Dorsal lip with a thin margin. Ventral lip not more developed than the dorsal one. Shell with distinct lateral points. Upper lip flattened posteriorly. C. wncinatiformis Pfeffer is a synonym. Cavolina inflexa Lesueur Inflexed Cavoline Figure 64r Atlantic and Indo-Pacific. (41° N. to 42° S.). 6 to 7 mm. in length, similar to uncinata, but the upper lip is directed straight forward, instead of flattened posteriorly; and the ventral side of the shell is weakly, instead of strongly, convex. C. Jabiata Orb., C. imitans Pfeffer and C. elongata Blainville are this species. Subgenus Diacria Gray 1842 Similar to Cavolina s.s., but the dorsal lip of the shell is thickened into a pad, and not thin as the true Cavoline is. Some workers use this as a genus. Cavolina trispinosa Lesueur Three-spined Cavoline Figure 64t Worldwide, pelagic. (60° N. to 41° S.). About 11 mm. in length. Dorsal lip thickened into a pad. Shell with a long lateral spine on each side, and a very long terminal one. Aperture scarcely discernible. Ventral side of shell very slightly convex. C. mucro- nata Q. and G., C. cuspidata Delle Chiaje and C. reeviana Dunker are this species. Very common. Cavolina quadridentata Lesueur Four-toothed Cavoline Figure 64s Worldwide, pelagic. (36° N. to 28° S.). 2 to 4mm. in length. Dorsal lip thickened into a pad. Without promi- nent lateral spines. Aperture well-developed. Ventral side greatly inflated. Upper lip longer than the bottom one. C. inermis Gould, C. minuta Sowerby, C. intermedia Sowerby and C. costata Pfeffer are synonyms. Quite common. Genus Cuvierina Boas 1886 Shell cylindrical, shaped somewhat like a fat cigar. Surface smooth. A cross-section is almost circular. Behind the aperture the shell is slightly con- DORIDAE 299 stricted. There is only one species in the genus. The genera Cuvieria Rang and Herse Gistel 1848 (non Oken 1815) are synonyms. Cuvierina columnella Rang Cigar Pteropod Figure 64m Worldwide, pelagic. (43° N. to 42° S.). 10 to 14 mm. in length. See generic description and figure. The shell varies somewhat in shape. C. oryza Benson, C. urceolaris Morch and can- cellata Pfeffer are the same. Common. Suborder GY MNOSOMATA Pteropods characterized by the absence of shell, pallial cavity and mantle-skirt; by the presence of a well-developed head, bearing two pairs of tentacles, of which the two posterior bear rudimentary eyes. Jaws and radula present. Found pelagic in all seas, and sometimes in great abundance. Rarely exceed one inch in length. They are carnivorous. Ascend to the surface at night, and sink to a lower level in the daytime. They are not treated in this book. The group contains such genera as Pneumodermopsis Bronn 1862, Pneumoderma Cuvier 1805 (= Pneumonoderma Agassiz), Cliopsis Troschel 1854 (=Clionopsis Bronn), Notobranchaea Pelseneer 1886, Clione Pallas 1774, Paedoclione Danforth 1907, Anopsia Gistel 1848 (= Halopsyche Bronn and Euribia Rang). Order NUDIBRANCHIA (Nudibranchs and Sea-slugs) Superfamily DORIDACEA Family DORIDIDAE Branchial plumes in an arc or circle usually joined together at their bases, usually retractile into a cavity. Rhinophores always with a perfoliate club. Pharyngeal bulb never suctorial. Genus Archidoris Bergh 1878 Body not hard, dorsum granular or tubular; tentacles short, thick, with an external, longitudinal sulcus. No labial armature. Branchial plumes not numerous, 3- to 4-pinnate. Center of radula naked, marginal teeth hooked and bearing minute denticles. Penis and vagina unarmed (without hooks). Archidoris monterey ensis Cooper Monterey Doris Plate 16h California. 1 to 2 inches in length. Rhinophore stalks conical, the clavus slightly 300 American Seashells dilated, conical, perfoliate with 24 to 30 leaves on each side. Each of the 7 branchial plumes large, spreading and 3- to 4-pinnate. Radula with 33 rows; center naked; with 42 to 49 strongly hooked, denticulate pleural teeth. Com- mon in tide pools. Subgenus Anisodoris Bergh 1898 Archidoris nobilis MacFarland Noble Pacific Doris Plate 16c California. 4 inches in length. Rhinophore stalk stout, conical, the clavus perfoli- ate, with about 24 leaves, and the stalk deeply retractile within low sheaths, the margins of which are tuberculate. Each of the 6 branchial plumes large and spreading, 3- to 4-pinnate. A thin, membrane-like expansion joins the bases of the plumes. Radula with 26 rows; center naked; with 55 to 62 strongly hooked pleural teeth. Moderately common in tide pools. Genus Discodoris Bergh 1898 Body rather soft, oval in outline; branchial aperture slightly crenulate, stellate or bilabiate; anterior margin of the foot bilabiate, the upper lip more or less notched. Discodoris heathi MacFarland Heath’s Doris Plate 161 California. 1 inch in length. Mantle thick, densely spiculate. Rhinophores cylindro- conical, the stalk stout, the clavus with 10 to 15 leaves, and wholly retrac- tile. Each of the 8 to 10 branchial plumes are tripinnate. Radula colorless, with 20 rows of teeth; center naked. 36 to 42 strongly hooked pleural teeth. Rather rare in rock pools in the summer. Genus Rostanga Bergh 1879 Back covered with minute, spiculose or stiff papillae; branchiae of simple-pinnate leaves. Rostanga pulchra MacFarland MacFarland’s Pretty Doris Plate 16g California. %4 inch in length. Rhinophores short, stout, translucent-pink, stalk stout, prolonged beyond the 20- to 24-leaved clavus as a blunt, cylindrical process which is % the length of the entire rhinophore. ro to 12 erect, sepa- SS —_—-- -— DORIDAE 301 rate, retractile branchial plumes. Radula with 65 to 80 rows of 80 denticu- late pleural teeth. Lives on red sponges. The egg-ribbon is orange-red and often laid on the sponge. Common. Genus Diaulula Bergh 1880 Body fairly soft; back silky finish; branchial aperture round and crenu- late; branchial plumes tripinnate. Diaulula sandiegensis Cooper San Diego Doris Plate 16d Alaska to San Diego, California. 2 to 3 inches in length. Body soft; back velvety. Rings of black varying greatly in number and clarity (2 or 3 to 30). Rhinophores conical, the clavus with 20 to 30 leaves, deeply retractile into a conspicuous sheath with a crenulate margin. 6 branchial plumes tripinnate. Radula broad, with 19 to 22 rows, each row with 26 to 30 falcate teeth on each side of the naked center. Moderately common in rock pools of the fucoid zone at all seasons. The broad, white, spiral egg bands are commonly laid from June to August. Genus Aldisa Bergh 1878 Aldisa sanguinea Cooper Blood-red Doris Monterey Bay to Point Lobos, California. ¥ inch in length. In form, superficially resembling our figure of Archi- doris montereyensis (pl. 16h), but bright-scarlet to light-red, sprinkled every- where with very minute, black spots. Characterized by 2 or 3 very large, oval spots of black on the back. Rhinophores similar in form, with 12 to 15 leaves in the clavus. Branchial plumes 8 to 10, simply or irregularly bi- pinnate. Radula with 70 rows of teeth, each row with 70 to roo teeth which are long, slender and with small, swollen bases. Not uncommon in rock pools, Subfamily CADLININAE Labial armature lamelliform, almost annulate, of extremely small hooks. Middle of radula with a denticulated tooth. External margin of pleural teeth serrate. Genus Cadlina Bergh 1879 Characters of the subfamily. The glans penis is armed with a series of hooks. Usually the animal is from 1 to 2 inches in length. 302 American Seashells Cadlina laevis Linné White Atlantic Doris Arctic Seas to Massachusetts. Europe. 1 inch in length, similar to our figure of A. nobilis (pl. 16c), but a pure, Waxy, semi-transparent white. Back with numerous very small, obtuse, opaque-white tubercles. An irregular row of white or sulfur-yellow, angu- lar spots located down each side near the margin of the back. Rhinophores opaque-white or yellowish, with 12 or 13 leaflets, surmounted by a short, blunt point. Branchial plumes of 5 imperfectly tripinnate, transparent white plumes. Radula with 50 to 70 rows of teeth. 29 to 30 pleural teeth on each side of the central tooth, the latter with 3 to 4 denticles on each side of the center hook. Locally uncommon. C. repanda Alder and Hancock, C. obve- lata Miller and C. planulata Gould are this species. Cadlina flavomaculata MacFarland Yellow-spotted Doris Pacific Grove to San Diego, California. % inch in length. Characterized by the 2 rows of lemon-yellow spots borne upon low tubercles. Rhinophores with 10 to 12 leaves in its club. Branchial plumes small, 10 to 11, either simple pinnate or bipinnate. Radula with about 77 rows of teeth, with 23 pleural teeth on each side of the central tooth which has 4 to 6 equal-sized denticles. All times of the year in small numbers in rocky tide pools. Cadlina marginata MacFarland Yellow-rimmed Doris British Columbia to Monterey Bay, California. 17 inches in length, similar to our figure of A. nobilis (pl. 16c), but covered everywhere with low, yellow-tipped tubercles surrounded by a nar- row ring of white and forming the center of a clearly marked polygonal area. Ground color a translucent yellowish white. There is a distinct narrow band of lemon-yellow around the margins of the mantle and the lateral and posterior edges of the foot. Rhinophores with 16 to 18 leaves in the clavus. Branchial plumes 6, bipinnate, sheath with yellow-tipped tubercles on the margin. go rows of teeth, with about 47 pleural teeth on each side of the central tooth which has 4 to 6 even-sized denticles. Not uncommon in rock pools. Subfamily GLOSSODORIDINAE Brilliantly blue-colored; back smooth, body elongate. Labial armature strong, of very minute hooks. Center of radula very narrow, often with DENDRODORIDIDAE 303 minute, compressed spurious teeth. Penis unarmed. Chromodoris Alder and Hancock is a synonym of the following genus. Genus Glossodoris Ehrenberg 1831 Glossodoris porterae Cockerell Porter’s Blue Doris ; : k Plate 16] Monterey to San Diego, California. ¥% inch in length, characterized by its deep ultramarine blue (dissolves out at death) and by the two orange stripes. Foot without orange marks. Fairly common in rocky tide pools. This might be the young or a form of the next species. Glossodoris californiensis Bergh Californian Blue Doris Monterey to San Diego, California. 2 inches in length. Like G. porterae, but with numerous, bright, orange, oblong spots in two rows on the mantle, another row down each side of the foot, and a group of round spots on the anterior end. Common in tide pools. G. universitatis Ckll. is this species. Glossodoris macfarlandi Cockerell MacFarland’s Blue Doris La Jolla to San Pedro, California. ¥% inch in length, like a small porterae, but with a ground color of red- dish purple (not dissolving out at death); mantle with a yellow-orange mar- gin and 3 longitudinal yellow stripes. End of foot with an orange stripe. Rare. Family DENDRODORIDIDAE Body soft, Doris-shaped. Pharyngeal bulb and elongated sucking tube, destitute of mandibles and radulae. Penis armed with a series of hooks. Doriopsis Pease is a synonym of the following genus. Genus Dendrodoris Ehrenberg 1831 Dendrodoris fulva MacFarland Common Yellow Doris California. 2 inches in length. Back soft, with low, papilla-like elevations tipped with white. Rhinophores with 18 to 20 leaves in the clavus which is % the 304 American Seashells length of the entire rhinophore. It is completely retractile. 5 branchial plumes are tripinnate. No mandibles or radula. One of the commonest Pa- cific Coast species. In tide pools at all times of the year, especially common in summer. Coiled egg band 1s yellow. Family POLYCERIDAE Body limaciform (slug-like); branchial plumes not retractile. Genus Laila MacFarland 1905 Laila cockerelli MacFarland Laila Doris Plate 16) Monterey to San Diego, California. %4 inch in length. Rhinophores with 13 leaves in the clavus. 5 branchial plumes tripinnate, non-retractile into the cavity. 76 to 82 rows of radula; center with a series of rectangular, flattened plates; on the side are 2 pleural teeth, then 10 to 13 closely set pavement-like uncinal teeth. Glans penis long, armed with 10 to 12 irregular rows of minute, thorn-like hooks. Not very common. Found under shelving rocks in tide pools, Genus Triopha Bergh 1880 Triopha carpenteri Stearns Carpenter’s Doris Plate 16k Monterey to Point Lobos, California. 1 inch in length. Rhinophores with 20 to 30 leaves in the club. 5 branchial plumes, large, tripinnate. 30 to 33 rows of radulae, with 4 teeth on the center part (the rhachis); pleural teeth 9 to 18, strongly hooked. Un- cinal teeth 9 to 18, quadrangular in outline. Very common in rock pools. Triopha maculata MacFarland Maculated Doris Plate 16f Monterey to Point Lobos, California. 1 inch in length. Rhinophore stalk and club same length, the latter with 18 leaves. Branchial plumes 5, tripinnate 14 rows of teeth, each row with 4 flattened plates, 4 to 5 pleurals, and 7 to 8 uncinal teeth. Blunt glans penis armed with minute hooks. Abundant in summer in rock pools, in winter un- common. Triopha grandis MacFarland MacFarland’s Grand Doris Plate 16b California. ONCHIDORIDAE 305 2 to 3 inches in length. With 8 to 12 tuberculate processes in front of head, and 6 to 7 more down the sides of the back. Back yellowish-brown, often flecked with bluish spots. Tips of yellow processes, tip of tail and tips of branchial plumes with yellowish red. Rhinophores set in conspicuous sheaths, club yellow with 20 leaves. Branchial plumes 5, bushy, tri- and quadri-pinnate. 18 rows of radular teeth; 4 centrals, 8 pleurals and 8 uncinal teeth, Found on brown kelp, Fairly common, Genus Polycera Cuvier 1817 Frontal margin with finger-like processes. Finger-like processes border- ing branchial plumes. Center of radula naked, flanked by 2 lateral teeth and several uncini. Polycera atra MacFarland Orange-spiked Doris Plate 16e Monterey to San Diego, California. % to 1 inch in length. The blue-black lines shown in our figure are usually thinner and less conspicuous. 8 gill plumes. Common on brown algae. g to 10 rows of radular teeth, dark-amber; 2 pleurals, 3 to 4 uncinal teeth. Family ONCHIDORIDAE Genus Acanthodoris Gray 1850 Body Dorid-like with a furry back. Labial disk armed with minute hooks. Center of radula naked; first pleural tooth large, external pleurals 4 to 8, small. Glans penis armed. Vagina very long. Acanthodoris pilosa Abildgard Pilose Doris Plate 15b Arctic Seas to New Haven, Connecticut. Alaska. ¥% to 1% inches in length. Semi-transparent. Color variable, ranging from pure white to yellowish white, canary-yellow, yellowish brown, gray- speckled, purple-brown and black. Back covered with soft, slender, conical, pointed papillae, which give it a hairy appearance. Rhinophores long, its club bent backwards and with 19 to 20 leaves. Sheath denticulate. Branchial plumes 7 to 9, large and spreading, tripinnate, transparent. A number of color forms have been described from Alaska by Bergh and from New Eng- land by A. E. Verrill. Radula with about 27 rows. No central tooth, 4 pleurals on each side. Moderately common at low tide, sometimes found out of water, 306 American Seashells Acanthodoris brunnea MacFarland Pacific Brown Doris Monterey Harbor, California. %4 inch in length, somewhat like our figure of A. pilosa (pl. 15b). Some- what broader at the anterior end. Brown tubercles on back rounder, fewer, not as pointed. Back brown with flecks of black and with small spots of lemon-yellow between the tubercles. Rhinophores deep blue-black, tipped with yellowish white. Club with 20 to 28 obliquely slanting leaves. 7 bran- chial plumes, wide-spreading, bipinnate. About 10 tubercles are included within the rosette, 4 or 5 of them large and enclosing the anal papilla. An- terior margin of back is yellow. 24 to 28 rows of radular teeth. No centrals. First pleural large, with 14 to 19 denticles on the inner border. 6 to 7 other smaller pleural teeth. Dredged 30 to 60 fathoms. Genus Adalaria Bergh 1878 Adalaria proxima Alder and Hancock Yellow False Doris Plate 151 Arctic Seas to Eastport, Maine. Europe. % inch in length; deep yellow, white or yellow-orange. Back covered with stout, subclavate, or elliptical bluntly pointed tubercles, set at a little distance apart, and mixed with smaller ones. Calcareous spicules appear through the skin, radiating from the tubercles. Rhinophores with 15 leaves reaching almost to the base. Margin of sheath smooth. Branchial plumes rr. 40 rows of radular teeth. No central tooth. First pleural large, sickle-shaped, other 11 small and plate-like. Uncommon (?) in New England. Family OKENIIDAE Genus Ancula Loven 1846 Ancula cristata Alder Atlantic Ancula Plate 15f Arctic Seas to Massachusetts. Europe. % inch in length, of a transparent watery white, smooth. Rhinophores with 8 to 10 leaves. 3 branchial plumes, tripinnate. Labial armature of rows of imbricated hooks. Radula narrow, center naked, 25 to 27 rows of teeth; inner pleural large, denticulate on the inner margin. Outer pleural tooth small, smooth. A. sulphurea Stimpson is probably this species. On the north- west coast of Florida there is a Polycera (hummi Abbott) which superficially resembles this species in external features, but its radula indicates its true relationships. DENDRONOTIDAE 307 Ancula pacifica MacFarland Pacific Ancula California. ¥% inch in length, very similar to our figure of A. cristata (pl. 15f). Color translucent-yellow with 3 narrow, orange lines on the anterior half of the back, and one down the center of the back half. Rhinophores with 9 yellowish leaves. 3 branchial plumes. 4 (not 6) finger-like processes on each side of the plumes. 35 rows of teeth in the radula. Center with a small quadrangular plate, flanked by one large and one small pleural tooth. Genus Hopkinsia MacFarland 1905 Hopkinsia rosacea MacFarland Hopkins’ Doris Plate 16a Monterey to San Pedro, California. 1 inch in length. Rhinophores long and tapering, the anterior side smooth along the entire length. %4 of the posterior side bears about 20 pairs of oblique plates. Branchial plumes 7 to 14, entirely narrow and naked. 1 large pleural tooth on each side, flanked by a tiny, triangular pleural. Spiral egg ribbon rosy. Moderately common at all times of year under shelving rock between tide marks. Superfamily AEOLIDIACEA Family DENDRONOTIDAE Genus Dendronotus Alder and Hancock 1845 Body compressed; 2 tentacles laminated, with arborescent sheaths; nu- merous branchiae ramose. Arrow-shaped central tooth with a denticulate margin; about 9 elongate laterals on each side. About 40 rows of teeth. Dendronotus frondosus Ascanius Frond Eolis Plate 15e Arctic Seas to Rhode Island. Alaska to Vancouver Island. 2 inches in length. Rhinophores with 5 or 6 large leaves, interspaced by about 15 smaller ones. Other characters as shown in our figure and the generic descriptions. D. arborescens Miiller is this species. Common from shore to 60 fathoms. Dendronotus giganteus O’Donoghue Giant Frond Eolis Northwest United States. 5 to 8 inches in length. Similar to our figure of frondosus. 16 to 18 308 American Seashells leaves, all told, in the club of the rhinophore. Distinguished from frondosus by the 3 to 5 small but well-marked dendriform papillae on the posterior edge of the rhinophore sheath. Usually dredged down to 25 fathoms. Prob- ably the largest of the American nudibranchs. Family SCYLLAEIDAE Genus Scyllaea Linne 1758 Scyllaea pelagica Linné Sargassum Nudibranch Southeast United States. Other warm seas. 1 to 2 inches in length. Translucent cream-brown to orange-brown. With numerous flecks of red-brown. Body elongate. Oral tentacles absent. Two slender long rhinophores. Sides of body with 2 pairs of large, club- like, foliaceous gill plumes or cerata. Common in floating sargassum weed in the Gulf Stream. Family AEOLIDIIDAE Genus Aeolidia Cuvier 1798 Body depressed, rather broad; branchiae a little flattened, set in numer- ous, Close, transverse rows; 4 tentacles simple; foot broad, anterior angies acute. Radula of a single, broad, pectinate plate. Aeolidia papillosa Linné Papillose Eolis Plate 15g Arctic Seas to Rhode Island. Europe. Arctic Seas to Santa Barbara, California. 1 to 3 inches in length. Color variable: brown, gray or yellowish, always more or less spotted and freckled with lilac, gray or brown and opaque-white. Number of papillae fewer in young specimens. 30 rows in radula of a single, broad, arched tooth bearing about 46 denticles. Family TERGIPEDIDAE Genus Catriona Winckworth 1941 (Cratena of authors) Catriona aurantia Alder and Hancock Orange-tipped Eolis Plate 15) Arctic Seas to Connecticut. Europe. % inch in length. Branchiae numerous, occurring in ro or 11 close, transverse rows, anteriorly with 5 to 6 papillae per row, posteriorly with 2 FLABELLINIDAE 309 to 4. Radula of 80 plates which are horseshoe-shaped and with 6 strong, straight denticles. Not too common. C. aurantiaca A. and H. is the same species. Genus Tergipes Cuvier 1805 Body slender; tentacles simple, the oral pair very short. Branchiae not very numerous, fusiform, inflated, set in a single series on each side of the back; foot narrow, anterior angles rounded. Egg mass kidney-shaped. Rad- ula with a single row of plates, each with a stout central denticle and numer- ous delicate marginal denticles. Tergipes despectus Johnston Johnston’s Balloon FEolis Plate 15d Arctic Seas to New York. Europe. ¥ inch in length, characters as shown in our figure and in the generic description. Gregarious on hydroids. Shore to 8 fathoms. Common (?). Family GLAUCIDAE Genus Glaucus Forster 1777 Glaucus marinus Du Pont 1763 Blue Glaucus Worldwide, pelagic in warm waters. 2 inches in length, body elongate, head small. Tentacles and rhinophores very small. 4 clumps of vivid-blue frills on each side of the body. Dorsal side smooth, striped with dark-blue, light-blue and white. Underside pale grayish blue. With strong jaws and a radula of a center row of about 10 denticulated teeth. Moderately common at certain seasons. Washed ashore with Janthina, the Purple Sea-snail. G. atlanticus Forster, G. radiata Gmelin and G, forsteri Lamarck are all this species. Family FLABELLINIDAE Genus Eubranchus Forbes 1838 Resembling Tergipes. Radula with central plate with several stout denticles. A triangular lateral tooth is on each side of the central plate. Eubranchus exiguus Alder and Hancock Dwarf Balloon Eolis Plate 15c Arctic Seas to Boston, Massachusetts. Europe. ¥ inch in length, characters as shown in our figure and the generic description. Seasonally uncommon. 310 American Seashells Eubranchus pallidus Alder and Hancock Painted Balloon Eolis Plate 1sh Arctic Seas to Boston, Massachusetts. Europe. % inch in length, characters as shown in our figure and the generic description. Uncommon (?). Genus Coryphella Gray 1850 Branchiae numerous, clustered, elongate or fusiform. Foot narrow, with the anterior angles much produced. Radula with a single longitudinal series of central teeth which bear a large central denticle and several marginal denticles. There is a denticulated lateral tooth on each side of the central. Coryphella rufibranchialis Johnston Red-fingered Eolis Plate 15a Arctic Seas to New York. Europe. 1 inch in length, characters as shown in figure and in the generic de- scription. Common (?) in New England. Subclass PULMONATA Order BASOMMATOPHORA Family SIPHONARIIDAE Genus Siphonaria Sowerby 1824 Shells closely resembling the true limpets, Acmaea, but at once distin- guished by the nature of the muscle scars on the inside. In both, the long, narrow scar is horseshoe-shaped, but in Siphonaria the gap between the ends is located on one side of the shell, while in Aczzaea it is located at the front end. In some Siphonaria, the area near the gap is trough-shaped. These are air-breathers and are more closely related to the land garden snails than to the gill-bearing, water-breathing limpets. Siphonaria pectinata Linné Striped False Limpet Figure 65b Eastern Florida, Texas, Mexico and St. Thomas. 1 inch in length, rather high, with an elliptical base. Exterior with numerous, fine, radial threads or rather smoothish. Color whitish with nu- merous, brown, bifurcating, radial lines. Interior glossy, similarly striped. Center cream to brown. Muscle scar with 3 swellings, the gap occurring be- tween the two at the side. Do not confuse with Acmaea leucopleura which commonly has a blackish owl-shaped figure inside. Common along the shores on rocks. This is S, naufragum Stearns and S. lineolata Orbigny. eee | | SIPHONARIIDAE ant Ficure 65. Atlantic Coast False Limpets. Side and interior views of a, Siphonaria alternata Say; b, S. pectinata Linné, Natural size. Siphonaria alternata Say Say’s False Limpet Figure 65a Southeast Florida (and Sarasota), the Bahamas and Bermuda. % to %4 inch in length, with about 20 to 25 small, white, radial ribs between which are smaller riblets. Background gray to cream. Interior glossy-tan, sometimes striped or mottled with dark-brown. Fairly common on rocks near the shore line. CReeall nh Re Va Coat-of-Mails and Other Chitons Clas AMPHINEURA Order LEPIDOPLEURIDA Family LEPIDOPLEURIDAE Genus Lepidopleurus Risso 1826 Lepidopleurus cancellatus Sowerby Arctic Cancellate Chiton Greenland to the Gulf of Maine. Bering Sea to Oregon. % inch in length, arched; color of exterior an orange-gray to whitish gray; interior white. Anterior valve microscopically granulated in radial rows. Central areas of the intermediate valves very finely granulated with densely placed, round pimples. Posterior valve with a smooth, slightly ele- vated central apex. Girdle narrow, same color as the valves and densely packed with tiny, split-pea scales. Some scales are commonly club-shaped, especially at the margins of the girdle, or sometimes so irregular and crowded as to give the appearance of fine moss. Moderately common on gravel bottoms from 20 to 100 fathoms. Key to the Small Red Chitons (1% to 1 inch) Girdle naked: Valves dull, color pattern maculated . . YTonicella marmorea Fabr. Valves glossy, with bright, black and white lines ot, 335 ye ee ee eee on Tonicella lineata Wood Girdle with scales: With overlapping, split-pea scales . . Lepidopleurus cancellatus Sby. 312 LERPIDOGHITFONIDAE 515 With tiny, granular scales: Interior of valves bright pnk . . . ~~ Ischnochiton ruber L. Interior of valves white . . . .... Ischnochiton albus L. Order CHITONIDA Family LEPIDOCHITONIDAE Genus Tonicella Carpenter 1873 Tonicella marmorea Fabricius Mottled Red Chiton Greenland to Massachusetts. Japan and the Aleutian Islands. About 1 inch in length, oblong to oval, elevated and rather acutely angular. Colored a light-tan over which is a heavy suffusion of dark-red maculations and specks. Upper surface appears smooth, although under high magnification it is seen to be granulated. Lateral areas of intermediate valves not very distinctly outlined. Interior of valves tinted with rose. Pos- terior valve with 8 to 9 slits. Girdle is leathery and without scales or bristles. Superficially this species resembles Ischnochiton ruber which, however, has scales on its girdle, Common from 1 to 50 fathoms. Tonicella lineata Wood Lined Red Chiton Japan to the Aleutians to San Diego, California. About an inch in length, similar to T. marmorea, but with its valves smooth and shiny, and it is brightly painted with black-brown lines bordered with white which run obliquely backwards on the intermediate valves. The end valves have these same color lines concentrically arranged. Common on the rocky shores of Alaska. The young live in waters off the shore from 10 to 30 fathoms, but as they mature they migrate toward shore. Genus Lepidochitona Gray 1821 Subgenus Cyanoplax Pilsbry 1892 Lepidochitona dentiens Gould Gould’s Baby Chiton Alaska to Monterey County, California. ¥, inch or slightly more in length, oval, slightly elevated. Color tawny, olivaceous, slaty or brownish, usually covered with specklings of a darker hue. Upper surface of valves covered with microscopic, sharp granulations which are rarely aligned in any direction. Lateral areas may be slightly raised, and may be bounded in front by a very low rib. The apex of the posterior valve is near the center and is raised; behind the apex, the valve 314 American Seashells is concave. Girdle very narrow, same color as the valves, and with very minute, gritty granules. L. (C.) dentiens is a common intertidal form found north of Monterey County, California. It is replaced to the south by the very similar and common L. (L.) keepiana Berry (Keep’s Baby Chiton). In the former, the insertion teeth are prominently developed, their bounding slits in general widely V-shaped, and the teeth of the posterior valve very acute on the sides; the eaves are wide and conspicuously porous or “spongy.” In the latter species, there are numerous short, zarrowly slitted teeth in the terminal valves, and extremely thin, narrow, less openly porous eaves. (See S. S. Berry, 1948, Leaflets in Malacology, vol. 1, no. 4.) Lepidochitona hartwegi Carpenter Hartweg’s Baby Chiton Washington to Lower California. 1 to 1% inches in length, oval, rather flattened. Similarly colored to L. dentiens. Girdle narrow and finely granulated. Sculpture of the end valves and the lateral areas of the middle valves differs from the microscopic granu- lations of dentiens in bearing easily seen, but very tiny, warts. It also differs in having the area behind the apex of the posterior valve convex instead of concave. Moderately common in intertidal areas. Genus Nuttallina Carpenter 1879 Nuttallina californica Reeve Californian Nuttall Chiton Vancouver Island to San Diego, California. About 1 inch in length, almost 3 times as long as wide. Color dark- brown to olive-brown. Upper surface of valves finely granulated and with a shallow furrow on each side of the smooth dorsal ridge. Apex, or mucro, of posterior valve so far back that it extends beyond the posterior margin of the eaves. Interior of valves bluish. Posterior valve about as wide as long and with 8 to 9g slits. Girdle with short, rigid spinelets mostly brown in color and with a few white ones intermingled. The girdle looks mossy. Moderately common. Nuttallina scabra Reeve Rough Nuttall Chiton San Diego to Lower California. Very similar to N. californica, but the posterior valve twice as wide as long. Color of valves lighter. Girdle spines much less numerous. This is Carpenter’s Acanthopleura flexa. MOPALIIDAE 315 Family MOPALIIDAE Genus Mopalia Gray 1847 Mopalia ciliata Sowerby Hairy Mopalia Alaska to Monterey, California. 1 to 1% inches in length, oblong, usually colored with splotches of black and emerald-green, although sometimes having cream-orange bands on the sides of the valves. Sometimes grayish green with grayish black or white mottlings. Girdle colored yellowish brown to blackish brown. Valves slightly beaked; lateral area separated from the central area by a prominent, raised row of beads. Central areas with many coarse, wavy, longitudinal riblets, which are sometimes pitted between. Lateral areas coarsely granu- lated or wrinkled. Posterior valve small, with a deep slit on each side and a broad, deep notch at the very posterior end. Girdle fairly wide, generally notched at the posterior end and clothed with curly, strap-like brown hairs between which are much smaller, glassy white hairs or spicules. Interior of valves greenish white. Anterior valve granulated and with 8 to 9 coarse, raised rays of beads. A common intertidal species. The subspecies wosnes- senski Middendorff (Alaska to Puget Sound) is supposed to be without the tiny white spicules in the girdle. Mopalia muscosa Gould Mossy Mopalia Alaska to Lower California. 1 to 2 inches in length, oblong to oval. Very similar to M. ciliata, but differing in having a very shallow and small notch at the very posterior end. Color usually a dull-brown, blackish olive or grayish. Interior of valves blue-green, rarely stained with pinkish. Girdle with stiff hairs resem- bling a fringe of moss. The following species have been considered by some workers as varieties of #uscosa, and perhaps with some justification: lignosa Gould, hindsi Reeve, acuta Carpenter, the latter having also been named plumosa and fissa by Carpenter. A common intertidal species. Mopalia lignosa Gould Woody Mopalia Alaska to Lower California. 1 to 2% inches in length, oblong. Color a grayish green or blackish green, rarely with whitish cream and brown, feathery markings. The sculp- turing on the valves is very delicate and may consist only of numerous small pittings near the center. Concentric growth lines in smoother specimens are quite easily seen. Radial ribs absent on the end valves. Girdle solid or macu- 316 American Seashells lated with browns and yellows. Strap-like, brown hairs not numerous. In- terior of valves greenish white to white. Moderately common. Mopalia hindsi Reeve Hinds’ Mopalia Alaska to the Gulf of California. 2 to 3 inches in length, oblong, flattened and resembling M. ciliata Sowerby, but generally smoother. Girdle brown, rather thin and fairly wide, and almost naked except for a few short hairs. Interior of valves white with short crimson rays under the beaks. Moderately common. Genus Placiphorella Dall 1878 Placiphorella velata Pilsbry Veiled Pacific Chiton Figure 66a Monterey, California, to Lower California. 1 to 2 inches in length, readily recognized by its flat, oval shape and wide girdle which is very broad in front. There are a few hairs on the girdle which, if viewed under a lens, will be seen to be covered by a coat of diamond-shaped scales. Girdle reddish yellow. Valves colored a dull olivaceous brown with streaks of buff, blue, pink or chestnut. Interior of valves white with a slight bluish tint. Posterior valve with 1 to 2 slits and with very large sutural plates. Fairly common intertidally. Genus Katharina Gray 1847 Katharina tunicata Wood Black Katy Chiton Figure 66b Aleutian Islands to southern California. 2 to 3 inches in length, oblong and elevated. Characterized by its shiny, naked, black girdle which covers 7% of each gray valve. Valves usually eroded. Anterior valve densely punctate. Interior of valves white. Foot salmon to reddish. Very common between tides, especially in the north. Genus Symmetrogephyrus Middendorft 1847 (Amicula Gray 1847, not 1842) Symmetrogephyrus vestitus Broderip and Sowerby Concealed Arctic Chiton Figure 66c Arctic Seas to Massachusetts Bay. Arctic Seas to the Aleutian Islands. 1 to 2 inches in length, oval, rather elevated. Valves covered with a thin, smooth, brown girdle except for a small, heart-shaped exposure at the CREEROPLACIDAE s17 center of each valve. Girdle may have widely scattered tufts of hair. In- terior of valves white. Common from 5 to 30 fathoms. S. pallasi Middendorff (Concealed Pacific Chiton) is very similar to vestitus, but the girdle is much thicker and the bunches of reddish hairs more numerous. Uncommon from 3 to 10 fathoms. oo i S a 7 ‘ ae |) A | ; Q 13 ae me Figure 66. Pacific Coast chitons. a, Placiphorella velata Pilsbry, 1 to 2 inches (California); b, Katharina tunicata Wood, 2 to 3 inches (Pacific Coast); ¢, Sym- metrogephyrus vestitus Brod. and Sby., 1 to 2 inches (Arctic waters to Massa- chusetts and Alaska); d, Amzicula stelleri Midd., 6 to 12 inches (Pacific Coast), showing position of the rst and 7th valves only. Genus Ceratozona Dall 1882 Ceratozona rugosa Sowerby Rough Girdled Chiton Figure 67a East Florida to the West Indies. 1 to 2 inches in length, oblong, slightly beaked. Surface commonly eroded, whitish gray with blue-green to moss-green mottlings on the sides of the calves. Surface roughly sculptured. Anterior valve with 1o to 11 strong, rugose, radiating ribs. Lateral areas bounded in front and behind by a large, rugose rib. Central area with low, rough, longitudinal ribs. In- terior of valves bluish green. Girdle leathery, yellowish brown and with numerous, yellowish brown clusters of strap-like hairs. Posterior valve rather small and with 8 to 10 slits. 35 to 36 gill lamellae. The gills extend the length of the foot, but do not go as far as the posterior end. Very common, especially in the Greater Antilles. Family CRY PTOPLACIDAE Genus Cryptoconchus Burrow 1815 Cryptoconchus floridanus Dall White-barred Chiton Figure 67b Southeast Florida to Puerto Rico. Rarely over an inch in length, long and narrow, and characterized by its thin, black, naked girdle which extends on to the valves except over the narrow, beaded dorsal area. These exposed bands in the valves make 318 American Seashells it appear as if a streak of white paint had been applied along the top of the | animal. The side of the girdle at each valve-suture has a minute pore bearing short bristles, but these 2 features are commonly difficult to see. A variety is found with a brown-colored girdle. 16 gill lamellae. They begin halfway back along the side of the foot. Uncommon. Genus Acanthochitona Gray 1821 Acanthochitona spiculosa Reeve Glass-haired Chiton Southeast Florida and the West Indies. 1 to 1% inches in length, elongate, with the girdle covering most of the valves. There are 4 clumps of long, glassy bristles near the anterior valve and one on each side of the other valves. The clumps are set in cup-like collars of the girdle skin. End valves and lateral areas of middle valves cov- ered with tiny, round, sharply raised pustules. The dorsal, longitudinal ridge is raised, narrow, distinct and smoothish except for microscopic pin- points. Lower edge of girdle with a dense fringe of brown or bluish bristles. 32 gill lamellae. The gills begin about 4% back along the side of the foot and do not extend quite so far back as the posterior mantle margin. A moderately common species in shallow water. A. astriger Reeve is the same species. Acanthochitona py gmaea Pilsbry Dwarf Glass-haired Chiton West Coast of Florida to the West Indies. % to % inch in length, moderately elongate and colored cream, green, brown or variegated with these colors. Similar to A. spiculosa, but smaller, and with its dorsal ridge triangular, less elevated and cut by longitudinal grooves. The pustules on the lateral areas and the end valves are round or oval. The clumps of bristles are the same. Not uncommonly found among rocks and dead shells at low tide. Acanthochitona balesae Pilsbry 1940 from the Lower Keys is very elongate, only ’% inch in length; the pustules on the lateral areas are pro- portionately larger and fewer, and the dorsal ridge is rounded and covered with small, granulose pustules. Rare at Bonefish Key, Florida. Genus Amicula Gray 1842 (Cryptochiton Middendorff 1847) Amicula stelleri Middendorft Giant Pacific Chiton Figure 66d Japan and Alaska to California. 6 to 12 inches in length, oblong and flattened. The large, white, butter- ISCHNOCHITONIDAE 319 fly-shaped valves are completely covered by the large, leathery, firm girdle which is reddish brown to yellowish brown. Minute red spicules make the girdle feel gritty. Common in the northern part of its range. Formerly called Cryptochiton stellert. N X FOOT LAPPET GILLS Ficure 67. Atlantic Coast chitons, showing from the underside the position and length of gills and the nature of the lappets. a, Ceratozona rugosa Sby., 1 to 2 inches; b, Cryptoconchus floridanus Dall, 1 inch; ec, Calloplax janeirensis Gray, %4 inch; d, Chaetopleura apiculata Say, ¥% inch; e, Tonicia schrammi Shuttleworth, 1 inch; f, Chiton tuberculata Linné, 3 inches. Family ISECHNOCHITONIDAE Genus Calloplax Thiele 1909 Calloplax janeirensis Gray Rio Janeiro Chiton Figure 67¢ Lower Florida Keys and the West Indies. Brazil. % to *4 inch in length, oblong, gray to greenish brown, or speckled with red. Very strongly sculptured. Lateral areas strongly elevated by 3 to 4 very coarse, large, beaded ribs; anterior valve with 12 to 18 such ribs. Central ridge (or jugal tract) with longitudinal rows of fine beads; apex elevated, smooth and rounded. Central area with about 12 very sharp, gran- ulose, longitudinal ribs. Interior white. Anterior valve with 10, middle valves with 1 and posterior valve with g slits. Girdle with very fine “sugary” scales and an occasional single hair. Gills start 4% the way back from the head and extend posteriorly to a large, fleshy lappet on the posterior margin of the girdle. An uncommon species. Genus Chaetopleura Shuttleworth 1853 Chaetopleura apiculata Say Common Eastern Chiton } Figures 67d; 68 Cape Cod, Massachusetts, to both sides of Florida. ¥, to % inch in length, oblong to oval. Valves slightly carinate. Central 320 American Seashells areas with 15 to 20 longitudinal rows of raised, neat beads. Lateral areas distinctly defined, raised and bear numerous, larger, more distantly spaced beads which may or may not be present on the more dorsal region. Interior white or grayish. Slits of anterior valve 11, central or middle valves 1, posterior valve 9g to 11. Girdle narrow, mottled cream and brown, microscopically granulose and with sparsely scattered, transparent, short hairs. 22 to 24 gill lamellae in each gill which start just be- hind the juncture of the head and foot and Be NE oe ar etntrs Hcy extend all the way back to the posterior Chiton, Chaetopleura apiculata ™argin of the mantle where there is located Say, %4 inch. a small, single-lobed lappet. Common from 1 to 15 fathoms. In the north, the exterior color is buff to ashen, rarely reddish. On the west coast of Florida, where they are commonly found attached to Pinna shells, the colors vary from light-gray, mauve, yellow to white, and are commonly with a darker or lighter streak down the center or rarely with longitudinal blue stripes. Genus Ischnochiton Gray 1847 Subgenus Stenoplax Carpenter 1878 Ischnochiton floridanus Pilsbry Florida Slender Chiton Miami to Dry Tortugas, Florida. 1 to 1% inches in length, about 3 times as long as wide, elevated, with the valves roundly arched, not carinate. Color whitish to whitish green with markings of olive, blackish olive or gray. Lateral areas raised and with wavy, longitudinal riblets which are commonly strongly beaded. Central areas with wavy, longitudinal ribs. Interior of valves mixed with white, blue and pink, rarely all pink or all white. End valves concentrically (or rarely axially) beaded. Intermediate valves with 1 slit, posterior valve with 9. Girdle marbled with bluish and gray, and densely covered with round, solid, finely striated scales. Moderately common. Ischnochiton purpurascens C. B. Adams (Purplish Slender Chiton) from the West Indies is very similar, but the end valves and lateral areas have smooth, instead of beaded, wavy, concentric riblets. Common. Ischnochiton papillosus C. B. Adams Mesh-pitted Chiton Tampa to the Lower Keys and the West Indies. =o. | | ISCHNOCHITONIDAE 321 ¥% to % inch in length, oval. Moderately sculptured and without very distinct lateral areas. It has microscopic, even, quincunx pittings on the upper surfaces of the valves. End valves with concentric rows of fine, low beads. Lateral areas with fine, wavy, longitudinal, incised lines. Posterior slope of posterior valve is concave and with 9 slits. Color whitish with heavy mottlings of olive-green; rarely with white spots. Girdle narrow, colored with alter- nating bars of white and greenish brown. Scales like microscopic split peas which are finely striated. A fairly common shallow-water species. Ischnochiton magdalenensis Hinds Magdalena Chiton Coos Bay, Oregon, to Lower California. 2 to 3 inches in length, elongate. Color a drab greenish, commonly whitish due to wear. Central areas with fine, irregular, longitudinal cuts and with diamond-shaped pits near the lateral areas. Lateral areas prominently raised and with ro to 12 coarse, radial ribs of gross, low beads. Front slope of anterior valve straight. Interior of valves bluish with the posterior end of each whitish. Girdle rather narrow and with alternating, faint bars of brown and yellowish brown. Scales round and so small that the girdle has the texture of fine sandpaper. Common. Ischnochiton conspicuus Pilsbry Conspicuous Chiton San Miguel Island, California, to the Gulf of California. 2 to 6 inches in length, very similar to magdalenensis, but the front slope of the anterior valve is very concave; the central areas are practically smooth and with flecks of green. Scales are elongate, hard, and so densely packed that the girdle feels velvety. Interior of valves pinkish and blue. Moderately common between tides. Ischnochiton acrior Pilsbry Acrior Chiton San Pedro, California, to Lower California. 2 to 6 inches in length, very similar to magdalenensis. Instead of dia- mond-shaped pittings on the sides of the central areas, there are wavy ribs. The front slope of the anterior valve is very concave, as in conspicuus. The scales are similar to those in magdalenensis, but much larger. Interior of valves pinkish with a blue spot at the anterior end of each valve. Moderately common. 322 American Seashells Ischnochiton regularis Carpenter Regular Chiton Southern California. 1 to 1% inches in length, oblong, appears smooth to the naked eye. Color an even slate-blue or uniform olive-blue. Valves slightly carinate. Central areas with very fine, longitudinal threads. Lateral areas slightly raised and with radial threads. Interior of valves gray-blue. Girdle with very tiny, closely packed, low, round scales. Moderately common between tides. Subgenus Lepidopleuroides Thiele 1928 Ischnochiton albus Linné White Northern Chiton Arctic Seas to Massachusetts. Europe. Arctic Seas to off San Diego, California. About % inch in length, oblong, moderately elevated. Upper surfaces smoothish except for irregular, concentric growth ridges and a microscopic, sandpapery effect. Color whitish, cream, light-orange or rarely marked with brown. Interior of valves white. Posterior valve with 12 to 13 weak slits. 17 to 19 gill lamellae on each side, beginning about halfway alongside the foot. Girdle sandpapery, with tiny, closely packed, gravelly scales. Com- mon from shore to several fathoms in cold water. Distinguished from ruber by the anterior slope of the anterior valve which is straight to slightly con- cave in albus, but convex in ruber. Ischnochiton ruber Linné Red Northern Chiton Arctic Seas to Connecticut. Europe. Alaska to Monterey, California. % to 1 inch in length, oblong, moderately elevated and with the valves rather rounded. Upper surfaces smooth except for growth wrinkles. Colored a light-tan over which is a heavy suffusion of orange-red marblings, or en- tirely suffused with red. Interior of valves bright pink. Posterior valve with 7 to 11 slits. Girdle reddish brown with weak maculations; covered with minute, elongate scales which do not overlap each other. 15 to 18 gill la- mellae, similar to those in albus. Common from 1 to 80 fathoms. Do not confuse with Tonicella marmorea Fabr. whose girdle is naked. Subgenus Lepidozona Pilsbry 1892 Ischnochiton mertensi Middendorft Merten’s Chiton Aleutians to Lower California. ISCHNOCHITONIDAE 323 1 to 1% inches in length, rather oval in shape. Color variable: com- monly yellowish with dark reddish brown streaks and maculations. Central areas with strong, longitudinal ribs and smaller, lower cross ridges which give a netted appearance. Jugal area V-shaped and with 5 to 6 smooth longi- tudinal ribs. Lateral areas raised, smoothish and with a few prominent warts. Anterior valves with 30 or more radial rows of warts which are largest near the girdle. Interior whitish, or rarely tinged with pink. Girdle with al- ternating yellowish and reddish bands; covered with tiny, low, smooth, split- pea scales. Very abundant just offshore, especially in the northern part of its range. Ischnochiton californiensis Berry Trellised Chiton Southern California to Lower California. 1 to 1% inches in length, oval to oblong, heavily sculptured. Color a dull-greenish with yellowish splotches and with a dark-brown area on the top of each valve. Central area with longitudinal and cross ribs which give a strong netted appearance. Lateral areas raised and with 4 rows of prominent beads. Posterior edge of valves serrated with about 20 small tooth-shaped beads. Anterior valve with 20 to 27 strongly granular ribs. Girdle closely packed with convex, tiny, split-pea scales. Moderately common and for- merly thought to be I. clathratus Reeve which, however, is only from the Panamic Province to the south. Ischnochiton cooperi Pilsbry Cooper’s Chiton Southern California. 1 to 1% inches in length, rather oval in shape. Color olive-green to olive-brown and clouded with light-blue. Central area with closely packed, sharp, longitudinal ribs which are finely striated. Jugal area with the same type of ribs and with its anterior end having about ro notches. Lateral areas raised and with 4 to 8 irregular rows of prominent, rounded warts. Interior of valves bluish. Girdle covered with tiny, flat, striated, split-pea scales. Uncommon. Ischnochiton palmulatus Pilsbry Big-end Chiton Southern California. % inch in length, oblong and with the posterior valve massive and greatly swollen. Color of valves yellowish brown to light grayish green with dark blackish green in the areas just above the girdle. Central areas carinate at the top, with 20 to 30 strong, rounded, longitudinal ribs. Lateral 324 American Seashells areas greatly raised and with 2 convex, strong ribs of coarse beads. Anterior valve with 9 convex, beaded ribs. Posterior valve very high, convex and with 7 to 8 pairs of strong ribs. Interior bluish white. Girdle yellowish with reddish bands; thin, narrow and with microscopic, striated scales. Uncom- mon, Family CHITONIDAE Subfamily CHITONINAE Genus Chiton Linné 1758 Outer edges of insertion plates with tiny, sharp teeth or pectinations; girdle with small, hard scales that look like overlapping split peas; girdle colored with alternating bars of grayish green and black; interior of valves blue-green. Key to the American Chiton Valves entirely smooth: Girdle scales glassy; sinus of valves narrow . . Jaevigatus (Pacific) Girdle scales dull; sinus of valves wide . . marmoratus (Atlantic) Valves with sculpturing: Central area with longitudinal ribs: Posterior valve with round pimples . . tuberculatus (Atlantic) Posterior valve with radiating ribs . . . virgulatus (Pacific) Central area smoothish and dull . . . . squamosus (Atlantic) Chiton tuberculatus Linné Common West Indian Chiton Plate 1d; figure 67f Florida to Texas and the West Indies. 2 to 3 inches in length. Color a dull grayish green or greenish brown. Some or all of the valves may have a smooth, dark-brown, arrow-shaped patch on the very top. Girdle with alternating zones of whitish, green and black. The scales are placed on the girdle, so that they appear slightly higher than broad, while in squamosus they appear to be broader than high. Lateral areas with 5 irregular, radiating cords. Central areas smooth at the top and with 8 to 9 long, strong, wavy, longitudinal ribs on the sides. End valves with irregular, wavy radial cords. Gills beginning at the juncture of the head and foot and with 46 to 48 lamellae. A very common species on wave-dashed, rocky shores. CHITONIDAE 325 Chiton squamosus Linné Squamose Chiton Southeast Florida and the West Indies. 2 to 3 inches in length. Color a dull, ashen-gray with wide, irregular, dull-brown, longitudinal stripes. Posterior edge of first 7 valves marked with 4 or 5 squares of blackish brown. Girdle with alternating pale stripes of grayish green and grayish white. Posterior valve with minutely pimpled ribs. Lateral areas of middle valves with 6 to 8 rows of small beads between which are microscopic pinholes. Central areas smoothish, with fine, transverse scratches. Common. Chiton viridis Spengler from the West Indies is very similar, but the margins of the central areas have 6 to 11 very short, wavy ribs, and the lateral areas have 3 or 4 strong ribs of rounded pustules, Uncommon. Chiton marmoratus Linné Marbled Chiton South Florida to Texas and the West Indies. 2 to 3 inches in length. Color variable: (1) entirely blackish brown; (2) olive with flecks, patches and lines of whitish merging together towards the middle; or (3) purplish brown or light-olive with zebra-like stripes on the sides. Entire surface of valves smooth except for a microscopic, silky texture. Lateral areas a little raised. Underside of posterior valve with 14 to 16 slits. A common West Indian littoral species. Chiton laevigatus Sowerby Smooth Panama Chiton Gulf of California to Panama. 2 to 3 inches in length, similar to marmoratus. Girdle scales broader than high and not very glossy. Valves smooth, with a silky sheen and colored a grayish green over which are radiating rays of dark-brown. Similar coloration in the other valves. Underside of posterior valve with 21 narrow slits. Sutural plates on underside of middle valves with a dark blotch at the base. Common. Chiton albolineatus Sowerby (western Mexico, uncommon) is also a smooth species, but differs in having only 16 to 17 slits in the posterior valve and has snow-white, radiating lines on the lateral areas and on the end valves, The girdle scales are light blue-green and edged with white. Chiton virgulatus Sowerby Virgulate Chiton Magdalena Bay, Lower California, to Panama. 326 American Seashells 2 to 3 inches in length, similar to tuberculatus. Girdle scales glassy. End valves with rather even, raised, radiating threads. Middle valves with the lateral areas bearing about 8 raised threads which split in two at the margin of the valve. Central area with about 60 to 70 even, longitudinal threads. Posterior valve with 19 to 20 prominent slits. Common. The closely re- sembling species, C. stokesi Broderip, from Mexico to West Colombia has only 15 to 16 slits in the posterior valve. Subfamily ACANTHOPLEURINAE Genus Acanthopleura Guilding 1829 Subgenus Maugeria Gray 1857 Acanthopleura granulata Gmelin Fuzzy Chiton South half of Florida and the West Indies. 2 to 3 inches in length, usually so worn and eroded as to eliminate the brown color and granulated sculpturing. Girdle thick, ashy white with an occasional black band, and matted with coarse, hair-like spines. Underside of valves colored a light-green, with the middle valves having a rather large, black splotch behind the sinus. Posterior valve with about 9 slits. Compare with Ceratozona rugosa whose gills do not extend to the very posterior end as they do in this species. Common. Genus Tonicia Gray 1847 Resembling Chiton in having pectinate or toothed sutural plates, but the girdle is naked and the upper surface of the valves have microscopic eyes. Tonicia schrammi Shuttleworth Schramm’s Chiton Figure 67e Southeast Florida and the West Indies. About an inch in length, colored a brownish red to buff and with darker mottlings and speckles. Upper surface of valves glossy; interiors white with a crimson stain in the center. Lateral areas separated from the smooth central area by a strong, rounded rib. The central area has a pep- pering of about 75 tiny, black eyes. Head valve smooth except for 8 to 10 broad rays of tiny, black eyes. Girdle naked, leathery and brownish to flesh- colored. Posterior valve with 14 slits. 36 lamellae in each of the 2 gills. They begin just behind the juncture of the head and the foot and extend back almost to the posterior end where there is a bilobed, small, fleshy lappet. A moderately common, intertidal species. Cie LE RALX Dentaliums and Other ‘Tusk-Shells Class SCAPHOPODA Family SIPHONODENTALIIDAE The tusk-like shell is generally swollen in the middle and is entirely smooth. The foot is worm-like and can be expanded at the end into a round disk. The median tooth of the radula is almost as long as wide. Genus Cadulus Philippi 1844 Shell small, white, without sculpture and swollen in the middle some- what like a cucumber. Aperture constricted and very oblique. The genus is divided into four subgenera as follows: Apex With./2 deep slits; 2. i... . Dischides Jeffreys 1867 Apex with 4 deep slits © ©. Polyschides Pilsbry and Sharp 1897 Apex with 2 or 4 shallow slits . . . Platyschides Henderson 1920 Apex without slits: Obese, convex on both sides . . . . .. .. .Cadulus s. str. Slender, almost flaton oneside. . . . . Gadila Gray 1847 Subgenus Polyschides Pilsbry and Sharp 1897 Cadulus carolinensis Bush Carolina Cadulus Figure 69a North Carolina to Florida and to Texas. 10 mm. in length. Slightly swollen. Apex with 4 shallow slits. In cross- section the shell is roundish. Commonly dredged from 3 to 100 fathoms. 52] 328 American Seashells Cadulus quadridentatus Dall Four-toothed Cadulus Figure 69b North Carolina to both sides of Florida and the West Indies. 5 to ro mm. in length, swollen behind the aperture. Apex with 4 well- defined slits. In cross-section the shell is roundish. Commonly dredged from 3 to so fathoms. Subgenus Gadila Gray 1847 Cadulus mayori Henderson Mayor’s Cadulus Southeast Florida. 3 to 4 mm. in length, swollen just anterior to the middle of the shell. Apical opening % the size of the aperture and usually has 1 or 2 callus rings within the opening. Fairly common from 16 to 100 fathoms. Family DENTALIDAE Shell with the greatest diameter at the aperture. Foot conical and with epipodial processes. Median tooth of the radula twice as wide as long. Genus Dentalium Linné 1758 The shell is an elongate, curved tube open at both ends, and somewhat resembles an elephant’s tusk. The diagnostic characters are the type of sculp- turing (ribs, riblets and circular threads or incised lines), the form of the apex, the degree of curvature, the size and thickness of shell and the position and form of the apical slit. The ten or so subgenera are nebulous in charac- ter and definition and one should consult the works of J. B. Henderson, H. A. Pilsbry and W, H. Dall. Subgenus Dentalium s. str. Dentalium laqueatum Verrill Panelled Tusk North Carolina to south Florida and the West Indies. 1 to 2% inches in length, thick-shelled and dull-white in color. Apex sharply curved; anterior 7% of shell slightly arched. 9 to 12 strong, elevated, primary longitudinal ribs with equally spaced, concave intercostal (space between ribs) spaces. Ribs fade out at the anterior third. There are fine reticulations over the entire shell. A supplemental tube is present in the young shells. Abundant in sandy mud from 4 to 200 fathoms. DENTALIIDAE 329 Dentalium texasianum Philippi Texas Tusk Figure 69c North Carolina and the Gulf States. %4 to 1% inches in length, thick-shelled, well-curved, hexagonal in cross- section and dull, grayish white in color. The broad spaces between the ribs are flat. Common from 3 to ro fathoms. The subspecies cestwm Henderson from Texas has numerous, cord-like riblets between the six main ribs. ne O| mit@ar \ | aera cal Figure 69. Tusk Shells. a, Cadulus carolinensis Bush, % inch (southeast United States), showing an enlargement of the apical end; b, apical end of Cadulus quadri- dentatus Dall, ¥ inch (southeast United States); c, Dentalium texasianum Philippi, 1 inch (southeast United States), showing cross-section at each end; d, cross-section of D. pilsbryi Rehder, 1 inch (west Florida); e, D. eboreum Conrad, 2 inches (southeast United States); f, D. pretiosum Sowerby, 2 inches (Pacific Coast). a Subgenus Dentale Da Costa 1778 Dentalium entale stimpsoni Henderson Sumpson’s Tusk Nova Scotia to Cape Cod, Massachusetts. 1 to 2 inches in length, round in cross-section and dull, ivory-white in color. Region of the apex always very eroded and chalky. Surface uneven and with some longitudinal wrinkles in better preserved specimens. A poor subspecies of the north European D. entale Linné. Common from 8 to 1200 fathoms. The subgenus Amtalis H. and A. Adams is the same as Dentale. Dentalium occidentale Stimpson Western Atlantic Tusk Newfoundland to off Cape Hatteras, North Carolina. 330 American Seashells 1 to 1% inches in length. Primary ribs 16 to 18, fairly distinct in the young stages; sculptureless in the senile stage. Round in cross-section. Chalky-white when eroded. Common from 20 to 1,000 fathoms. Dentalium antillarum Orbigny Antillean Tusk South half of Florida and the West Indies. About 1 inch in length, roundish in cross-section. Primary ribs 9, but increasing to 12 near the middle and finally with 24 near the aperture. Mi- croscopic, transverse lines between the ribs. Color opaque-white, rarely reflecting a greenish tint. Encircled with weak, zigzag bands or splotches of translucent gray. Dentalium pilsbryi Rehder Pilsbry’s Tusk Figure 69d West Florida and Brazil only. 34 to 1% inches in length, roundish in cross-section. Primary ribs 9, with a smaller, weaker, rounded, secondary rib appearing between each. All ribs fade out toward the anterior end. Intercostal spaces flat, crossed by coarse growth lines. No transverse, microscopic sculpture. Color opaque- white; without gray splotches. Formerly known as D. pseudohexagonum Henderson 1920, not Arnold 1903, Uncommon from 2 to 5 fathoms. Dentalium pretiosum Sowerby Indian Money Tusk Figure 69f Alaska to Lower California. About 2 inches in length, moderately curved and solid; opaque-white, ivory-like, commonly with faint dirty-buff rings of growth. Apex with a short notch on the convex side. A common offshore species which was used extensively by the northwest Indians for money. Subgenus Fissidentalium Fischer 1895 Dentalium floridense Henderson Florida Tusk Southeast Florida and the West Indies. 2 to 3 inches in length, roundish in cross-section. Shell hard and yel- lowish white. Apex hexagonal with concave spaces between. Ribs increase to 24 anteriorly and are rounded, equal-sized and crowded. There is a long, narrow apical slit on the convex side. Rare from 35 to 100 fathoms. DENTALIIDAE 331 Subgenus Graptacme Pilsbry and Sharp 1897 Dentalium eboreum Conrad Ivory Tusk Figure 69e North Carolina to both sides of Florida and the West Indies. 1 to 2% inches in length, glossy, tvory-white to pinkish. Apical slit deep, narrow and on the convex side. Apical end with about 20 very fine longitudinal scratches. Common in sandy, shallow areas. Dentalium semistriolatum Guiding Half-scratched Tusk South Florida and the West Indies. About 1 inch in length. Similar to eboreum, but curved more, with apical slits on the side, and its color translucent-white with milky patches. Some specimens may be reddish near the apical end. Common from 1 to go fathoms. Dentalium calamus Dall Reed Tusk North Carolina to east Florida and the Greater Antilles. %4 to 1 inch in length, almost straight and glassy-white. Most of the shell has minute, longitudinal scratches (about 16 per mm.). The apical end is sealed over by a bulbous cap which bears a small slit. Uncommon. Subgenus Episiphon Pilsbry and Sharp 1897 Shells very small, needle-like, wholly lacking longitudinal sculpture and, as in some other *subgenera, having a projecting, thin tube at the posterior end after the tip is broken or lost. Only one species in the Western Atlantic. Dentalium sowerbyi Guilding Sowerby’s Tusk North Carolina and Texas to Florida and the Lesser Antilles. 10 to 15 mm. in length. Needle-like, not fragile, curved, glossy-white. Crowded rings of growth microscopic on tip. Apex without slit and from it projects a very thin inner tube. Erroneously known previously as D. filum Sowerby. Commonly dredged from 17 to 180 fathoms, GEA WR IR xX Scallops, Oysters and Other Clams Class PELECYPODA The bivalves or clams are dwellers of fresh, marine or brackish waters. They lack a head and are without jaws or radular teeth; they are protected by a pair of shelly valves which are connected or hinged by a horny ligament and which are moved by the contraction of one to three muscles attached to the inner sides of the valves; feeding is usually done with the aid of their ciliated or hair-covered gills. Further details have been presented in the chapter on “The Life of the Clam.” The class is also known as Lamielli- branchia, Bivalvia or Acephala. The class may be divided into the following orders and suborders: Order PALAEOCONCHA Suborder SOLEMY ACEA (Awning Clams) Order PROTOBRANCHIA Suborder NUCULACEA (Nut Clams) Order FILIBRANCHIA Suborder TAXODONTA (Ark Shells) Suborder ANISOMY ARIA (Scallops, Oysters, Sea Mussels) Order EULAMELLIBRANCHIA Suborder SCHIZODONTA (River Mussels) Suborder HETERODONTA (Cockles, Lucines, Venus) Suborder ADAPEDONTA (Mya and Razor Clams, Teredos) Suborder ANOMALODESMACEA (Pandora Clams) Order SEPTIBRANCHIA Suborder POROMYACEA (Dipper Clams, Meat Eaters) 332 SOLEMY ACIDAE 333 Order PALAEOCONCHA Family SOLEMY ACIDAE Genus Solemya Lamarck 1818 The Awning Clams are very primitive in their characters and they have no near relatives. Their shells are fragile, with a weak, toothless hinge, gaping at both ends, and covered by a polished, horny, brown periostracum which extends well beyond the margins of the valves. Subgenus Petrasma Dall 1908 Solemya velum Say Common Atlantic Awning Clam Plate 27a Nova Scotia to Florida. % to 1 inch in length, very fragile, and with a delicate, shiny, brown periostracum covering the entire shell and extending beyond the edges. Light radial bands of yellowish brown are present in some specimens. Chondro- phore supported by 2 curved arms. Commonly dredged in shallow water in mud bottom. Compare Florida specimens with occidentalis. Solemya borealis Totten Boreal Awning Clam Nova Scotia to Connecticut. 2 to 3 inches in length, very similar to veluwm, but more compressed, heavier, and colored grayish blue or lead on the inside of the valves (instead of purplish white). The striking difference is in the siphonal opening of the animal. In velwm, there are 2 small, median, low tubercles above the opening and 5 or 6 pairs of short tentacles at the lower end of the opening. In bo- realis, there are 3 pairs (one of which is large and long) of tentacles above the opening and about 15 smaller ones bordering the lower half. S. borealis is moderately common offshore, Solemya occidentalis Deshayes West Indian Awning Clam West coast of Florida and the West Indies. ¥% inch in length, similar to S. velum, but much smaller, and has only one slender ridge or rib bordering the chondrophore. Uncommon just off- shore. Described first by Deshayes in 1857, later by Fischer in 1858. Solemya valvulus Carpenter Pacific Awning Clam San Pedro, California, to the Gulf of California. 334 American Seashells % inch in length, thin, translucent. Periostracum shiny, light-brown, with slender, radial lines of darker brown which are finely striate posteriorly. Ligament bounded by a single, arched prop or rib. Uncommonly dredged offshore. Order PROOTOBRANCHIA Suborder NUCULACEA Key to Families a. Chondrophore below hinge present: b. External ligament absent; shell ovate . . . . . Nuculidae. bb. External ligament present; shell elongate . . . . Nuculanidae. aa. Chondrophore absent; shell ovate . ©. . . . . . = Madlletiidae. Family NUCULIDAE Genus Nucula Lamarck 1799 Shell ovate, usually less than 4 inch in size; interior pearly; ventral mar- ins usually with fine denticulations. g yi Figure 70. Atlantic Coast Nut Clams. a and b, Nucula proxima Say, % inch; c, N. tenuis Montagu, 4 inch (both coasts); d, N. delphinodonta Mighels, 45 inch; e, N. atacellana Schenck, % inch. Subgenus Nucula s. str. Nucula proxima Say Atlantic Nut Clam Figure 70a, b Nova Scotia to Florida and Texas. % inch in length, obliquely ovate, smooth. Color greenish gray with microscopic, embedded, axial, gray lines and prominent, irregular, brownish, concentric rings. Outer shell overcast with oily iridescence. Anterior end often with microscopic, axial lines. Ventral edge minutely crenulate. Com- mon just offshore in mud. NUCULIDAE 335 Nucula atacellana Schenck Cancellate Nut Clam Figure 7o0e Massachusetts to Maryland. %s inch in length and oval in outline; the cancellate sculpturing is due to the crossing of numerous radial and concentric threads. Interior scarcely pearly and with a thick, transparent glaze. Color yellowish brown to light- tan. Commonly dredged offshore down to 500 fathoms. Formerly known as N. reticulata Jeffreys and cancellata Jeffreys. Nucula crenulata A. Adams Atlantic Crenulate Nut Clam South Carolina to Key West, Florida. % inch in length, ovate, internal margin finely crenulate. With numer- ous concentric, fine ribs which have numerous microscopic crenulations be- tween them. Interior scarcely pearly; overlaid by a thick, transparent layer of shell matter, through which radial fractures or lines are discernible; color yellowish. Dredged in shallow water. Similar in outline to N. tenuis (see fig. 70c). Nucula exigua Sowerby Pacific Crenulate Nut Clam Southern California to Ecuador. %46 inch in length (5 mm.), shaped like tenuis and the preceding species. Concentric rings strong with radial crenulations between. Strongly project- ing lunular area just under the beaks. Color yellowish. Dredged in shallow water. Very similar to N. crenulata from the Western Atlantic. Nucula delphinodonta Mighels Delphinula Nut Clam Figure 70d Nova Scotia to Maryland. %« inch (3 mm.) in length, ovate, fat and smooth except for coarse concentric growth lines. Anterior end slightly pushed in under beaks and bordered by slight carination. Ventral edge smooth. Color olive-brown. g teeth posterior to and 4 teeth anterior to chondrophore. Nucula tenuis Montagu Smooth Nut Clam Figure 70c Labrador to Maryland. Alaska to Lower California. Usually %6 inch in length (up to % inch in Alaska), ovate, smooth except for irregular growth lines. Color a shiny olive-green, sometimes with darker lines of growth. No radial lines. Ventral edge smooth. 336 American Seashells Genus Acila H. and A. Adams 1858 Similar to Nucula but characterized by the presence of divaricate sculp- ture on the outside of the shell. One common species in North American waters. Subgenus Truncacila Schenck 1931 Shell without the shallow sinus as seen in true Acila, and the posterior end of the shell nearly at right angles. Acila castrensis Hinds Divaricate Nut Clam Figure 72¢ Bering Sea to Lower California. ¥% inch in length, abruptly truncate at the anterior end. Divaricate, radiating ribs plainly visible. Commonly dredged from 4 to 100 fathoms in sandy mud. Family NUCULANIDAE Genus Nuculana Link 1807 (Leda Schumacher 1817) Nuculana pernula Miller Miiller’s Nut Clam Arctic Ocean to Cape Cod. Northern Alaska. % to 1 inch in length, elongate and truncate posteriorly, moderately fat, slightly gaping at the rounded anterior end. Numerous raised, concen- tric growth lines. Periostracum light-brown to dark green-brown, semi- glossy. Shell dull-white, interior shiny-white. Interior of rostrum (posterior end of shell) reinforced by a strong radial roundish low rib. Lunule long, prominent, with sharp edge. Commonly dredged offshore in cold water. N. conceptionis Dall is much more elongate, smoother and glistening brown. Nuculana minuta Fabricius (Arctic to off San Diego; and to Nova Scotia) is % inch in length, 7% as high, rather plump, and with a short ros- trum whose smoothish lunule is bounded by a rather coarse rib. Concentric, raised threads are numerous and crowded. Beaks are one third to almost one half the way back from the rounded anterior end. Uncommon offshore. Nuculana tenuisulcata Couthouy Thin Nut Clam Figure 71a Arctic Seas to Cape Cod. Up to % inch in length, elongate, moderately compressed; rostrum mod- erately long with a sharp, high keel down the dorsal center (margin of the ————— NUCULANIDAE 387 valves). Concentric ribs fairly even, well-developed, numerous. Periostra- cum light- to dark-brown. Commonly found in mud just below low-tide mark. Figure 71. Nut and Yoldia Clams. a, Nuculana tenuisulcata Couthouy, 94 inch (Atlantic); b, Yoldia limatula Say, 2 inches (Arctic waters, both coasts); e, Yoldia monterey ensis Dall, 1 inch (California). Nuculana carpenteri Dall Carpenter’s Nut Clam North Carolina to West Indies. About % inch in length, compressed, thin, translucent yellow-brown, with a long, slightly upturning rostrum. Anterior end round. Umbones very small, close together. Almost smooth except for minute, concentric growth lines and microscopic axial scratches which are absent in dead, white valves. Commonly dredged offshore from 10 to 100 or more fathoms. Nuculana fossa Baird Fossa Nut Clam Alaska to Puget Sound, Washington. %4 to 1 inch in length, elongate, moderately fat and smoothish except for small, pronounced, concentric ribs at the anterior end and on the beaks. Dorsal area of rostrum smoothish, depressed and bounded by 2 weak radial ribs. Periostracum dark- to light-brown. Dredged offshore in shallow water. Some workers consider the following forms or variations as subspecies: sculpta Dall, vaginata Dall and curtulosa Dall. Subgenus Ledella Verrill and Bush 1897 Nuculana messanensis Seguenza Messanean Nut Clam Cape Cod to the West Indies. 338 American Seashells Ys to % inch in length, moderately elongate, with a very short, slightly pinched rostrum. Almost smooth except for a few very small concentric growth ridges near the base of the shell. When alive, glistening light-brown with a slight oily iridescence. When dead, grayish white with concentric chalk streaks. Commonly dredged in moderately deep water. One of our smallest species. Subgenus Saccella Woodring 1925 Nuculana acuta Conrad Pointed Nut Clam Cape Cod to the West Indies. % to % inch in length, moderately elongate, with a sharp-pointed poste- rior rostrum. Concentric ribs evenly sized and evenly spaced and extending over the rib which borders the dorsal surface of the rostrum. Shell usually dredged dead in a white condition. Periostracum thin, very light yellowish. Common offshore. Nuculana concentrica Sa Concentric Nut Clam Ni Northwest Florida to Texas. % to % inch in length, strong, rather obese and moderately rostrate. Yellow-white, semi-glossy and with very fine, concentric grooves which are evident in adults on the ventral half of the valves. Beaks and the area just below smooth. Radial ridge on rostrum smoothish, not crossed by strong threads. Differing from acuta in being more obese, in having a smooth beak area, smooth rostral ridge and in having much finer, more numerous, con- centric threads or cut lines. Moderately common in 1 to 3 fathoms. Figure 72. Pacific Coast Nut Clams. a and b, Nuculana taphria Dall, % inch (California); c, Acila castrensis Hinds, % inch (Pacific Coast). Nuculana taphria Dall Taphria Nut Clam Figure 72a, b Bodego Bay, California, to Lower California. NUCULANIDAE 339 About % to % inch in length, shiny green-brown, with prominent con- centric sculpture and characterized by the nearly central umbones. Rostrum bluntly pointed, slightly upturned at the end. Concentric ribs disappear just anterior to the carinate border of the dorsal area which is strongly wrinkled. Adults over % inch become quite fat. Commonly dredged off southern Cali- fornia in shallow water. Sorensen reports that this species is found com- monly in fish stomachs off Monterey. Nuculana penderi Dall and Bartsch Pender’s Nut Clam Forrester Island, Alaska, to Santa Barbara, California. 4% to %g inch in length, moderately elongate, very fat; rostrum short and pointed; concentric ribs prominent and evenly developed. Dorsal area of rostrum oval, finely ribbed and bounded by a sharp, smooth, large mb. Periostracum light-brown. Moderately common offshore. Nuculana hindsi Hanley Hinds’ Nut Clam Nazan Bay, Alaska, to Costa Rica. % inch in length, moderately elongate (example: 7.8 mm. long; 4.4 mm. high; both valves 3.0 mm. wide); posterior end rostrate, slightly turned up at the end. Dorsal area of rostrum smoothish except for faint axial threads bounded by smooth carinate rib. Sculpture of evenly sized, closely spaced, distinct, concentric ribs which become obsolete just before the rostral rib. Exterior light yellowish brown. Interior white with faint pearly sheen. N. acuta Conrad, a name often given to this Pacific Coast species, has its rostral rib crossed by concentric ribs. N. penderi Dall and Bartsch is twice as fat, with a very ovate lunule and is more rounded at the ventral margin. Hanley in 1860 first reported this species from “Gulf of Nicoya, Costa Rica.” This is probably “N. redondoensis” “Burch” Woodring 1951. It is dredged com- monly off the West Coast from 15 to 600 fathoms. Subgenus Thestyleda Iredale 1929 Nuculana hamata Carpenter Hamate Nut Clam Figure 26d Puget Sound to Panama City, California. Under % inch in length, moderately compressed, exterior with strong concentric ribs; characterized by the squarely truncated posterior end of the long rostrum. Fairly commonly dredged off Californian shores from 20 to 200 fathoms. 340 American Seashells Genus VYoldia Moller 1842 Somewhat similar to Nuculana, but the valves are much thinner and fragile, rarely with a long rostrum, usually gaping at both ends, much smoother and glistening. Subgenus Yoldia s. str. Yoldia limatula Say File Yoldia Figure 71b Maine to Cape May, New Jersey. Northern Alaska. 1 to 2% inches in length, elongate, narrowing at the posterior end. Um- bones very small, halfway between the ends of the shell. Exterior glistening greenish tan to light chestnut-brown, with only faint concentric growth lines. Interior glossy white. A rather common species just below low-water mark. Distinguished from Y. sapotilla by its more elongate shape. It is pres- ent in northern Alaska, but it is replaced to the south by the following sub- species. Yoldia limatula gardneri Oldroyd Gardner’s Yoldia Southern Alaska to off San Diego, California. Very similar to the true /iatula, but always having the anterior ventral margin with a small concave depression. In general shape it falls within the variations of the Atlantic specimens. Moderately common. Yoldia sapotilla Gould Short Yoldia Plate 27b Arctic Seas to North Carolina. % to 1% inches in length, oblong, smooth, with a moderately extended posterior end. Periostracum yellowish to greenish brown. Differing from limatula in being shorter and less extended and more truncate at the poste- rior end. Commonly dredged off New England in shallow water; often found in fish stomachs. This species can be confused with the uncommon Y. myalis Couthouy (pl. 27d) which is found from Labrador to Cape Cod and Alaska and which, however, is shorter and more pointed at the posterior end. Subgenus Megayoldia Verrill and Bush 1897 Yoldia thraciaeformis Storer Broad Yoldia Plate 27e Arctic Seas to Cape Hatteras, North Carolina. Alaska to Puget Sound. ARCIDAE 341 1% to 2 inches in length, oblong. Characterized by its squarish, up- turned posterior end; coarse, dull, flaky periostracum, large circular chon- drophore; and the coarse, oblique mb running from beak to posterior ventral margin. Moderately common from shallow to deep water. Found in fish stomachs. Family MALLETIIDAE Shell not pearly inside, oval, compressed, gaping at both ends; ligament external, elongated, resting on nymphs; numerous teeth; no resilium. A linear depression extends from the umbonal cavity to the anterior muscle scar. Worldwide, usually deep water. Includes several genera and subgenera in- cluding Timdaria Bellardi 1875, Nedonella Dall 1881, Malletia Desmoulins 1832 and Protonucula Cotton 1930. Genus Tindaria Bellardi 1875 Shell small, resembling a tiny Venus clam; fat; beaks facing slightly for- ward; ligament minute, external; hinge smooth, continuous just below beaks. Generally deep water and rare. Tindaria brunnea Dall Brown Tindaria Bering Sea, Alaska, to Tillamook, Oregon. % inch in length, fat, moderately pointed at posterior end. Very fine concentric scratches. Exterior dark olive-brown. Interior glossy cream. Has been dredged abundantly in a few places in deep water. There are 8 other rare species on the West Coast of America. Order FILIBRANCHIA Suborder TAXODONTA Superfamily ARCACEA Key to Families a. Shell elliptical, hinge straight . - 2] | Aredae aa. Shell circular or lopsidedly circular, hinge carved: b. Ligament partly sunk intoshell . . . . . . . Limopsidae bb. Ligament external 5 Die ees Ree ait ne Glycvmmeriade Family ARCIDAE The ark shells have undergone intensive study in the last few years, and the nomenclature is still not settled. It is obvious, though, that not all of the 342 American Seashells arks can be placed under the single genus Arca. The geological history and morphological studies force us to recognize three subfamilies. Many of the subgenera listed here are considered by some authorities as full genera. | have refrained from defining their limits. Subfamily ARCINAE Genus Arca Linné 1758 Characterized by the long, narrow hinge line with numerous small teeth, by the large byssal notch on the ventral side, and the wide ligamental area between the beaks. Arca zebra Swainson Turkey Wing Plate 27n North Carolina to Lesser Antilles. Bermuda. 2 to 3 inches in length, about twice as long as deep. Color tan with flecks and zebra-stripe markings of reddish brown. Periostracum brown, matted. Ribs of irregular sizes. No concentric riblets. Do not confuse with A. umbonata. A common species which attaches itself to rocks with its byssus. Used extensively in the shellcraft industry. Formerly A. occiden- talis Philippi. Arca umbonata Lamarck Mossy Ark Plate 27] North Carolina to the West Indies. 1% to 2% inches in length. Similar to A. zebra, but differing in having beaded ribs and a very large byssal opening, usually having the posterior end much larger, and in lacking the zebra stripes. Periostracum sometimes quite heavy and foliated. Commonly attached to underside of rocks in shallow water. Genus Barbatia Gray 1847 Subgenus Barbatia s. str. Barbatia candida Helbling White Bearded Ark Plate 275 North Carolina to Brazil. 1% to 2% inches in length; fairly thin, not heavy. Irregular in shape. Byssal opening at base of shell. Numerous weak, slightly beaded ribs; those on the posterior dorsal area being very strongly beaded. Periostracum brown, longest at posterior end. Exterior and interior of shell white. Liga- ARCIDAE 343 ment moderately developed. This species was also named candida Gmelin, jamaicensis Gmelin and helblingi Brug. Common, attached under stones. Barbatia cancellaria Lamarck Red-brown Ark Plate 27q Southern Florida and the West Indies. 1 to 1% inches in length, similar to B. candida, but with low, cancel- late sculpture and colored a dark, purplish brown. This is a common species which is erroneously called B. barbata Linné (a Mediterranean species). Subgenus Acar Gray 1857 Barbatia domingensis Lamarck White Miniature Ark Plate 270 North Carolina to Florida and the Lesser Antilles. ¥, to % inch in length, somewhat box-shaped, whitish in color and with no appreciable periostracum. Similar in shape and sculpture to Arcopsis adamsi, but instead of having a small, triangular ligament between the beaks, domingensis has a very narrow, long ligament posterior to the beaks. The posterior end is usually larger than the anterior end and characteristically dips slightly downward. Common at low tide under rocks. Erroneously called Arca reticulata Gmelin by Dall and others (see Lamy and Woodring). Barbatia bailyi Bartsch Baily’s Miniature Ark Santa Monica, California, to Gulf of California. A little over % inch in length, oblong to squarish, fat; cancellate sculp- ture in which the beads become foliate at the posterior end. Ligament small, narrow and placed well posterior to the fairly close beaks; about 15 teeth. Color white to brownish white. Very common in certain localities under stones at low tide. A. pernoides Carpenter was thought to be this shell but is apparently some other much larger species of unknown identity. Subgenus Fugleria Reinhart 1937 Barbatia tenera C. B. Adams Doc Bales’ Ark Plate 27k Southern half of Florida to Texas and the Caribbean. 1 to 1% inches in length, thin-shelled, rather fat and evenly trapezoidal in shape and with numerous rather evenly and finely beaded, thread-like ribs. Ligamental area fairly wide at the beak end, becoming narrow at the other. 344 American Seashells Small byssal gape present on the ventral margin. Moderately common. Arca balesi Pilsbry and McLean is this species. Genus Arcopsis von Koenen 1885 Ligament limited to a very small, triangular, or bar-like area between the umbones. Arcopsis adamsi E. A. Smith Adams’ Miniature Ark Figure 26b Cape Hatteras, North Carolina, to Brazil. ¥% to % inch in length, oblong in shape, moderately fat, flattened sides; white to cream in color. Periostracum very thin. Sculpture cancellate. Lig- ament limited to a very small, triangular, black patch between the umbones. The muscle scars are usually bordered by a calcareous ridge. Inner margin of valves smooth. Common under rocks. Subfamily ANADARINAE Genus Anadara Gray 1847 Subgenus Larkinia Reinhart 1935 Anadara multicostata Sowerby Many-ribbed Ark Newport Bay, California, to Panama. Shell large, 3 to 4 inches in length, very thick and squarish. 31 to 36 radial ribs. The left valve slightly overlaps the right valve. Found in sandy areas by dredging in depths over 12 feet. A. grandis Broderip and Sowerby in Mexican and Panamic waters is larger, heavier and has 25 to 27 ribs. Anadara notabilis Roding Eared Ark Plate 27p Northern Florida to the Caribbean and Brazil. Bermuda. 1% to 3% inches in length. 25 to 27 ribs per valve. Fine concentric threads cross the ribs and are prominent between the ribs. The ribs never split. Rare in Florida; common in the West Indies. Formerly called auriculata Lamarck which is from the Red Sea. A. deshayesi Hanley 1s a synonym of notabilis. Anadara lienosa floridana Conrad Cut-ribbed Ark Plate 27-0 North Carolina, Florida to Texas and the Greater Antilles. ARCIDAE 345 2% to 5 inches in length, elongate. Ribs 30 to 38 in number, square, faintly divided by a fine-cut line. Fine, raised, concentric lines seen between weakly beaded ribs. Left valve very slightly larger than right valve. Peri- ostracum light- to dark-brown. Not very common. Typical lienosa Say is fossil and very close in characters to floridana. This species has often been called A. secticostata Reeve which 1s not so elongate and whose origin is unknown. Anadara baughmani Hertlein Baughman’s Ark Off the Texas Coast. 1% inches in length, similar to A. lienosa floridana, but much fatter, with 28 to 30 weakly noduled ribs which are not split, and with a strongly posterior-sloping anterior ventral margin. Common offshore down to 50 fathoms. A. springeri Rehder and Abbott, published a month later, is this species. Anadara transversa Say Transverse Ark Plate 27s South of Cape Cod to Florida and Texas. % to 1% inches in length. Left valve overlaps right valve. Ligament fairly long, moderately narrow, rough or pustulose. Ribs on left valve usually beaded, rarely so on right valve; 30 to 35 ribs per valve. Periostracum gray- ish brown, usually wears off except along base of valves. Fairly common in mud below low water. The smallest of the Atlantic Anadaras. Distinguished from ovalis by its longer, wider, more distinct external ligament. A. sulcosa van Hyning 1946 1s this species. Subgenus Lunarca Gray 1847 The subgenera Argina Gray and Arginarca McLean 1951 are probably the same. Anadara ovalis Bruguicre Blood Ark Plate 27t Cape Cod to the West Indies and the Gulf States. 1% to 24% inches in length, not very thick, roundish to ovate; square, smooth ribs; ligament very narrow and depressed; beaks close together. Peri- ostracum black-brown, hairy. Ribs 26 to 35 in number. Dall considered the forms “pexata Say” and “americana Wood” too in- distinct for recognition. This species was known for a long time as cam- pechiensis Gmelin and is common. 346 American Seashells Subgenus Cunearca Dall 1898 Anadara brasiliana Lamarck Incongruous Ark Plate 27y North Carolina to West Florida to Texas and the West Indies. 1 to 2% inches in length; almost as high as long. Beaks facing each other at center of short, transversely striate ligamental area. Left valve over- laps right valve considerably. Ribs 26 to 28, square with strong bar-like beads. Periostracum thin, light-brown. A. incongrua Say is this species. A. chemnitzi Philippi from the Greater Antilles to Brazil is similar, but thick-shelled, less than 1 inch in length; the beaks are slightly forward of the center of the ligamental area. Subfamily NOETIINAE Genus Noetia Gray 1857 Beaks point posteriorly; valves the same size; ligament transversely stri- ate; posterior muscle scar raised to form a weak flange. Subgenus Eontia MacNeil 1938 The subgenus Eontia is an Atlantic group only. Noetia s. str. differs in having decidedly more regular sculpture, the ribs smoother and never di- vided; deeper and longer crenulations on the inner margin. There is only one Recent American true Noetia (reversa H. and A. Adams) which occurs from the Gulf of California to Peru. Noetia ponderosa Say Ponderous Ark Plate 27z; figure 28a Virginia to Key West, Louisiana and the Gulf of Mexico. 2 to 2% inches in length, almost as high as long. Ribs raised, square and split down the center by a fine incised line; 27 to 31 ribs per valve. Posterior muscle scar raised to form a weak flange. Periostracum thick, black, but wears off at the beaks. A common shallow-water sand-dweller. Fossil speci- mens are rarely found on Nantucket, Massachusetts, beaches, Family LIMOPSIDAE Genus Limopsis Sasso 1827 Rather small, obliquely oval, clams with tufted, velvety brown peri- ostracum. Hinge line curved, with a series of oblique teeth. The hinge resembles that of the Glycymeridae. Ligament external, small, central, tri- LIMOPSIDAE 347 angular. Mostly deep water. Four species on the Pacific Coast, about six on the Atlantic side. Figure 73. Limopsis diegensis Dall, % inch (California). a, interior of valve; b, exterior, showing the fur-like periostracum. Limopsis diegensis Dall San Diego Limopsis Figure 73 Santa Barbara Islands to Coronado Island, California. % to % inch in length, obliquely oval. Shell white; exterior glossy white with concentric striae, often studded by tiny pinpoint holes. Radial scratches present. Periostracum heavy, tufted with hairs, and often with a cancellate pattern. Uncommonly dredged below 20 fathoms. Limopsis cristata Jeffreys Cristate Limopsis Cape Cod to southeastern Florida. ¥% inch in length, similar to sulcata but much smaller, less tufted with periostracum, with the inner margin of the valves having a series of strong, pimple-like nobs or teeth, and the outside of the shell having its radial sculp- ture stronger than its faint concentric sculpture. Commonly dredged off Florida. Limopsis minuta Philippi (Newfoundland to both sides of Florida) is very Close to this species but has cancellate or beaded sculpture and attains a length of % inch. The shells of L. antillensis Dall (Florida to the Lesser Antilles) are % inch in size and unique in being brightly colored with pink, orange or yellow, Limopsis sulcata Verrill and Bush Sulcate Limopsis Plate 27f Cape Cod to Florida, the Gulf States and the West Indies. ¥ inch in length, strongly oblique, with prominent, rounded ribs which 348 American Seashells are finely cut on the upper edge by short radial grooves. Inner margin of valves smooth. Shell dull-white. Periostracum thick, tufted, extending be- yond the ventral edge of the shell. Commonly dredged in moderately shal- low water. Family GLYCYMERIDAE Genus Glycymeris DaCosta 1778 Shell heavy, usually orbicular, equivalve, porcellaneous, usually with a soft, velvety periostracum. Beaks slightly curved inward. Hinge heavy, with numerous, small, similar teeth. Ligament external, its area distinct and with diverging grooves. The largest muscle scar is at the anterior end. Often mis- spelled Gly cimeris or Glicymeris. Glycymeris pectinata Gmelin Comb Bittersweet Platee7i North Carolina to both sides of Florida and the West Indies. % to 1 inch in size; characterized by 20 to 4o raised, radial ribs which have no fine radial striae or scratches on them. Color grayish and commonly splotched with brown. A common shallow-water species. Glycymeris undata Linné Atlantic Bittersweet Plate 27g North Carolina to east Florida and the West Indies. 2 inches in length, heavy, smoothish, except for microscopic radial scratches and somewhat larger concentric scratches, giving a silky appear- ance. There are numerous very weak and hardly discernible radial ribs sepa- rated by lines of white. Beaks at about the middle of the ligamental area. Color cream to white with bold splotches of nut-brown. Interior all white or well-stained with brown. This is G. lineata Reeve. In the region of the Carolinas, an inch-long species (spectralis Nicol 1952) is found which is more oval, its beaks face slightly toward the rear and the color is almost a uniform light-brown. Both common. Glycymeris decussata Linné Decussate Bittersweet Plate 27h Southeast Florida and the West Indies. 2 inches in size, very similar to wndata, but differs in the posteriorly pointing beaks, and in having nearly all of the ligamental area in front of the beaks. The radial scratches are stronger. This is G. pennacea Lamarck. Moderately common. MYTILIDAE 349 Glycymeris americana DeFrance Giant American Bittersweet North Carolina to north Florida to Texas. Up to 5 inches in length, rather compressed, always much flatter than undata. Yhe dorsal or hinge side of large specimens is quite long. Beaks point toward each other and are located at the midpoint of the hinge. Color drab-gray or tan, rarely with weak mottlings. Rare. Glycymeris subobsoleta Carpenter West Coast Bittersweet Plate 31e Aleutian Islands to Lower California. 1 inch in size, subtrigonal, texture chalky. Periostracum velvety, but usually worn away. Ligament area short. Radial ribs flat, with narrow inter- spaces; usually white, but may be with light- to medium-brown markings. A rather common shallow- to rather deep-water species. MYTILUS VOLSELLA Figure 74. Hinges of some genera of mussels. Suborder ANISOMY ARIA Superfamily MYTILACEA Family MYTILIDAE Genus Crenella Brown 1827 Shells small, oval to oblong-oval, thin, brownish periostracum and with fine decussate radial ribs. Ligament weak, internal. Margins crenulated. In- 350 American Seashells terior of shell glossy-white with a faint trace of iridescence. Mantle open in front, and folded at the posterior end into a sessile excurrent siphon. Foot worm-shaped with a disk-shaped end. Hinge finely dentate. Crenella faba O. F. Miller Faba Crenella Figure 75a Arctic Seas to Nova Scotia. % to % inch in length, oval-oblong, with numerous radial ribs. Color reddish brown. Thin periostracum varnish-like. Byssus golden-brown. Com- mon offshore. Figure 75. Crenella Clams. a, Crenella faba Miller, 4 inch (Arctic waters); b and ec, Crenella glandula Totten, ¥% inch (New England); d, Musculus lateralis Say, % inch (Atlantic Coast) Crenella glandula Totten Glandular Crenella Plate 28); figure 75b, c Labrador to North Carolina. % to % inch in length, squarish, with the beaks near one corner. Radial ribs are fine, numerous, slightly beaded and often crossed by much finer, con- centric threads. Color olive-brown. A very common offshore, cold-water species. The smaller decussata has its beaks at the center of its more sym- metrical shell. Crenella decussata Montagu Decussate Crenella Bering Sea to San Pedro, California. Greenland to North Carolina. Less than % inch in size, oval, with numerous fine, decussated radial ribs. Color tan to yellowish gray. Dredged from 3 to 150 fathoms. A food of many marine fishes. Compare with glandula. Crenella divaricata Orbigny (North Carolina to southeast Florida and the West Indies) is even smaller than decussata, is pure white, and very in- flated. MYTILIDAE 351 Crenella columbiana Dall British Columbia Crenella Figure 26g, h Aleutian Islands to San Diego. A little over % inch in length, oval-oblong, inflated, with numerous very fine, decussate radial ribs. Color greenish yellow-brown. 10 to 100 fathoms. Genus Modiolus Lamarck 1799 This group of mussels have shells of various forms in which the hinge is without teeth. The anterior end of the shell extends in front of the beaks, while in Mytilus 3 to 5 tiny teeth are present on the hinge and the beaks are at the very anterior end of the shell. Volsella Scopoli has been rejected. Modiolus modiolus Linné Northern Horse Mussel Figure 26] Arctic Seas to northeast Florida. Arctic Seas to San Pedro, California. 2 to 6 inches in length, heavy, with a coarse, rather thick, black-brown periostracum which in dried specimens flakes off to reveal a mauve-white, chalky shell. One of the largest and commonest mussels found in cooler waters below low-water mark. Do not confuse with M. americanus. Modiolus americanus Leach Tulip Mussel Plate 351] North Carolina to the West Indies. 1 to 4 inches in length, smooth, except for the periostracum, which is commonly hairy and sometimes resembles a beard. Color light-brown flushed with deep rose and sometimes with several radial streaks of light-purple. An- terior ventral area with a deep chestnut splotch. Interior dull white, some- times stained with bluish, rose or brownish. Recently killed specimens are commonly washed ashore in large num- bers. A very common species. Formerly known as Volsella or Modiolus tulipa Linné or Lamarck. The subspecies found in Charleston Bay, North Carolina, and Tampa, Florida, is more compressed and a soft brown in color. Modiolus demissus Dillwyn Atlantic Ribbed Mussel Plate 28h Gulf of St. Lawrence to South Carolina. Introduced to California. 2 to 4 inches in length, black-brown in color, often shiny, and with strong, rough, radial, bifurcating ribs. Interior bluish white with the poste- rior end flushed with purple or purplish red. This is the only ribbed Modi- olus in our waters, but do not confuse it with Brachidontes recurvus which 352 American Seashells has a strongly curved beak, tiny teeth at the umbo, and is a solid rosy-brown on the inside. Mytilus plicatulus Lamarck is this species. The subspecies demzissus granosissimus Sowerby (both sides of Florida to Texas and Yucatan) is very similar but with almost twice as many ribs which are finely and neatly beaded. Common. Modiolus fornicatus Carpenter California Horse Mussel Plate 29-0 Monterey to San Pedro, California. About 1 inch in length, smoothish, inflated, light-brown periostracum which wears white at the beak end. Beaks curved strongly forward. Inte- rior dull white. Found in moderately deep water, and rarely cast ashore. Associated with Haliotis rufescens. Modiolus capax Conrad Capax Horse Mussel Santa Cruz, California, to Peru. 2 to 6 inches in size. Periostracum thick, often with coarse hairs, chestnut-brown in color. Worn shell brick-red with bluish mottlings. In- terior half white, half (ventral) brownish purple. Resembles figure of Modiolus americanus (Pl. 351). Genus Brachidontes Swainson 1840 Subgenus Brachidontes s. str. Brachidontes citrinus Roding Yellow Mussel Plate 351 Southern Florida and West Indies. 1/4 inches in length, elongate, with numerous wavy, fine axial ribs, col- ored a light brownish yellow outside, and inside mottled a metallic purplish and white. Anterior end has four very tiny white teeth. Bordering the liga- ment are about 30 very small, equal-sized teeth on the edge of the shell. Com- pare with B. exustus Linné which is wider. The genus is commonly mis- spelled Brachydontes. Subgenus Hormomya Morch 1853 Brachidontes exustus Linné Scorched Mussel Plate 35} North Carolina to the West Indies. %4 inch in length, rather elongate with numerous fine axial ribs; colored a yellowish brown to dark-brown outside, and inside mottled with a metallic MYTILIDAE Bo purplish and white. Anterior end has two very tiny purplish teeth. Beyond the ligament (posterior end) there are 5 to 6 very tiny, equal-sized teeth on the edge of the shell. Compare with B. citrinus, which is more elongate. Brachidontes stearnsi Pilsbry and Raymond Stearns’ Mussel Santa Barbara, California, to Oaxaca, Mexico. ¥% to 1 inch in length, obtusely carinate, with numerous coarse, beaded, radial ribs which bifurcate. Color brownish purple on the dorsal half, straw- yellow to brownish yellow on the flattened ventral half. Hinge on dorsal edge with about a dozen very tiny bar-like teeth. Usually found in colonies in crevices of stones. Two small clams, Lasaea cistula Keen and L. subviridis Dall, attach themselves to the byssus of this species. Do not confuse B. stearnsi with Septifer bifurcatus, with which it often lives. B. multiformis Carpenter and B. adamsianus Dunker are closely related species, if not mere forms, found in the Panamic province. Subgenus Ischadium Jukes-Brown 1905 Brachidontes recurvus Rafinesque Hooked Mussel Plate 35n Cape Cod to the West Indies. 1 to 2% inches in length, flattish, rather wide, with numerous wavy axial ribs. Color outside a dark grayish black, inside a purplish to rosy brown with a narrow blue-gray border. At the umbonal end there are 3 to 4 extremely small, elongate teeth on the edge of the shell. The anterior end of the shell is strongly hooked. This was known as M. hamatus Say and has sometimes been placed in the genus Mytilus. Genus Amygdalum Megerle von Mihlfeld 1811 Shell thin, very smooth, often with colored, cobwebby designs. These clams build nests for themselves with a copious supply of byssal threads. Amy gdalum papyria Conrad Paper Mussel Plate 281 Texas and Maryland to Florida. 1 to 1% inches in length, elongate, smooth, glistening, fragile, and colored a delicate two-tone of bluish green and soft yellowish brown. In- terior iridescent-white. The ligament is very weak and thin. A. sagittata Rehder, sometimes dredged off Florida and Mississippi, is very shiny, ivory- white, half of each valve with fine, gray, cobwebby streaks. The umbo is reinforced inside by a very small, smooth column or mb. 354 American Seashells Genus Septifer Recluz 1848 Septifer bifurcatus Reeve Bifurcate Mussel Crescent City, California, to Gulf of California. 1 to 2 inches in size, subtriangular in outline, inflated. With a couple of dozen strong, wavy radial ribs. Inner margin crenulated. Periostracum black, although often worn white between the ribs. Interior pearly-white, often stained bluish brown on one half of the inner side. The subspecies obsoletus Dall from San Diego is mostly black on the interior and is a quite elongate form. Genus Mytilus Linné 1758 Mytilus edulis Linné Blue Mussel Plate 35m Arctic Ocean to South Carolina. Alaska to California. 1 to 3 inches in length, no ribs but often with coarse growth lines. Ventral margin often curved. Color blue-black with eroded areas of chalky purplish. Periostracum varnish-like. Interior slightly pearly-white with deep purple-blue border. Occasionally, specimens have radial rays of brown- yellow. Very common in New England. Sometimes found in more south- erly waters attached to floating wood. Mytilus edulis diegensis Coe 1946 (Northern California to Lower Cali- fornia) is indistinguishable from specimens of edulis found in Alaska and New England, and probably only represents an ecological or physiological race (see W. R. Coe, 1946). Mytilus californianus Conrad Californian Mussel Plate z9p Aleutian Islands to Socorro Island, Mexico. 2 to 10 inches in length, thick, inflated; ventral margin nearly straight; with less than a dozen or so, fairly broad, weak radial ribs which are best seen on the middle part of the shell. Growth lines very coarse. An abun- dant species found between tides attached to rocks. Genus Musculus Roding 1798 Mussel-like shells with the sculpturing divided into three oblique areas, the center one being smooth or almost so, and the two end areas having radial ribs. The ligament is much longer than that in Crenella. ‘These are moderately deep-water clams. Mantle folded in front into a wide, incurrent MY TILIDAE 355) siphon and behind into a conical excurrent siphon. Foot strap-shaped. This genus was formerly known as Modiolaria Beck 1838. Hinge finely dentate. Musculus niger Gray Black Musculus Plate 28g Arctic Seas to North Carolina. Alaska to Puget Sound. About 2 to 3 inches in length. Similar to M. discors, but much more compressed and with strongly developed axial, decussated ribs on the pos- terior and anterior thirds. Center section with microscopic concentric wavy threads and pimples. Often pinkish on the inside. Common. Musculus laevigatus Gray Smooth Musculus Plate 28f Arctic Ocean to Puget Sound, and North Atlantic. 1 to 1% inches in length. Distinguished from discors by its larger size, and in having no pronounced radial riblet or depression separating the pos- terior third from the middle area. The periostracum is more often black in this species. The posterior area very often has numerous microscopic con- centric scratches which, to the naked eye, give this area a dull finish. Like discors, this species is much fatter than niger. Musculus lateralis Say Lateral Musculus Figure 75d North Carolina to Florida and the West Indies. %% inch in length, oblong, fragile, with a center area on the valve with concentric growth lines only. Remainder of shell with radial ribs. Color light-brown with a strong blush of blue-green. Interior slightly iridescent. Common offshore. Musculus discors Linné Discord Musculus Plate 28e Atlantic: Arctic Seas to Long Island Sound. Pacific: Arctic Seas to Puget Sound. 1 inch in length, oblong, fairly fragile. Anterior and posterior thirds of outer shell with very weak radial ribs; center section smooth except for irregular growth lines. Periostracum shiny and either dark black-brown or light-brown. Interior bluish white with slight iridescence. Commonly dredged. 356 American Seashells Genus Botula Morch 1853 Subgenus Adula H. and A. Adams 1857 Botula falcata Gould Falcate Date Mussel Plate 29k Coos Bay, Oregon, to Lower California. 2 to 4 inches in length, very elongate, slightly curved. Beaks rounded and about one-eighth the length from the anterior end; a strongly marked angle occurs from the beaks to the base of the posterior extremity; numerous vertical, wavy ribs over all the shell. Color a shiny chestnut-brown. Com- mon. Botula californiensis Philippi Californian Date Mussel Plate 29h 1 to 14 inches in length, elongate, curved and smooth, except for a velvety, hair-like covering over the posterior end. Shiny, chocolate-brown in color. Moderately common. Genus Lioberus Dall 1898 Lioberus castaneus Say Say’s Chestnut Mussel Both sides of Florida and the West Indies. %4 inch in length, oval-elongate, well-inflated and thin-shelled. Exterior chestnut- to dark-brown, the anterior half glossy, the posterior half dull and commonly with a fine grayish matting of periostracum. Interior bluish white and with an irregular surface. Hinge simple with a slight swelling or pad under the beaks. Moderately common in shallow water. Botula fusca Gmelin from North Carolina to southeast Florida (rare) and the West Indies (common) is similar, but distinguished by its longer, hooked or arcuate shape, by the thick, concentric ridges on the outside, by the more anteriorly placed beaks, and by the tiny, vertical threads on the hinge just posterior to the ligament. Attached in clusters to wood and rocks. Genus Lithophaga Roding 1798 Lithophaga nigra Orbigny Black Date Mussel Plate 28m Southeast Florida and the West Indies. 1 to 2 inches in length, elongate and cylindrical. Black-brown outside and an iridescent bluish white inside. Anterior lower third of each valve MY TFILIDAE 357 with strong, vertical, smooth ribs; remainder of shell smoothish with only irregular growth lines. Commonly found boring into soft coral blocks. Lithophaga antillarum Orbigny Giant Date Mussel Plate 28k Gulf of Mexico and the West Indies. 2 to 4 inches in length, elongate, cylindrical and colored a light yellow- ish brown on the outside and iridescent cream inside. Sides of valves marked with numerous, irregular, vertical riblets. Fairly common in soft rocks in moderately deep water. Subgenus Myoforceps P. Fischer 1886 Lithophaga aristata Dillwyn Scissor Date Mussel Plate 29} Southern Florida and the West Indies. La Jolla, California, to Peru. ¥, to 1 inch in length. Characterized by the pointed tips at the posterior end being crossed like fingers. Color yellowish brown, but generally covered by a smooth, gray, calcareous encrustation. Moderately common in soft rock. Subgenus Diberus Dall 1898 Lithophaga bisulcata Orbigny Mahogany Date Mussel Plate 28n North Carolina, the Gulf of Mexico, and the West Indies. 1 to 1% inches in length, elongate, cylindrical and coming to a point at the posterior end. A sharp, oblique, indented line divides each valve into two sections. Anterior half of valve smooth, mahogany-brown, but com- monly encrusted with porous, gray, calcium deposits. Posterior end more heavily encrusted with a gray, porous covering which projects beyond the edge of the shell. A fairly common rock-boring species. Lithophaga plumula kelseyi Hertlein and Strong Kelsey’s Date Mussel Plate 291 San Diego north to Mendocino County, California. 1 to 2 inches in length, similar to L. bisulcata, but the calcareous matter on the posterior end is strongly pitted and furrowed to look like a wet, ruffled feather. Typical plumula Hanley ranges from Lower California to Peru. Both fairly common in rocks. 358 American Seashells Superfamily PTERIACEA Family ISOGNOMONIDAE Genus Isognomon Solander 1786 Shell thin and greatly compressed; interior pearly; anterior margin with a narrow byssal gape near the dorsal margin. Hinge with numerous parallel grooves perpendicular to the dorsal margin of the valve. Perna Bruguieére and Pedalion Dillwyn are synonyms. Pedalion Solander 1770 1s invalid. [sognomon alatus Gmelin Flat Tree Oyster Plate 35b South half of Florida and the West Indies. 2 to 3 inches in length. Hinge has 8 to 12 oblong grooves or sockets into which are set small, brown resiliums. Exterior with rough or smoothish growth lines. External color drab purplish gray to dirty-gray. Interior moderately pearly with stains of purplish brown or mottlings of blackish purple. This very flat, oval bivalve is commonly found in compact clumps on mangrove tree roots. Distinguished from J. radiatus by its flat, more regularly fan shape and darker color. Isognomon radiatus Anton 1839 Lister’s Tree Oyster Plate 35a Southeast Florida and the West Indies. % to 2 inches in size, very irregular in shape, commonly elongate. Sometimes twisted and irregular. Hinge short, straight and with 4 to 8 very small, squarish sockets. Exterior rough with weak, flaky lamellations. Color a solid, translucent yellowish, but commonly with a few wavy, radial stripes of light purplish brown. Common on rocks at low tide. Formerly 1. Jisteri Hanley 1843. lsognomon bicolor C. B. Adams (Lower Florida Keys, Bermuda and Caribbean) is heavier, more oval, and commonly with strong lamellations on the outside. It is usually darkly and heavily splotched with purple inside and out. Common. According to Lamy, /. vulsella Lamarck is a different species which is limited to the Red Sea. The Western Tree Oyster, lsognomon chemnitzianus Orbigny, from the Coronado Islands to Chili, lives in crowded colonies under stones in shallow water. It resembles the above two species, is about 1 to 2 inches in size; its right valve flattish, left valve slightly swollen. It is the only Cali- fornian /sognomon. PINNIDAE 359 Family PTERIIDAE Genus Pteria Scopoli 1777 Fairly thin-shelled, moderately fat, and with the hinge ends considerably drawn out. Pearly inside. The right and left valves bear 1 or 2 small denticles which fit into shallow sockets in the opposite valve. Pteria colymbus Roding Atlantic Wing Oyster Plate 35d North Carolina to southeast Florida and the West Indies. 1% to 3 inches in length, obliquely oval with a long extension of the hinge line toward the posterior end. Left valve inflated. Right valve somewhat flatter and with a strong anterior notch for the byssus. Periostra- cum matted, brown and with cancellate fimbrications. Exterior color vari- able: brown, black or brownish purple with broken, radial lines of cream or white. Interior pearly with a wide, non-pearly margin of purplish black with irregular cream rays. Common from low water to several fathoms. The Western Wing Oyster, Pteria sterna Gould is very similar, 3 to 4 inches in length, and deep purplish brown with occasional paler rays. An- chored in mud; from San Diego to Panama. Common. Genus Pinctada Roding 1798 This is the famous genus of pearl oysters. The byssal gape is in the right valve below the small, triangular auricle. Margaritifera Schumacher is a synonym. Pinctada radiata Leach Atlantic Pearl Oyster Plate 35c South half of Florida and the West Indies. 1% to 3 inches in length, moderately inflated to flattish, thin-shelled and brittle. There is a small, thin, flat ligament at the center of the hinge. Exterior tan with mottlings or rays of purplish brown or black. Rarely tinted with dull-rose or greenish. In quiet waters, thin scaly and very deli- cate, periostracal spines may be developed. Interior a beautiful mother-of- pearl. Common in shallow water attached to rocks. Family PINNIDAE Genus Pinna Linné 1758 The Pen Shells are large, fragile, fan-shaped clams which live in sandy or mud-sand areas, usually in colonies. The apex or pointed end is deeply 360 American Seashells buried, and there is a mass of byssal threads attached to small stones or frag- ments of shells. The broad end of the shell projects above the surface of the sand an inch or so. In the genus Pinna, there is a weak groove running down the middle of each valve. In Atrina, this character is absent. Pinna carnea Gmelin Amber Pen Shell Plate 27w Southeast Florida and the West Indies. 4 to g inches in length, relatively narrow, thin-shelled and with a central, radial ridge in the middle of the valve which is more conspicuous at the pointed or hinge end. With or without 10 radial rows of moderately large, scale-like spines. Color usually a light orangish to translucent-amber. Rare in Florida but common in the Bahamas. This is the only Pinna in the western Atlantic. P. rudis Linné is apparently a Mediterranean and West African species which is heavier and darker red. The name P. haudignobilis Karsten is invalid, as are all this author’s names. Genus Atrina Gray 1842 Atrina rigida Solander Stiff Pen Shell Plate 27x North Carolina to south half of Florida and the Caribbean. 5 to g inches in length, relatively wide, moderately thick-shelled and with 15 to 25 radial rows of tube-like spines; rarely smoothish. Color dark to light brown. Commonly washed ashore. A small, commensal crab lives inside the mantle cavity. A number of unusual snails and chitons are found in or on dead or live Pinna shells. Atrina serrata Sowerby Saw-toothed Pen Shell Plate 27v North Carolina and south half of Florida. Similar in size and shape to rigida, but covered with many more, much smaller, sharp spines. It is usually thinner-shelled and lighter in color. Com- monly washed ashore with rigida. Superfamily PECTINACEA Family PLICATULIDAE Genus Plicatula Lamarck 1801 Shell trigonal or spathate, thick-shelled and attached by either valve to rocks or other shells. Sculpture of broad, radial ribs. Hinge with a nar- PECTINIDAE 361 row, elongate chondrophore which is flanked on each side by a fluted tooth and a socket. Plicatula gibbosa Lamarck Kitten’s Paw Plate 35e North Carolina to Florida, the Gulf States and West Indies. About 1 inch in length, somewhat cat’s-paw-shaped. Shell strong, heavy, with 5 to 7 high ribs which give the valves a wavy, interlocking margin. Hinge in upper valve with 2 strong, equally sized teeth; lower attached valve with 2 sockets in the hinge with 2 smaller teeth set rather close together. Color dirty-white to gray with red-brown or purplish lines on the ribs. A common intertidal to offshore species. Family PECTINIDAE Because of the great number of fossil and living species of scallops and the almost limitless modifications exhibited by them, there have been no less than 50 genera and subgenera proposed in this family by various authors. _ Doubtlessly, many more will be invented. Most, if not all, of these genera are closely integrated by connecting species. Workers have a choice of using the single genus, Pecten, or employing a genus for nearly every species. We are arbitrarily employing only six genera—Pecten, Aequipecten, Chla- mys, Placopecten, Lyropecten and Hinnites—and we cannot justify these on biological grounds. It may be noted that we have moved the glassy, thin- shelled Propeamussium from the Pectinidae into a family of its own on anatomical grounds. This new family refers to what was once called “Amus- sidae.” True Amusium, however, is merely a subgenus of Pecten connected to it by a series of species in the Euvola group. Genus Pecten Miller 1776 Subgenus Pecten s. str. Pecten diegensis Dall San Diego Scallop Plate 33e Cordell Bank, California, to Lower California. 2 to 3 inches in size. Right valve convex with 22 or 23 flat-topped ribs which are generally longitudinally ridged on top. Left valve much flatter, with 21 to 22 narrow, rounded ribs. Dredged from 10 to 75 fathoms. Subgenus Patinopecten Dall 1898 Pecten caurinus Gould Giant Pacific Scallop Plate 29b Wrangell, Alaska, to Humboldt Bay, California. 362 American Seashells 6 to 8 inches in size, roughly circular; upper valve almost flat, reddish gray and with about 17 low, rounded ribs; lower valve deeper, whitish and with a few more, stronger, rather flat-topped ribs. This is the common, edible deep-sea scallop of Alaska. Subgenus Amusium Roding 1798 Pecten papyraceus Gabb Paper Scallop The Gulf of Mexico and the West Indies. About 2 inches in size, oily smooth, glossy, exterior without ribs, but internally with about 22 very fine ribs which are commonly arranged in pairs. Both valves moderately convex to flattish. Upper valve light-mauve to reddish brown with darker flecks. Lower valve whitish at the center with yellow to cream margins or all white. Hinge line strongly arched. Rather rare in collections, but commonly brought up from several fathoms by shrimp fishermen. Pecten laurenti Gmelin (pl. 33f) from the Greater Antilles is larger, with a straight hinge line and with the lighter-colored valve more convex than the darker valve. Rare. Section Exuvola Dall 1897 Pecten ziczac Linné Zigzag Scallop Plate 33d North Carolina to Florida and the West Indies. 2 to 4 inches in size. Upper (left) valve flat; lower valve very deep and convex. There are 18 to 20 broad, very low, rather indistinct ribs on the deep valve which is generally colored a brownish red (rarely orange). The ribs fade out or are not present near the side margins of the valve. Flat valve with a bright mozaic of whites and browns. A fairly common species. Do not confuse with raveneli. Pecten raveneli Dall Ravenel’s Scallop Plate 33g North Carolina, the Gulf of Mexico, and the West Indies. 1 to 2 inches in size, similar to ziczac, but the deep valve has about 25 very distinct ribs which are commonly whitish in color. Between them are fairly wide, tan or pinkish grooves. In the flat valve, the 25 or so ribs are rounded in cross-section whereas in ziczac they are flat-topped and much closer together. A rather uncommon species. PECTINIDAE 363 Pecten tereinus Dall Tereinus Scallop Southern Florida and the Gulf of Mexico. 1 inch in size, quite fragile. Upper (left) valve flat, with about 20 small, narrow ribs; lower valve deep to moderately deep and with low, irregularly defined, roundish ribs. Color whitish tan, slightly translucent, with faint mottlings of pink near the beaks. Rarely, the flat valve may be flecked with brown, zigzag, fine lines. A rare species uncommonly dredged by private collectors in 10 to 4o fathoms. Genus Chlamys Roding 1798 Chlamys sentis Reeve Sentis Scallop Plate 34a North Carolina to southeast Florida and the West Indies. 1 to 1% inches in length, but not so wide (like a fan opened only 80 degrees). Valves rather flat. One hinge ear small, the other twice as large. With about 50 ribs of varying sizes, each with tiny, closely set scales. There are 2 to 4 smaller ribs between the slightly larger ones. Color commonly brilliant: purple, red, vermilion, orange-red, brownish, white or mottled (especially near the beaks). Common under rocks below low-tide mark. Do not confuse with ornata, mildredae or benedicti. Chlamys mildredae F. M. Bayer Mildred’s Scallop Plate 34¢ Southeast Florida and Bermuda. 1 to 1% inches in length, similar to sentis and ornata, but the ribs of the upper valve (one without the byssal notch) 30 in number and every third or fourth one larger. Sculpture of rather large, erect scales set about 1 mm. apart. Ribs of lower valve about 30, in groups of 2 or 3. Exterior color much like sentis; interior yellowish with purple stains near the margins. Rare under rocks at low tide. Chlamys ornata Lamarck Ornate Scallop Plate34b Southeast Florida to the West Indies. 1 to 1% inches in length, similar to sentis, but with about 18 high, major, slightly scaled ribs separated by 2 small, scaly cords on the upper valve. Ribs of lower valve are in 18 groups of 3alosely spaced riblets. Exterior ivory to yellowish cream with strong maculations of maroon or purplish. Interior usually white. Compare with mildredae. An uncommon and favorite collector’s item. 364 American Seashells Chlamys benedicti Verrill and Bush Benedict’s Scallop South half of Florida and the Gulf of Mexico. Rarely over % inch in length. Very similar to sentis, but with a greater range of colors and having 2 color variations not found in sentis (pure lemon- yellow or mottled with chalk-white zigzag stripes). With about 22 strong ribs alternating with weaker ribs, total about 45. Shorter ear has a sharp, go-degree corner and bears prominent spines, while in senzzs it 1s more rounded or considerably more than 90 degrees and is smoother. Hinge margin of longer ear has small projecting scales. Color pink, pinkish red, light purple or yellow, and commonly with pronounced whitish zigzag markings. A moderately common species usually misidentified as young setis or m7uscosa. Chlamys wnbricata Gmelin Little Knobby Scallop Plate 34f Southeast Florida and the West Indies. 1 to 1% inches in length, but not quite so wide. Lower valve (the one with the byssal notch) slightly convex. Upper valve almost flat and fairly thin. Ribs 8 to ro, uncommonly with smaller cords between. They have prominent, cup-shaped, delicate, distantly spaced scales. Color dirty-white or pinkish with small, squarish, red or purplish blotches. Interior yellowish, commonly with purplish stains. Moderately common. Chlamys hastata hastata Sowerby Pacific Spear Scallop Plate 34] Monterey to Newport Bay, California. 2 to 2% inches in size; without microscopic reticulations;, right valve (with byssal notch) with about 18 to 21 primary, strongly spined ribs which have 5 to 7 much smaller, weakly spined, secondary ribs in between left valve with ro to 11 distantly spaced, strongly scaled primary ribs, with 12 to 16 very weak, beaded secondary ribs in between. This is not so common as the subspecies hericia, and is much more colorful, commonly being bright orange, red or lemon. Chlamys hastata hericia Gould Pacific Pink Scallop Plate 34k Alaska to San Diego, California. 2 to 2%4 inches in size; without microscopic reticulations; right valve (with byssal notch) with about 18 to 21 primary, moderately scaled ribs which have 5 to 7 much smaller spined ribs between; left valve with about 10 to 11 primary, spined ribs which have a single, rounded, almost as large PECTINIDAE 365 secondary rib in between. Between these large ribs there are 15 to 18 tiny, spined ribs, 3 of which are on the large secondary rib. Color variable: solid rose, pink, white, light yellowish and blends of all these. Commonly dredged in shallow waters. Chlamys hindsi Dall Hinds’ Scallop Plate 341 Alaska to off San Diego, California. 2 to 2% inches in size; with microscopic reticulations between the ribs either near the beaks or the margins of the valves. Left valve (without the byssal notch) with numerous primary ribs, each bearing 3 rows of spines, and with a secondary spined rib between. Right valve flattish, usually lighter- colored, and with fewer ribs which are smoothish, rounded and inclined to be grouped in pairs. The reticulate sculpturing is best seen on this side. Color variable: light-rose, mauve, lemon-yellow, pale-orange and blends of these. A rather common species dredged in shallow water down to 822 fathoms. Chlamys islandica Miller Iceland Scallop Plate 27] Arctic Seas to Buzzards Bay, Massachusetts. Alaska to Puget Sound, Washington. 3 to 4 inches in length, not quite so wide. Long hinge ear is twice the length of the short one. Valves moderately convex to flattish. With about 50 coarse, irregular ribs which split in two near the margin of the valve. Rarely, the ribs are grouped more or less in groups of twos, threes or fours. Color usually a dirty-gray or cream, but some are quite attractively tinged with peach, yellow or purplish both inside and out. A very common species offshore on the continental shelf. Genus Leptopecten Verrill 1897 Leptopecten latiauratus Conrad Kelp-weed Scallop Plate 341 Point Reyes, California, to Lower California. About 1 inch in size, thin, lightweight, with 12 to 16 squarish ribs. Ears strongly pointed at the ends. Color varies from translucent yellowish to chestnut-brown; commonly mottled with white. The subspecies monotimeris Conrad has rounded ribs which form broad corrugations on the shell and it has less acutely pointed ears. This is a common species found attached to kelp weeds, stones and bottoms of boats. Sometimes spelled Jatiauritus. 366 American Seashells Genus Placopecten Verrill 1897 Placopecten magellanicus. Gmelin Atlantic Deep-sea Scallop Plates 33c; 27m Labrador to Cape Hatteras, North Carolina. 5 to 8 inches in size, almost circular. Valves almost flat to slightly convex. Interior flaky-white. Exterior rough with numerous very small, raised threads. Exterior yellowish gray to purplish gray or dirty-white. This is the common, edible, deep-sea scallop fished off our New England coasts. The name grandis Solander is nude and cannot be used. Genus Lyropecten Conrad 1862 Subgenus Lyropecten s. str. Lyropecten antillarum Recluz Antillean Scallop Plate 34g Southeast Florida and the West Indies. ¥% to %4 inch in length and width. Valves fragile, both nearly flat. Only about 15 moderately rounded, low ribs. Growth lines exceedingly fine (seen with the aid of a strong lens). Color either pastel-yellow, tawny- orange or light-brown, commonly with chalk-white mottlings, flecks or stripes. Found uncommonly in shallow water. Subgenus Nodipecten Dall 1898 Lyropecten nodosus Linné Lion’s Paw Plate 33b North Carolina to Florida and the West Indies. 3 to 6 inches in size, rather heavy and strong-shelled. Characterized by the 7 to g large, coarse ribs which have large, hollow nodules. The entire shell also has numerous, much smaller, but distinct, riblets. The color is commonly dark maroon-red, but may be bright-red or orange. Fairly com- mon offshore, especially on the west coast of Florida. Genus Aequipecten P. Fischer 1887 Subgenus Aequipecten s. str. Aequipecten glyptus Verrill Tyron’s Scallop Plate 33a South of Cape Cod to the Gulf of Mexico. 1 to 2% inches in size. Both valves rather flat. Shell somewhat lop- sided and spathate in shape. About 17 ribs which start out as fine, sharp, slightly prickled ribs, but become flattened and indistinct or absent near the PECTINIDAE 367 margin of the valve. One valve pure-white, the other with broad, rose rays corresponding to the ribs. Internally white and with weak, fine ribs. Rare, but has been brought in by commercial trawlers. This is P. tryoni Dall. Aequipecten phrygius Dall Spathate Scallop Off Cape Cod to east Florida and the West Indies. About 1 inch in size. Characterized by its peculiar spathate or open- fan shape. With 17 sharp ribs. On closer inspection, it will be seen that each rib is composed of 3 rows of very fine, closely packed scales which are welded together to form a single rib. In cross-section, this would give the rib the shape of the letter M. Hinge-line straight with one ear slightly shorter than the other. Color dull-gray with indistinct blotches of dull- pink. Uncommonly dredged off Miama and the Lower Keys. Aequipecten lineolaris Lamarck Wavy-lined Scallop Florida Keys to the Lesser Antilles. 1 to 2 inches in size, ears about equal. Valves moderately inflated. Sur- face highly glossy, the colored valve with about 18 very low, rounded ribs. Bottom valve white. Top valve rosy-tan with characteristic, numerous small, wavy, thin lines of pink-brown running concentrically. A few brown mot- tlings may be present. A very gorgeous and rare species dredged from 7 to 50 fathoms. A. mayaguezensis Dall and Simpson is this species. Aequipecten muscosus Wood Rough Scallop Plate 34d, e North Carolina to both sides of Florida and the West Indies. % to 174 inches in size, both valves inflated and fairly deep. Hinge-ears equal to the width of the main part of the shell. 18 to 20 ribs, the center part of each bearing prominent, erect, concave scales, and on each side 2 rows of much smaller scales. Color orange-brown, red, lemon-yellow, orange, or commonly mottled with purple. Beach-worn specimens may lose most of their scaliness. Moderately common just offshore to 90 fathoms. Formerly called exasperatus Sby, and fusco-purpureus Conrad. Subgenus Plagioctenium Dall 1898 Aequipecten irradians Lamarck Atlantic Bay Scallop Plate 331 Nova Scotia to northern half of Florida and Texas. 2 to 3 inches in size. This is the common edible scallop of our east 368 American Seashells coast. It is not a very colorful species, although its drab browns and grays are rarely enlivened with yellow. There are 3 distinct subspecies which previously have been little understood. Each has a distinct geographical range and peculiar habitat. A. irradians irradians Lamarck. Nova Scotia to Long Island, N.Y. 17 to 18 ribs which are low and roundish in cross-section. Each valve is about the same fatness, and the lower one is only slightly lighter in color. Drab gray-brown with indistinct, darker-brown mottlings. The most compressed of the 3 subspecies. This is borealis Say. A. irradians concentricus Say. New Jersey (rare), Virginia to Georgia and Louisiana to ‘Tampa, Florida. 19 to 21 ribs which are squarish in cross- section. Lower valve (the lightest in color and commonly all white) is much fatter than the dull bluish gray to brown upper valve. Common. A. irradians amplicostatus Dall (fig. 26f). Central Texas to Mexico and Colombia. Similar to concentricus, but with only 12 to 17 ribs; more gibbose; lower valve commonly white and with high, squarish to slightly rounded ribs. Common in Texas. Aequipecten gibbus Linné Calico Scallop Plate 33) North Carolina to Florida, the Gulf of Mexico, and West Indies. 1 to 2 inches. A common, colorful scallop found abundantly in southern Florida a little offshore. Both valves quite fat. Ribs usually 20 (19 to 21), quite square in cross-section. Bottom valve commonly whitish with a little color; upper valve can be of many bright hues (lavender-rose, red, whitish with purple or reddish mottlings, etc.). This is dislocatus Say. If collecting in southeast Florida, do not confuse with A, nucleus, Aequipecten gibbus nucleus Born Nucleus Scallop Plate 34h Southeast Florida and the West Indies. 1 to 1% inches in size. This is a difficult subspecies to identify, and it is possible that it is only a form. It is rarely over an inch in size, has 1 to 3 more ribs than gibbus, is usually fatter, and is characteristically colored with small, chestnut mottlings on a cream background and commonly with snow- white specklings. Both or only one valve may be heavily colored. Never with the bright shades of orange, red, etc. Not uncommon in the Keys from low tide to a few fathoms on grass, Genus Hinnites Defrance 1821 Biologically speaking, this genus is really a Chlamys in which the adults SPONDY LIDAE 369 are attached to rocks and become quite massive like Spondylus. For con- venience, we are considering it a full genus. Hinnites multirugosus Gale Giant Rock Scallop Plate 29a Aleutian Island to Lower California. Up to 8 inches in length. A heavy massive shell characterized by the early “Chlamys-like” shell at the beaks. Interior white with a purplish hinge area. Attached to rocks by the right valve. The 44-inch long young are almost impossible to separate from some species of Chlamys, except when they show a mauve spot on the inside of the hinge line on each side of the resilium pit, or if they show signs of distortion or a mottling pattern of color on the outside of the valves. Some young are bright-orange. A common species. Formerly known as Hinnites giganteus Gray. This is a regrettable name change which I have followed, since leading workers on the Pacific Coast have adopted it. Family PROPEAMUSSIIDAE Genus Propeamussium Gregorio 1883 Propeamussium pourtalesianum Dall Pourtales’ Glass Scallop Plate 27c Southeast Florida and the West Indies. % inch in length. Valves very slightly convex. Shell extremely thin and transparent (like thin mica flakes). Each valve reinforced inside with about 9 rod-like, opaque white ribs. Exterior of one valve is smoothish, the other valve with numerous, microscopic, concentric threads. Common off- shore. Frequently dredged off Miama by amateurs. There have been a number of other species described, some of which may only be forms of this variable species, Family SPONDYLIDAE Genus Spondylus Linné 1758 Spondylus americanus Hermann Atlantic Thorny Oyster Plate 36b South half of Florida and the West Indies. 3 to 4 inches in size. Spines 2 or less inches in length, usually standing fairly erect. Color variable: white with yellow unbones, red or purple; sometimes all rose, all cream or all pink. The young are much less spinose, and might be confused with Chama which, however, does not have the ball- and-socket type of hinge. Beautiful and large specimens are found clinging 370 American Seashells to old wrecks in fairly deep water. Perfect specimens have recently sold for over $40. Formerly called americanus Lamarck, echinatus Martyn and domi- nicensis Roding. Sometimes called the Chrysanthemum Shell. Not un- common. Spondylus pictorum Schreiber Pacific Thorny Oyster Plate 36 Gulf of California to Panama. a Up to 5 inches in size. The spines are 1% inches or less in length and usually bent over. Color variable, and usually more brilliant than the Atlantic species. A popular, and now fairly high-priced collector’s item. Often found on beaches with their spines worn off. They live in fairly deep water at- tached to rocks and wrecks. Family LIMIDAE Genus Lima Bruguiere 1797 Lima lima Linné Spiny Lima Plate 35¢ Southeast Florida and the West Indies. 1 to 1% inches in height and pure-white in color. Sculpture of numer- ous even, radial ribs bearing many erect, sharp spines. The posterior ear is much smaller than the anterior one. No large posterior byssal gape as in scabra. Moderately common under coral stones in shallow water. This species and its various forms or subspecies (squamosa Lamarck, multicostata Sowerby, caribaea Orbigny and tetrica Gould) are found all over the world in tropical waters, Lima pellucida C. B. Adams Antillean Lima North Carolina to both sides of Florida and the West Indies. % to 1 inch in height, elongate, fragile, semi-translucent, white, with a large posterior gape and with a long, narrow anterior gape. Radial ribs small, fine, uneven in size and distribution. Hinge-ears almost equal in length. Closely related to L. bians Gmelin from Europe. A fairly common species which is often misidentified in collections as L. inflata Lamarck (not Gmelin). L. antillensis Dall is the same. In thicker and older specimens there is a small, pinhole depression in the hinge just off to one side of the ligamental area. Subgenus Ctenoides Morch 1853 Lima scabra Born Rough Lima Plate 35f, o Southeast Florida and the West Indies. ANOMIIDAE 371 1 to 3 inches in height, half as long. Sculpture coarse, consisting of ir- regular, radial rows of short, bar-like ribs, somewhat giving the appearance of shingles on a roof. Periostracum thin, dark- to light-brown. A common variation of this species (form tenera Sowerby) is startlingly different, in that the small radial ribs are much more numerous and much smaller (pl. 35h), Common under rocks in shallow water at low tide. Subgenus Mantellum Roding 1798 Lima hemphilli Hertlein and Strong Hemphill’s Lima Plate 29c Monterey, California, to Mexico. 1 inch in length, white, obliquely elliptical in shape. With fine, irreg- ular, radial ribs which are crossed by very fine, rough threads. Anterior and posterior margins smooth. This fairly common species has been erroneously called dehiscens Conrad and L. orientalis Adams and Reeve. Genus Limatula Wood 1839 Limatula subauriculata Montagu Small-eared Lima Greenland to Puerto Rico. Alaska to Mexico. % inch in height, ovate-oblong, greatly inflated (having the shape of the shell of a pistachio nut), and sculptured with numerous small, longitudi- nal riblets. On the inside of the valves there are 2 prominent, longitudinal riblets at the center of the shell. Periostracum over the white shell is yel- lowish brown. Moderately common in cooler waters from just offshore to 1000 fathoms. Genus Limea Bronn 1831 Limea bronniana Dall Bronn’s Dwarf Lima North Carolina to Florida and the West Indies. Very small, 5.0 mm. in height, ovate, superficially resembling a small Cardium. With about 25 to 30 strong, smooth, rounded, radial ribs. Micro- scopic, concentric scratches between the ribs. Inner margin of valves serrated and reinforced by small, round teeth. Shell pure-white in color. Hinge-ears with an internal set of 3 or 4 small teeth. Superfamily ANOMIACEA Family ANOMIIDAE Genus Anomia Linné 1758 The valve without the hole has 1 large and 2 small muscle scars. The 372 American Seashells shell is attached to a rock or wood surface by means of a calcified byssus which passes through a large notch in the right valve. The genus Pododes- mus differs in having only 2 muscle scars in the top or holeless valve. Anomia simplex Orbigny Common Jingle Shell Plate 35k Cape Cod to Florida, the Gulf of Mexico, and the West Indies. 1 to 2 inches in size, irregularly oval, smoothish, thin but strong. The upper or free valve is usually quite convex; the lower valve is flattish and with a hole near the apex. Color either translucent-yellow or dull-orange. Some with a silvery sheen. Specimens buried in mud become blackened. Very commonly attached to logs, wharfs and boats. Anomia aculeata Gmelin Prickly Jingle Shell Nova Scotia to North Carolina. Rarely exceeding *4 inch in size, irregularly rounded, moderately fragile. Upper valve convex, rough, often with small prickles. Lower valve flat and with a small hole near the hinge end. Color drab, opaque whitish tan. A common cold-water species attaching itself to rocks and broken shells. Anomia peruviana Orbigny Peruvian Jingle Shell Plate 29e San Pedro, California, to Peru. 1 to 2 inches in size, variable in shape, thin, partially translucent, smooth or with irregular sculpture; colored orange or yellowish green. Occurs be- tween tides attached to rocks, other shells and waterlogged wood. Common. Genus Pododesmus Philippi 1837 The valve without the hole has 1 large and 1 small muscle scar. Pododesmus macroschismus Deshayes False Jingle Shell Plate 29d Alaska to Lower California. 1 to 4 inches in size. Radiating ribs very irregular and coarse. Color yellowish or greenish white, inner surface green and somewhat pearly. Lower valve with a large opening for the byssus. This is a very common species which is found attached to stones and wharf pilings from low-tide mark to about 35 fathoms. Often found on Haliotis. P. cepio Gray is a synonym. Pododesmus rudis Broderip from Florida and the West Indies is very OSTREIDAE 373 similar to the Pacific Coast species. Inch-long, brownish specimens are found in the crevices of coral boulders below low-water mark to several fathoms. Larger, more whitish specimens are found clinging to iron wrecks. Moder- ately common, P, decipiens Philippi. See plate 38b. Superfamily OSTREACEA Family OSTREIDAE Genus Ostrea Linné 1758 This genus used to include all of the oysters, but today several valid genera are recognized, so that only three American species are included in true Ostrea. These are O. equestris Say and O. permollis Sowerby from the Atlantic Coast and O. Jurida Carpenter from the Pacific Coast. The Euro- pean oyster, O. edulis Linné is also in this group. All of these oysters are relatively small. The eggs are fertilized and developed within the mantle chamber and gills. Usually around one million eggs are produced at one spawning. The prodissoconch hinge is long, the valves symmetrical. In the adults, the muscle scar is near the center of the shell and is not colored. Ostrea equestris Say Crested Oyster Plate 28c North Carolina, Florida, the Gulf States and West Indies. 1 to 2 inches in length, more or less oval, and with raised margins which are crenulated. The attached valve has a flat interior with a rather high, ver- tical margin on one side. Interior dull grayish with a greenish or opalescent- brown stain. Margin sometimes stained a weak-violet. Not very abundant except in some Florida bays. It lives in water that is much saltier than that in which virginica lives. Also named spreta Orbigny. O. cristata Born 1s quite different and is limited to South America, Ostrea frons Linné ‘Coon Oyster Plate 28d Florida, Louisiana and the West Indies. 1 to 2 inches in size. The radial plicate sculpture and corresponding sharply folded valve margins are characteristic of this intertidal species. Inner margins of valves closely dotted with minute pimples for nearly the entire circumference of the valves. Muscle scars located well up toward the hinge. Beaks somewhat curved. Interior translucent-white, exterior usually purplish red. Frequently elongate and attached to stems of trees by a series of clasp- ing projections of the shell, but may be also oval in shape. O. rubella and O. limacella Lamarck are this species. O. folium Linné is a Philippine species. 374 American Seashells Ostrea permollis Sowerby Sponge Oyster Plate 28b North Carolina to Florida and the West Indies. Rarely over 3 inches in size. Lives embedded in sponges with only the margins of the valves showing. The surface of the valves has a soft, silky appearance. Beak twisted back into a strong spiral. Exterior light-orange to tan; interior white. Inner margins with numerous small, round denticles. Common. Another flat, but larger and light-shelled oyster, Pycnodonta hyotis Linné, is found in deep water attached to old wrecks off Florida and in the West Indies. It is immediately recognized by the peculiar structure of the shell which under a lens appears to be filled with numerous bubbles or empty cells, much like a bath sponge. It reaches a diameter of 3 or 4 inches, is generally circular in outline and may be colored whitish cream, brownish or even lavender. Ostrea thomasi McLean is this species according to the French worker, Gilbert Ranson, Ostrea lurida Carpenter Native Pacific Oyster Plate 2of Alaska to Lower California. 2 to 3 inches in length, of various shapes; generally rough with coarse concentric growth lines, but sometimes smoothish. Interior usually stained with various shades of olive-green, and sometimes with a slight metallic sheen. It occasionally has purplish brown to brown axial color bands on the exterior. This is the common intertidal native species of the Pacific Coast. A number of ecological forms have been described: expansa Carpenter, rufoides Cpr. and possibly conchaphila Cpr. Genus Crassostrea Sacco 1897 This genus includes the commercially important American Oyster, C. virginica Gmelin, which was formerly placed in the genus Ostrea. In Crassostrea, the left or attached valve is larger than the right. The inner margin is smooth. The eggs are small, produced in large numbers at one spawning (over 50 million), and are fertilized and develop in the open wa- ters outside of the parents. The muscle scar is usually colored. The prodisso- conch hinge is short, and the valves asymmetrical. The Japanese Oyster (C. gigas), introduced to west American shores, the Portuguese Oyster (C. angu- lata Lamarck), and C. rhizophorae Guilding from Cuba also belong to this genus. Gryphaea Lamarck is a fossil genus which should not be associated with this genus. SS ASTARTIDAE Se) Crassostrea virginica Gmelin Eastern Oyster Plate 28a Gulf of St. Lawrence to the Gulf of Mexico and the West Indies. 2 to 6 inches in length. This is the familiar edible oyster which varies greatly in size and shape. The valve margins are only slightly undulating or are straight. The muscle scar is usually colored a deep purple, the rest of the shell being white inside and dirty-gray exteriorly. Beaks usually long and strongly curved. “Blue Points,” a form originally harvested at Blue Point, Long Island, are rounded in shape and with a rather deep, lower valve. “Lynnhavens” are broad, elongate forms originally harvested at Lynnhaven Bay, Virginia. These variations are due to environmental differences. C. brasiliana Lamarck and C. floridensis Sowerby are this species. Crassostrea rhizophorae Guilding (brasiliana of authors) is found in the Caribbean region, and it is a lightweight shell, deep-cupped, with a flat upper valve small and fitting well down into the lower valve. The inner margin of the lower, attached valve is splotched with bluish purple. Common. Crassostrea gigas Thunberg Giant Pacific Oyster Plate 29g British Columbia to California. Japan. 3 to 12 inches in length, of various shapes, but generally characterized by its large size, its coarse, widely spaced, concentric lamellae or very coarse longitudinal flutings or ridges on the outside. Interior enamel white, often with a faint purplish stain on the muscle scar or near the edges of the shell. Very rarely with a greenish stain. A common, large and marketable oyster introduced yearly into Canada and the United States from Japan. The form laperousi Schrenck is round. The typical gigas is the long, strap-like form. O. gigas Meuschen is an invalid name and does not preoccupy that of Thun- berg’s. Also known as the Japanese Oyster. Order EULAMELLIBRANCHIA Suborder HETERODONTA Superfamily ASTARTACEA Family ASTARTIDAE Genus Astarte Sowerby 1816 Astarte borealis Schumacher Boreal Astarte Plate 28q Arctic Seas to Massachusetts Bay. Alaska. 1 to 2 inches in length, ovate, moderately compressed. External liga- ment large. Concentric ridges strong near the beaks but disappearing near 376 American Seashells the margins of the valves. Differing from swbequilatera in being more ellip- tical in side view, in having the beaks near the middle, with weaker con- centric ribs, and with the inner surface of the valve margins smooth. A com- mon shallow-water species. Astarte subequilatera Sowerby Lentil Astarte Plate 28-0 Arctic Seas to off Florida. 1 to 1% inches in length, ovate, moderately compressed. External liga- ment small. Concentric ridges strong, rounded, evenly spaced. Internal mar- gin of valves finely crenulate. Beaks turned slightly forward, often eroded. Color dull light- to dark-brown. Found in shallow water in the north and below 50 fathoms in the south. Common, Compare with borealis. Astarte undata Gould Waved Astarte Plate 28r New Brunswick to Maine. Similar to subequilatera, but less elliptical, with its beaks near the center and with fewer and stronger concentric ridges. Probably the commonest Astarte in New England. Astarte castanea Say Smooth Astarte Plate 28s Nova Scotia to Cape Cod. 1 inch in length, as high, trigonal in shape, quite compressed. Beaks pointed and hooked anteriorly; external ligament small. Shell almost smooth, except for weak, low concentric lines. Color a glossy light-brown. Inner margin of valves finely crenulate. A commonly dredged species. Astarte nana Dall Southern Dwarf Astarte North Carolina to Florida and the Gulf States. % inch in length, slightly trigonal in shape, compressed. With or with- out about 25 well-developed, evenly spaced, rounded, concentric ridges. Ventral and inner edge of valves usually with 40 to 50 distinct small pits or crenulations. Shell cream, tan, brown or rose-brown in color with the beaks usually whitish. A very abundant species dredged in moderately shallow water, especially off eastern Florida. Family CRASSATELLIDAE Genus Eucrassatella Iredale 1924 Shell large, thick, equivalve, posteriorly rostrate; ligament and resilium CRASSATELLIDAE 377 adjacent and internal in a triangular resilifer; left valve with 2 diverging cardi- nal teeth; right valve with 3, of which the posterior one is more or less obso- lete. 3 laterals in each valve. Crassatella Lamarck is fossil and not this genus. Crassatellites Krueger is believed to be invalid. Eucrassatella speciosa A. Adams 1852 Gibb’s Clam Plate 30z North Carolina to both sides of Florida and the West Indies. 1% to 2% inches in length, 7% as high, heavy, beaks at the center, and the shell somewhat diamond-shaped. Concentric sculpture of neat, rather heavy, closely packed ridges (about 15 per half inch). Lunule and escutcheon sunken, lanceolate in shape and about the same size as each other. Exterior with a thin, persistent, nut-brown periostracum. Interior glossy ivory with either a tan or pink blush. Moderately common just offshore in sand. C. floridana Dall is the same, being based on a young specimen. E. gibbesi Tuomey and Holmes 1856 is a synonym. Genus Crassinella Guppy 1874 Shell small, compressed, subtriangular, and slightly inequivalve. 2 cardi- nals in each valve. 1 anterior lateral in the right valve, 1 posterior lateral in the left valve. Crassinella lunulata Conrad Lunate Crassinella Figure 28k North Carolina to both sides of Florida and the West Indies. ¥% to % inch in length, as high, quite compressed, solid, with the tiny, closely pressed-together beaks at the middle or slightly toward the anterior end. Dorsal margins straight and about go degrees to each other, the anterior margin slightly longer and with a wider sunken area. The valves are pecu- liarly askew, so that the posterior dorsal margin of the left valve is more obvious than that of the right valve. Concentric sculpture of coarse but well- developed ribs (about 15 to 17 plainly visible). Color whitish or pinkish, interior commonly brown. Sometimes faintly rayed. A common shell from beach to 60 fathoms. Crassinella mactracea Lindsley Lindsley’s Crassinella Plate 30b Massachusetts Bay to Long Island, New York. Almost identical with Junulata from more southern waters, but more obese, with a more oval lunule, and generally with a chalky texture to the 378 American Seashells shell. Occasionally the ribs are less strongly developed. Common from just offshore to 30 fathoms. Superfamily CARDITACEA Family CARDITIDAE Genus Cardita Bruguiere, 1792 Shell small, thick, radially ribbed, quadrate, with a slight ventral gape and having a byssus. The animal has a marsupium to contain its eggs. Pos- terior right cardinal usually absent or almost so. This appears to be the accepted use of Cardita according to Winckworth, Chavan, Lamy and Dall. Subgenus Carditamera Conrad 1838 Carditamera has shells which are more elongate and have strong lateral teeth. Cardita floridana Conrad Broad-ribbed Cardita Plate 30a Southern half of Florida and Mexico. 1 to 1% inches in length, about half as high, elongate, inflated, solid and heavy. Surface with about 20 strong, Lodnidedl raised, beaded, radial ribs. In live material, the gray periostracum obscures the color of the shell. Ex- terior whitish to gray with small bars of chestnut color on the ribs arranged in concentric series. Interior white with a small light-brown patch above the two muscle scars. Beaks close together. Lunule small, very deeply in- dented under the beaks. Ligament moderately large, visible from the out- side. Very common on the west coast of Florida where it is washed ashore. Used extensively in the jewelry business. Cardita gracilis Shuttleworth is doubtfully recorded from Florida but is known from Mexico to Puerto Rico. It is quite elongate, narrow at the anterior end, with larger, smoothish ribs, and the posterior lateral tooth is stained dark-brown. Uncommon. The Pacific Coast species is Cardita carpenter Lamy (pl. 29r) which is % inch long and ranges from British Columbia to Lower California in shal- low to deep water. Its color is brownish gray with a purplish interior. Subgenus Glans Mihlfeld 1811 Cardita dominguensis Orbigny Domingo Cardita North Carolina to southeastern Florida. Y% inch in length, ovate, inflated; beaks close together, pointing toward CARDITIDAE 379 each other, located nearer the anterior end. Lunule narrow, rough, ill- defined. Numerous strong radial ribs are weakly beaded. Color whitish with a rose tint. Moderately common from 1 foot to 70 fathoms on sandy bot- toms. Compare with the commoner and closely resembling Venericardia tridentata. Genus Venericardia Lamarck 1801 Shell rounded-trigonal, with strong radial ribs which are commonly beaded; internal margins crenulate; right anterior cardinal and laterals absent. No byssus made. Subgenus Cyclocardia Conrad 1867 Cyclocardia has whitish shells and a rough periostracum. Venericardia borealis Conrad Northern Cardita Plate 28t Labrador to Cape Hatteras. 1 to 1% inches in height, rounded, obliquely heart-shaped, thick and strong; beaks elevated and turned forward. Surface with about 20 rounded, moderately rough or beaded, radial ribs. Shell white, usually covered by a fairly thick, velvety, rusty-brown periostracum. Lunule small but very deeply sunk. Hinge strong; in the left valve the central tooth under the beak is large, triangular and curved. Very common on the Grand Banks where it serves as a food for fish. V. novangliae Morse (Nova Scotia to New York) is similar, but is ovate, the length being slightly greater than the height of the shell. It is sometimes considered a variety of borealis. Venericardia ventricosa Gould Stout Cardita Plate 29] Puget Sound to Santa Barbara Islands. About % inch in length, rounded-trigonal, moderately fat, lunule small; with about 13 rather wide, radial ribs which are bluntly beaded. Inner mar- gins of the valves have prominent, squarish, widely spaced crenulations which correspond to the external ribs. There are two other forms, one from Mon- terey (stearnsi Dall), the other from Redondo Beach, which are very close, but their distinctiveness and proper names are yet to be decided. The latter form is V. redondoensis “Burch” P. Morris 1952. C. ventricosa is dredged fairly commonly. 380 American Seashells Subgenus Plewromeris Conrad 1867 Venericardia tridentata Sa Three-toothed Cardita yy North Carolina to all of Florida. ¥% inch in length and height, trigonal in shape, inflated, with 15 to 18 heavily beaded strong radial ribs. Beaks close together, pointing slightly forward. Lunule oval, sharply impressed, smoothish. Escutcheon small, nar- row. External color grayish brown, sometimes with red-brown mottlings. Hinge-teeth often purplish blue. Interior of valve stained with light-brown on white background. A common, moderately shallow-water species, usually confused with Cardita dominguensis which, however, lacks the strong tri- dentate hinge, is ovate in shape, whose ribs are weakly beaded and whose beaks point toward each other. Venericardia perplana Conrad Flattened Cardita Plate 28] North Carolina to southern half of Florida. ¥% inch in size, similar to V. borealis but much smaller, without a peri- ostracum, pinkish or mottled brown, and more oblique. The ribs are wider, and close to each other. The subspecies flabella Conrad from Tampa Bay, Florida, has fewer ribs which are squarish and separated by furrows almost equal in size to the ribs themselves. V. perplana is common, flabella only locally found at certain seasons in few numbers. Figure 76. Kelsey’s Milner Clam, Milneria kelseyi Dall, % to %4 inch (southern California). Genus Milneria Dall 1881 Milneria kelseyi Dall Kelsey’s Milner Clam Figure 76 Monterey to Lower California. % to % inch in length. An extraordinary clam which resembles a tiny Brazil nut. The bottom margins of the valves are pushed in to form a small cup-shaped hollow. Into this, the females put the 50 or so young whose ARCTICIDAE 381 shells are smooth and round. The hollow is covered over by a sheath of peri- ostracum. Hinge of adult with large triangular tooth in left valve which fits snugly between two smaller ones in the right valve. Found in shallow water under stones. External sculpture of scaled ribs and concentric ridges. Color light-brown. Shell thick, translucent glaze inside. Family CORBICULIDAE Genus Polymesoda Rafinesque 1820 Polymesoda caroliniana Bosc Carolina Marsh Clam Plate 30bb Virginia to north half of Florida and Texas. 1 to 1¥%4 inches in length, about as high, subtriangular in outline, rather obese and with a strong shell. Exterior of smoothish shell is covered with a very fuzzy or minutely scaled periostracum which is mostly glossy-brown and rather thin. Interior white, rarely stained with purple. Each hinge with 3 small, almost vertical, equally sized teeth below the beaks and each hinge with 1 anterior and posterior lateral. Ligament external, long, narrow and dark-brown. Common at the mouths of rivers where the influence of the tides is felt. Genus Pseudocyrena Bourguignat 1854 Pseudocyrena floridana Conrad Florida Marsh Clam Plate 30y Key West to northern Florida and to Texas. 1 inch in length, quite similar to Polymesoda caroliniana, but more vari- able in shape (ovalish to elongate), without the fuzzy periostracum, with its beaks never eroded away and with 2 long, slender anterior and posterior laterals. Exterior with irregular growth lines, dull dirty-white, commonly flushed with purple or pink. Interior white with a wide margin of deep purple or entirely purple. Brackish warm water in mud. Common. Family ARCTICIDAE Genus Arctica Schumacher 1817 (Cyprina Lamarck) Arctica islandica Linné Ocean Quahog Plate 328 Newfoundland to off Cape Hatteras, North Carolina. 3 to 5 inches in length, almost circular in outline, rather strong, porcel- laneous, but commonly chalky. Exterior covered with a brown to black, rather thick periostracum. The posterior laterals and the absence of a pallial 382 American Seashells sinus will distinguish this clam from the true Quahogs (see Mercenaria mercenaria). A common, commercially dredged species found in sandy mud from 5 to 80 fathoms. This is the only living species in this family. There are numerous fossil species. Also called the Black Clam and Mahogany Clam. Family TRAPEZIIDAE Genus Coralliophaga Blainville 1824 Shell cigar-shaped, with the beaks at the anterior end. 3 cardinals in each valve, the posterior one extending along the hinge line like a lateral. Posterior muscle scar considerably larger than the anterior one. Some work- ers have placed this genus in the Petricolidae. Coralliophaga coralliophaga Gmelin Coral-boring Clam Plate 28p West coast of Florida to Texas and the West Indies. % to 1% inches in length, oblong to elongate, and quite thin. Very finely sculptured with radial threads. Concentric lamellations present at the posterior end. Exterior yellowish white; interior white. This shell is very similar in appearance to Lithophaga antillarum, but may be told from it by the presence of distinct teeth in the hinge. This is an uncommon species which lives in the burrows of other rock-boring mollusks. Superfamily DREISSENACEA Family DREISSENIDAE Genus Congeria Partsch 1835 Subgenus Mytilopsis Conrad 1857 Congeria leucophaeata Conrad Conrad’s False Mussel New York to Florida to Texas and Mexico. ¥% to *4 inch in length, superficially resembling a Mytilus or Septifer because of its mussel-like shape. The Septifer-like shelf at the beak end has a tiny, downwardly projecting, triangular tooth on the side facing the long, internal ligament. The hinge has a long thin bar under the ligament. Exte- rior bluish brown to tan with a thin, somewhat glossy periostracum. Interior dirty bluish tan. This common bivalve attaches itself by its short byssus to rocks and twigs in clumps which resemble colonies of Mytilus. Found in brackish to fresh water near rivers. DIPLODONTIDAE | 383 Superfamily LUCINACEA Family DIPLODONTIDAE Genus Diplodonta Bronn 1831 Shell thin, orbicular and strongly inflated. There are 2 cardinal teeth in each valve. The left anterior and right posterior ones are split or bifid. Lat- erals obscure or absent. Taras Risso, commonly used in place of the name Diplodonta, 1s a doubtful name which has been recently abandoned. Subgenus Diplodonta s. str. Diplodonta punctata Say Common Atlantic Diplodon North Carolina to both sides of Florida and the West Indies. 4% to % inch in length, moderately strong, almost orbicular, well-inflated and pure-white in color. Smooth near the beaks, elsewhere very finely scratched with concentric lines and commonly with distantly spaced, coarse growth lines. Fairly common in shallow to deep water. Diplodonta orbella Gould Pacific Orb Diplodon Alaska to Panama. %4 to 1 inch in length, almost circular in outline, quite inflated and smoothish except for moderately coarse growth lines. Beaks small, pointing slightly forward. Ligament posterior to beaks is long, raised and conspicuous. 2 rather large teeth in each valve below the beaks. Left anterior and right posterior teeth split. In many shallow-water localities, this clam builds a compact nest of periostracal material and detritus. In its more southerly range, specimens are usually more compressed, less orbicular in shape and more glossy externally (subspecies swbquadrata Carpenter). Alias Taras or- bella. Subgenus Phlyctiderma Dall 1899 Diplodonta semiaspera Philippi Pimpled Diplodon North Carolina to Florida, Texas and the West Indies. Rarely over ¥% inch in length, similar to D. punctata, but chalky-white externally and with numerous concentric rows of microscopic pimples. Mod- erately common in sand below low-water mark to 4o fathoms. Alias D. granulosa C. B. Adams. 384 American Seashells Subfamily THY ASIRINAE Genus Thyasira Lamarck 1818 Shell subglobular and of an earthy texture; umbones directed forward; posterior region of valve deeply furrowed; lunule absent; ligament in a groove and partly external; hinge without teeth and indented in front of the umbo; pallial line without a sinus. Thyasira trisinuata Orbigny Atlantic Cleft Clam Nova Scotia to south half of Florida and the West Indies. Y%4 to % inch in length, oblong, fragile and translucent-white. Hinge weak and with only a very long, weak posterior lateral. Posterior slope of shell with 2 strong, radial waves or rounded grooves. Moderately common in dredgings from 15 to go fathoms on sandy bottom. Thyasira gouldi Philippi (Labrador to off North Carolina) is similar, but only % inch in size, almost round but slightly higher, and with a weak yel- lowish periostracum. The hinge lacks teeth. Common offshore to 60 fath- Called Gould’s Cleft Clam. ZZ i iy yy i) a . Yr ty ye Y) iti YY Z Za LT Figure 77. Pacific Cleft Clams. a, Thyasira bisecta Conrad, 1 inch (Pacific Coast); b and c, Thyasira excavata Dall, % inch (Gulf of California). Thyasira bisecta Conrad Pacific Cleft Clam Figure 77a Alaska to Oregon. 1 to 1% inches in length, almost square in side view and moderately obese. Characterized by the almost vertical, straight, anterior end which 1s go degrees to the dorsal margin. Ligament long and narrow and flush with the dorsal margin of the shell. There is a deep, prominent radial furrow on the exterior running posteriorly from the beaks, Shell chalky-white, com- LUCINIDAE 385 monly with a thin, yellowish gray periostracum. Irregular coarse growth lines present. Uncommon from 4 to 139 fathoms. Closely related to T. dis- juncta Gabb, if not that species. Family LUCINIDAE Genus Lucina Bruguiere 1797 Shell orbicular, strong and laterally compressed. Cardinal teeth small, obscure in the adults, but the laterals are well-developed. The use of Lucina here is based on Anton’s designation of pensylvanica Linné as the genotype. The genus Linga Gregorio is this genus. Subgenus Lucina s. str. Lucina pensylvanica Linné Pennsylvania Lucina Plate 38h North Carolina to south Florida and the West Indies. 1 to 2 inches in length, ovate, usually quite inflated. Concentric ridges very delicate and distinct. Color pure-white with a thin yellowish periostra- cum. Lunule heart-shaped, well-marked and raised at the center. The fur- row from the beak to the posterior ventral edge of the valve is very pro- nounced. Beachworm specimens become smooth and shiny-white. The species name was incorrectly spelled by Linné. Moderately common in shal- low water. Subgenus Here Gabb 1866 Lucina sombrerensis Dall Sombrero Lucina Figure 78b Southern Florida. % inch in length, oval, greatly inflated and pure white in color. No radial sculpture. Concentric riblets numerous, sharp and irregularly crowded. Concentric growth irregularities commonly make the outer surface wavy. Commonly dredged off Miami from 20 to go fathoms. Subgenus Bellucina Dall 1901 Lucina amiantus Dall Lovely Miniature Lucina Figure 78c North Carolina to both sides of Florida. ¥% to % inch in length, not quite so high, quite obese, thick-shelled, pure- white in color and beautifully sculptured with 8 to 9 wide, rounded, radial ribs across which run numerous, small concentric riblets. Near the posterior upper margin of the shell there is a radial row of about 8 to 11 small, scale- 386 American Seashells like nodes. Behind the tiny, curved beaks there is an ovalish, heart-shaped depression. Internal margin of valves strongly crenulated with tiny teeth. Adults are commonly misshapen by concentric growth stops. Common from shallow water to 68 fathoms. Compare with L. multilineata. Figure 78. American Lucinas. ATLANTIC: a, Phacoides filosus Stimpson, 1 to 3 inches; b, Lucina sombrerensis Dall, 4 inch; ec, Lucina amiantus Dall, %% inch; d and e, Lucina leucocyma Dall, % inch; f, Lucina multilineata Toumey and Holmes, % inch. PACIFIC: g, Lucina approximata Dall, %4 inch; h, Lucina tenui- sculpta Cpr., % inch. Subgenus Parvilucina Dall 1901 Lucina multilineata Yuomey and Holmes Many-lined Lucina Figure 78f North Carolina to both sides of Florida. ¥8 to 4 inch in length, almost circular in shape, very obese, moderately LUCINIDAE 387 thick-shelled, white, and very finely sculptured. Somewhat like L. amiantus, but without radial ribs, except for exceedingly fine threads seen best near the beaks. Concentric sculpture of numerous, rather irregular, growth threads. The shell commonly continues growth after a long rest, thus caus- ing an irregular, concentric hump in the shell. Inner margin very finely denticulate. P. crenella Dall is the same species. Common from beach to 120 fathoms, Lucina tenuisculpta Carpenter Fine-lined Lucina Figure 78h Bering Sea to Lower California. % inch in length, slightly less in height, oval in outline, chalky-white and with a thin, grayish or yellowish green periostracum. Sculpture of nu- merous, small, weak, raised, radial threads. Concentric growth lines fine and irregularly placed. Beaks fairly prominent and pressed closely together. Be- hind them, the narrow, depressed ligament is visible from the outside. In front is the small, heart-shaped, depressed lunule. Inner margin of valves finely toothed. Common just offshore, Lucina approximata Dall Approximate Lucina Figure 78g Monterey, California, to Panama. % inch or less in size. Very similar to tenuisculpta, but smaller, almost round in outline, more inflated and with fewer and quite strong, radial rib- lets. Periostracum very thin, commonly worn off. Shell texture less chalky. Common in sandy mud just offshore to 48 fathoms. Subgenus Plewrolucina Dall 1901 Lucina leucocyma Dall Four-ribbed Lucina Figure 78d, e North Carolina to southeast Florida and the Bahamas. % inch in length, roughly oval, fairly thick-shelled, inflated and white in color. With 4 conspicuous, large, rounded, radial ribs, and with numerous, small, crowded, squarish, concentric riblets. The inner margins of the valves are finely denticulate. A common, bizarrely sculptured species found from low water to several fathoms. Subgenus Pseudomiultha P. Fischer 1885 Lucina floridana Conrad Florida Lucina Plates 38i, 30aa West coast of Florida to Texas. 388 American Seashells 1% inches in length, almost circular, compressed, smoothish, except for a few weak, irregular growth lines. Pure-white with a dull-whitish, flaky periostracum. The beaks point forward, and in front of them there is a deep, small pit. Hinge plate fairly wide and strong, but the teeth are weakly de- fined. Moderately common in shallow water to a few fathoms, Genus Phacoides Gray 1847 Shell orbicular, quite compressed. Sculpture mostly concentric. Cardi- nal teeth obsolete in adults, but the laterals are well-developed. Phacoides Blainville is the same but is not considered valid. Dentilucina Fischer is the same. Subgenus Phacoides s. str. Phacoides pectinatus Gmelin Thick Lucina Plate 38g North Carolina to Florida, Texas and the West Indies. 1 to 2% inches in length, ovate, compressed, white or flushed with bright-orange. Concentric ridges moderately sharp, usually unequally spaced. Ligament partially visible from the outside. Lunule strongly raised into a rather thin, rough blade. Anterior and posterior lateral tooth strong. Cardi- nals very weak. Moderately common in shallow water. Alias Lucina ja- maicensis Lamarck. Do not confuse with P. filosus, Subgenus Lucinisca Dall 1901 Phacoides nassula Conrad Woven Lucina North Carolina to Florida, Texas and the Bahamas. % inch in length, almost circular, inflated, strong and pure white. Sculp- ture of strong, closely spaced, concentric and radial ribs. These form a reticulate, rough surface. Where the ribs cross each other there is a tiny, raised scale. The ventral margin of the valve is strongly beaded by the distal ends of the axial riblets. Common in shallow water to 100 fathoms. Phacoides nuttalli Conrad Nuttall’s Lucina Plate 31g Santa Barbara, California, to Manzanillo, Mexico. 1 inch in length, circular, moderately inflated and with a fine, sharp, cancellate sculpturing. The shell is divided off at the anterior and upper portion into a slightly more compressed region which is less sculptured con- centrically. Lunule very deep, short and larger in the left valve. Moderately common offshore in sand. LUCINIDAE 389 The subspecies centrifuga Dall, from Lower California, has stronger and distantly spaced, concentric, raised lines. Subgenus Lucinoma Dall 1901 Phacoides filosus Stimpson Northeast Lucina Plate 38); figure 78a Newfoundland to north Florida and the Gulf States. 1 to 3 inches in length (south of North Carolina rarely over 1% inches), almost circular, compressed, white, with a thin, yellowish periostracum. Beaks small, close together and centrally located. Sculpture of sharp, raised, thin, concentric ridges each about % inch apart. The young commonly lack these ridges. No anterior lateral tooth present. Common offshore. Do not confuse with pectinatus which has a strong anterior lateral tooth, is tinted inside with orange and whose concentric ridges are unevenly spaced. Phacoides annulatus Reeve Western Ringed Lucina Figure 28f Alaska to southern California. 2 to 2% inches in length, oval to circular and slightly inflated. With strongly raised, concentric threads about 4¢ inch apart. Shell chalky-gray to white, overlaid by a thin, greenish-brown periostracum. Fairly commonly dredged from 8 to 75 fathoms. The Tertiary fossil species acutilineatus Con- rad may be the same. Genus Anodontia Link 1807 Shell large, obese, fairly thin and subcircular in outline. Hinge without distinct teeth. Anterior muscle scar long and parallels the pallial line. Anodontia alba Link Buttercup Lucina Plate 38f North Carolina to Florida, the Gulf States and West Indies. 1% to 2 inches in length, oval to circular, inflated and fairly strong. Hinge with very weak teeth, the posterior lateral being the most distinct. Exterior dull-white with weak, irregular concentric growth lines. Interior with a strong blush of yellowish orange. A common species used in the shellcraft business. This is Lucina chrysostoma Philippi. Anodontia philippiana Reeve Chalky Buttercup Plate 38e North Carolina to east Florida, Cuba and Bermuda. 390 American Seashells 2 to 4 inches in length, very similar to A. alba, but with a more chalky shell, never with orange color, interior usually pustulose, and the long, an- terior muscle scar juts away from the pallial line at an angle of about 30 degrees instead of paralleling it as in a/ba. An uncommon species, commonly confused with alba. It lives down to 50 fathoms but at times is washed ashore. A, schrammi Crosse is this species. Genus Codakia Scopoli 1777 Shell large, orbicular, moderately compressed. Hinge of right valve with a prominent anterior lateral which is typically close to the cardinals (an an- terior, a posterior and a middle cardinal). Hinge of left valve with a large double anterior lateral, only 2 cardinals, and with a small, double posterior lateral, Subgenus Codakia s. str. Codakia orbicularis Linné Tiger Lucina Plate 38d Florida to Texas and the West Indies. 2% to 3% inches in length, slightly less in height, well-compressed, more or less orbicular in outline, thick and strong. Beaks and % inch of subsequent growth smoothish. Remainder of the shell roughly sculptured by numerous coarse radial threads which are crossed by finer concentric threads. This commonly gives the radial ribs a beaded appearance. Exterior white. Inte- rior white to pale-lemon, commonly with a rose tinge on the ends of the hinge or along the margins of the valves. Lunule just in front of the beaks is deep, heart-shaped, small and nearly all on the right valve. A common trop- ical species, Do not confuse with C. orbiculata. Codakia costata Orbigny Costate Lucina North Carolina to southeast Florida and the West Indies. % inch in length, variable in shape, but usually orbicular, quite obese, white to yellowish in color. With fine radial ribs, usually in pairs which are crossed by very fine concentric threads. Beaks also- with this sculpturing. Lunule small, indistinct, lanceolate, slightly more on the right valve. Com- pare its poorly defined lunule with those of orbicularis and orbiculata. Mod- erately common offshore on sandy bottoms. Subgenus Epilucina Dall 1901 Codakia californica Conrad Californian Lucina Plate 31¢ Crescent City, California, to Lower California. CHAMIDAE 391 1 to 1% inches in length, oval to circular, moderately inflated. Exterior dull-white with numerous, crowded, rather distinct, but small, concentric threads. Lunule of right valve like a small, depressed, lanceolate shield which fits snugly into a similarly shaped recess in the left valve. A common littoral species in southern California and down to 78 fathoms. Do not confuse with large specimens of Diplodonta. Subgenus Ctena Morch 1860 Codakia orbiculata Montagu Dwarf Tiger Lucina Plate 3o0l North Carolina to the south half of Florida and the West Indies. 1 inch or less in length, very similar to orbicularis, but with a large, elongate lunule in front of the beaks (instead of small and heart-shaped), and with stronger, less numerous, commonly divaricate ribs which are noticeable right up to the ends of the beaks. This species is much fatter and never has pink coloring inside. Common in sand from low water to 100 fathoms. The form filiata Dall has finer sculpturing much like orbicularis, is often yellowish in color, but can be readily distinguished from the latter by its elongate lunule. Common in the Gulf of Mexico. Genus Divaricella von Martens 1880 Divaricella quadrisulcata Orbigny Cross-hatched Lucina Plate 30m Massachusetts to south half of Florida and the West Indies. % to 1 inch in length, almost circular, moderately inflated, and glossy- white in color. Sculpture of fine, criss-cross or divaricate, impressed lines. Inner margin minutely impressed. A very common species washed ashore on sandy beaches. It is used extensively in the shellcraft business. D. dentata Wood from the West Indies is very similar, but its inner margin is smooth. Family CHAMIDAE a. Shell equivalve, with a distinct lunule; radial rows of spines 2. 2. _ Echinochama aa. Shell very inequivalve; ne fenuies b. Umbones turning from right to left; attached by left valve . Chama bb. Umbones turning from left to right; attached by the right valve. Sr fin 08 1k ee _ Pseudochama 392 American Seashells Genus Chama Linné 1758 Chama macerophylla Gmelin Leafy Jewel Box Plate 37b; figure 79b North Carolina to southeast Florida and the West Indies. This is the most common and most brightly hued Atlantic species. In quiet waters it may develop spine-like foliations to such an extent that it resembles the Spiny Oyster, Spondylus. Exterior variously colored: lemon- yellow, reddish brown, deep- to dull-purple, orange, white, or a combination of these colors. Inner edges of the valves have tiny, axial ridges or crenula- tions. The scale-like fronds have minute radial lines. Compare with sinuosa. Figure 79. Atlantic Chamas. Diagrammatic drawings of the deep valves, showing direction of growth and the juncture of the pallial line and muscle scars. a, Chama sinuosa Br oderip; b, Chama macerophylla Gmelin, ec, Pseudochama radians Lamarck. Chama congregata Conrad Little Corrugated Jewel Box Plate 37d North Carolina to Florida and the West Indies. Rarely over 1 inch in size. This species closely resembles the common macerophylla, but in place of numerous foliations there are low axial corru- gations or wavy cords. The unattached valve may have a few short, flat spines. There are fine crenulations on the inner margins of the valves. The color is usually dull with darker specklings. In rocky areas they live in crev- ices and under stones. Commonly found attached to pen and ark shells. Chama sinuosa Broderip White Smooth-edged Jewel Box Figure 79a South half of Florida and the West Indies. 1 to 3 inches in size. The color is always whitish, although the interior may be stained with dull-green. There are no crenulations on the inner edges CHAMIDAE 393 of the valves. The pallial line runs directly to the anterior muscle scar and not past the end as in the other species. This is a reef species. An ecological variety of heavy shell has been named firma Pilsbry and McGinty 1938. Chama pellucida Broderip Clear Jewel Box Plate 37a Oregon to Chile. 1% to 3 inches in size, with frond-like, smoothish foliations. Color opaque to translucent-white. Interior chalk-white, the margins minutely toothed or crenulate. Commonly found attached to pilings, breakwaters and floating wood. Also dredged down to 25 fathoms. Genus Pseudochama Odhner 1917 These are mirror images of the chamas. According to Odhner, the anat- omy and prodissoconchs differ in the two genera. Pseudochama radians Lamarck Atlantic Left-handed Jewel Box Plate 37c; figure 79c¢ Southern Florida and the West Indies. 1 to 3 inches in size. This is the only species of Psewdochama in eastern America. It is not very colorful, and ranges from a dull-white to a dull purplish red. The interior is commonly stained with mahogany-brown. Crenulations are present on the inner edges of the valves. In shape, it is a mirror image of simuosa. P. ferruginea Reeve is considered a synonym. Common. Pseudochama exogyra Conrad Pacific Left-handed Jewel Box Oregon to Panama. Similar to pellucida, but attached by the right valve which, when viewed from the inside, is arched counterclockwise. The opaque whitish area inside is generally not bordered by tiny crenulations. A common intertidal species. Pseudochama echinata Broderip in the Gulf of California is a popular shell which is characterized by a watermelon-red hinge and purple-stained interior. Pseudochama granti Strong (Grant’s Chama), dredged off central Cali- fornia and Catalina Island, is about 1 inch in size, with prickly spines on the underside of the attached, cup-formed valve. One end of the valve is tinted with rose inside and out. Not common. 394 American Seashells Genus Echinochama P. Fischer 1887 Echinochama cornuta Conrad Florida Spiny Jewel Box Plate 37g North Carolina to both sides of Florida to Texas. 1 to 1% inches in length, quadrate in outline and rather obese and heavy. Lunule distinct and broadly heart-shaped. With 7 to 9 rows of moderately long, stoutish spines, between which the shell is grossly pitted. Exterior creamy-white; interior white or flushed with bright pinkish mauve. Attached to a small pebble or broken shell by the right valve. Common from 3 to 40 fathoms, and commonly washed ashore. Echinochama arcinella Linné (True Spiny Jewel Box, pl. 37h) from the West Indies to Brazil has 16 to 35 (commonly 20) radial rows of slender spines. The shell is not as obese nor as heavy as cornuta. The subspecies californica Dall (pl. 37e) 1s very similar, with slightly longer spines and with a more compressed shell. It ranges from the Gulf of California to Panama in offshore water. Superfamily LEPTONACEA Family LEPTONIDAE A group of small, fragile, inflated, translucent clams which are parasitic or commensal on other marine creatures or are active crawlers like the gastro- pods. Most species brood their young inside the mantle cavity. The family is also named Erycinidae and Kelliidae. Genus Kellia Turton 1822 Shell unsculptured, inflated and oval-oblong. Lateral teeth present. 2 cardinal teeth in the right valve. Kellia laperoust Deshayes La Perouse’s Lepton Alaska to Panama. %4 to 1 inch in length, oval-oblong, rather obese and with small beaks near the center. Shell fairly strong, chalk-white, but commonly covered with a smooth, glossy, greenish to yellowish-brown periostracum which, however, is commonly worn away in the beak area. Very common. Found attached to wharf pilings among mussels and chama shells. Genus Lasaea Brown 1827 Shell very small, beaks nearer one end. Teeth the same as in Kellia. LEPTONIDAE 395 Lasaea cistula Keen Little Box Lepton Southern half of California to Peru. 44. of an inch in length (one of the smallest of our American clams), oval-oblong to quadrate, with one end slightly more rounded. Beaks slightly nearer the posterior end. Shell very obese to moderately inflated. Color light-tan with dark carmine around the dorsal margin area, and commonly blushed on the sides with light-carmine. Coarse, concentric growth lines, especially in the adults. Periostracum thin and yellowish tan. Found nestled together in great numbers attached to seaweed holdfasts and among mussels. Lasaea subviridis Dall (British Columbia and south) is much more com- pressed, smoother, with smaller beaks, but otherwise similar to cistula. Com- mon. Genus Pseudopythina P. Fischer 1884 Shell small and quadrangular. Lateral teeth absent; 1 cardinal tooth in each valve. Pseudopythina rugifera Carpenter Wrinkled Lepton Figure 80a Alaska to Lower California. ¥% to % inch in length, oval-oblong, moderately obese, fairly fragile, beaks close together and located about the middle of the shell. Shell white, but in live specimens covered with a thin, light-brown, semi-glossy periostra- cum which is feebly and concentrically wrinkled. The ventral edge of the valves is slightly indented in the middle in some specimens. May be found attached to crustaceans and the sea mouse, Aphrodita, or be free. Pseudopythina compressa Dall (Alaska to Mexico, the Compressed Lep- ton) is similar in size and outline, but is considerably compressed (thinner), smoothly polished in the beak area and with much less periostracum. Com- mon. Genus Mysella Angas 1877 Two cardinal teeth in the right valve, none in the left. Rochefortia Velain is this genus but a later name by several months. Mysella planulata Stimpson Atlantic Flat Lepton Nova Scotia to Texas and the West Indies. ¥ inch in length, oval-oblong in side view, well-compressed, and fairly 396 American Seashells fragile. Beaks small, % the distance back from the anterior end. Dorsal mar- gin of valves pushed in, both in front and back of the beaks. There is no thickening of the hinge line directly below the beaks. Color white, with a thin, nut-brown, smoothish periostracum. Moderately common attached to buoys, eel-grass and wharf pilings. EON, WN bp Me LP 4) {ls Figure 80. Pacific Lepton Clams. a, Psewdopythina rugifera Cpr., 2 inch, at- tached to the underside of a crawfish, b, Mysella tumida Cpr., 4 inch, ¢, animal of the clam, Bornia longipes Stimpson, 4% inch (Carolinas). Mysella golischi Dall Golisch’s Lepton Southern third of California. % inch in length, oval-oblong in side view, moderately compressed and rather fragile. Beaks small, 94 the distance back from the anterior end. The dorsal margin of the valve is pushed in slightly just anterior to the beak. Shell white, semi-transparent, with its glossy exterior having irregular, con- centric wrinkles. In live specimens, there is a thin yellowish brown periostra- cum. These clams are found attached to the gills or legs of the large sand crab, Blepharopoda occidentalis, Common, M. pedroana Dall, known from CARDIIDAE 397 a single specimen, is much more oblique in shape, resembling the equally rare Erycina fernandina Dall from off Florida. Mysella tumida Carpenter Fat Pacific Lepton Figure 80b Alaska to Lower California. % to %6 of an inch in length, moderately compressed, somewhat tri- angular in shape. The tiny beaks are almost at the very posterior end. Shell dull-white, but commonly covered with a light-brown, smoothish periostra- cum which is faintly marked with concentric, microscopic wrinkles. The hinge teeth are large in comparison to those in other species. Common from low water to 99 fathoms. Has been found in duck stomachs, Superfamily CARDIACEA Family CARDIIDAE Subfamily TRACHYCARDIINAE Genus Trachycardium Morch 1853 Trachycardium muricatum Linné Yellow Cockle Plate 39p North Carolina to Florida, Texas and the West Indies. 2 inches in height, subcircular, with 30 to 40 moderately scaled, radiating ribs. Externally light-cream with irregular patches of brownish red or shades of yellow. Interior commonly white, rarely yellow-tinted especially in Flor- ida. A very common, shallow-water species. Compare with egmontianum and magnum which are both more elongate. Trachycardium egmontianum Shuttleworth Prickly Cockle Plate 39-0 North Carolina to south Florida and the West Indies. 2 inches in height, with 27 to 31 strong, prickly, radial ribs. Externally whitish to tawny-gray with odd patches of weak yellow, brown or dull- purple. Interior glossy, commonly brightly hued with salmon, reddish and purple. Do not confuse with muricatum which is more oval, has more ribs which are not sharply scaled at the center of the shell and is commonly only yellowish inside. A common shallow-water species, especially on the Gulf side of Florida. Trachycardium isocardia Linné from the West Indies has larger and slightly different scales, 32 to 37 ribs and has not been recorded from Florida. Trachycardium magnum Linneé Magnum Cockle Lower Florida Keys and the West Indies. 398 American Seashells 2 to 3% inches in height, elongate, with 32 to 35 mostly smooth ribs. The ribs at the posterior end have small, tooth-like scales. Middle ribs com- pletely smooth and squarish. Externally light-cream with irregular patches of reddish brown. Interior china-white with the deepest part flushed with orange-buff. As a rule, the posterior margin is pale-yellow, merging into pale-purple at the extreme edge. A West Indian species which has been found on the most southerly keys, Trachycardium quadragenarium Conrad Giant Pacific Cockle Plate 31a Santa Barbara to Lower California. 3 to 6 inches in size, commonly slightly higher than long, inflated, and with 41 to 44 strong, closely set, squarish, radial ribs which bear small, up- right, strong, triangular spines, especially at the anterior, posterior and ventral portions of the shell. Ribs on beaks smoothish. Exterior whitish tan, but commonly covered with a thin, opaque-brown periostracum. Interior dull- white. Moderately common from shore to 75 fathoms. Known locally as the Spiny Cockle. Genus Papyridea Swainson 1840 Papyridea soleniformis Bruguicre Spiny Paper Cockle Plate 39n North Carolina to south half of Florida and the West Indies. 1 to 1% inches in length, fairly fragile, moderately compressed, and gaping posteriorly where the margin of the valve is strongly denticulated by the ends of the dozen radial, finely spinose ribs. Exterior tawny with rose flecks or mottlings. Interior glossy, mottled with violet and white, rarely a solid pastel-orange. Moderately common from low tide to several fathoms. The name hiatus Meuschen used for this species in Jobnsonia is not valid (ruled non-binomial). A similar species, P. semisulcata Sowerby (Frilled Paper Cockle, pl. 32c) found from low water to 40 fathoms from southern Florida to the West Indies, is less than % inch in length, white, twice as fat, and with longer denticulations at the end of the 12 to 15 radial ribs. Uncommon, except off Miami where it 1s commonly dredged. Subfamily FRAGINAE Genus Trigoniocardia Dall 1900 Trigoniocardia media Linné Atlantic Strawberry Cockle Plate 39m North Carolina to southeast Florida and the West Indies. CARDIIDAE 399 1 to 2 inches in size, squarish in outline, thick, inflated, with 33 to 36 strong radial ribs which are covered with close-set, chevron-shaped plates. External color whitish with mottlings of reddish brown. Interior usually white, or may be flushed with orange, rose-brown or purple. The posterior slope is pushed in somewhat and is slightly concave. A relatively common species found in shallow to moderately deep water. The Western Strawberry Cockle, T. biangulata Sowerby, is the Cali- fornian counterpart of the above species. It is 1% inches in length, with about 30 strong ribs; exterior yellowish white, interior reddish purple. Moderately common, Subfamily PROTOCARDIINAE Genus Nemocardium Meek 1876 Nemocardium centifilosum Carpenter Hundred-lined Cockle Alaska to Lower California. % to % inch in length, almost circular; posterior third of shell with cancellate sculpturing and separated from the finely ribbed anterior two thirds of the shell by a single raised rib. Edge minutely serrate. Exterior with gray, greenish gray or brownish gray, thin, fuzzy periostracum. In- terior dull-white. Fairly common. Genus Microcardium Thiele 1934 Microcardium peramabile Dall Eastern Micro-cockle Rhode Island to southeast Florida and the West Indies. % to % inch in length, thin, inflated, subquadrate, white, but may be mottled tan on the anterior slope. Sculpture prominent on the posterior third of the valve. It consists of about go closely packed, radial ribs (spinose posteriorly) which are crossed by minute concentric threads. The anterior two thirds is separated from the rest of the shell by a single, crested, spinose, radial rib. Very commonly dredged off eastern Florida. Microcardium tinctum Dall, found with the above species, is 34 inch in length, stained with rose-red and has more than 150 minute, radial ribs. Uncommon, Subfamily LAEVICARDIINAE Genus Laevicardium Swainson 1840 Laevicardium laevigatum Linné Common Egg Cockle Plate 39k North Carolina to both sides of Florida and the West Indies. 400 American Seashells 1 to 2 inches in size, higher than long, polished smooth, inflated, fairly thin and obscurely ribbed. Exterior generally whitish, but may be rose-tinted, mottled with brown or flushed with purple, yellow or burnt-orange. Interior similarly colored. With about 60 very fine, subdued radial ribs. A common shallow-water species. The name serratum Linné has been erroneously ap- plied to our Atlantic species by some workers. Laevicardium mortoni Conrad Morton’s Egg Cockle Plate 39] Cape Cod, Massachusetts, to Florida and the Gulf of Mexico. %4 to 1 inch in size, ovate, glossy, similar to Jaevigatum, but commonly with brown, zigzag markings and with fine, concentric ridges which are minutely pimpled. Common in southern New England from shallow water to 2 fathoms. A food of wild ducks. Laevicardium pictum Ravenel Ravenel’s Egg Cockle South Carolina to southeast Florida and the West Indies. % to 1 inch in height, obliquely triangular in shape, polished and only moderately inflated. Exterior white or cream with delicate shades or rose or brown and with a weak, iridescent sheen. A color form has strong, brown, zigzag streaks. Beaks very low and near the anterior end. Very faint radial and concentric lines present. Dredged from 75 to 85 fathoms. An uncommon and attractive species. Laevicardium sybariticum Dall 1886 (Dall’s Egg Cockle, rare, same range), is more inflated, squarish in shape and with deep-pink breaks. Laevicardium substriatum Conrad Common Pacific Egg Cockle Ventura County, California, to the Gulf of California. Less than 1 inch in size, obliquely ovate, smooth and slightly compressed. Color tan with closely set, narrow, radial bands of reddish brown. These lines are commonly interrupted. Interior cream with cobwebby mottlings of purplish brown. Very common in such localities as Mission Bay and New- port. Laevicardium elatum Sowerby Giant Pacific Egg Cockle San Pedro, California, to Panama. 3 to 7 inches in height, oval, inflated, slightly oblique, with numerous, shallow, radial grooves, but the posterior and anterior regions are smooth. CARDIIDAE 401 Exterior orange-yellow, interior china-white. This is the largest species of recent cockles and is moderately common. Genus Dinocardium Dall 1900 Dinocardium robustum Solander Giant Atlantic Cockle Plate 32a Virginia to north Florida, Texas and Mexico. 3 to 4 inches in size, ovate, inflated, with 32 to 36 rounded, radial, smoothish ribs. Externally straw-yellow with its posterior slope mahogany- red shading toward purple near the edge. Interior rose, with brownish posteriorly and with a white anterior margin. This is the large, common cockle washed ashore along the Carolina and Georgia strands. It is not found in southwest Florida. When the Florida Canal project was begun in 1935, President F. D. Roosevelt was presented with a large silver platter on which was set a specimen of Dinocardium, encased in gold and containing a portion of the first earth excavated as a result of the blast set off by the President. The canal was never completed. Dinocardium robustum vanhyningi Clench and L. C. Smith Vanhyning’s Cockle Plate 32b Tampa Bay to Cape Sable, Florida. 3% to 5 inches in size, higher than long, with 32 to 36, smoothish, rounded, radial ribs. Externally straw-yellow with irregular patches and bands of mahogany-red to purplish brown. It is more elongate, glossier and more colorful than robustum, and is the common, large cockle on the west coast of Florida. They are popular souvenirs, being used for ash trays, melted-butter dishes, baking dishes and for holding pincushions. Genus Serripes Gould 1841 There is only one species of this peculiar genus of cockles in North American waters. The hinge is narrow, the cardinal teeth weak, and the ligament is large. The radial ribs are very weak. Serripes groenlandicus Bruguiere Greenland Cockle Plate 32d Arctic Seas to Cape Cod, Massachusetts. Alaska to Puget Sound, Wash- ington. 2 to 4 inches in length, moderately thin but strong, inflated, almost Zs Wrnro me ° PLATE 33 LARGE SCALLOPS Tryon’s ScaLtop, Aequipecten glyptus Verrill, 2% inches (Massachusetts to the Gulf of Mexico), p. 366. Lion’s Paw, Lyropecten nodosus L., 5 inches (North Carolina to the West Indies), p. 366. ATLANTIC DEEPSEA SCALLop, Placopecten magellanicus Gmelin, 8 inches (Lab- rador to off North Carolina), p. 366. ZiczaG ScatLop, Pecten ziczac L., 3 inches (North Carolina to the West Indies), p. 362. San Dirco Scatiop, Pecten diegensis Dall, 3 inches (California), p. 36r. LAvurRENTIAN ScaLLop, Pecten laurenti Gmelin, 3 inches (West Indies), p. 362. RAVENEL’s ScCALLoP, Pecten raveneli Dall, 11% inches (North Carolina to Texas and the West Indies), p. 362. Circurar Paciric Scattop, Aequipecten circularis Sby., 2% inches (Pacific side of Central America), not in text. Atiantic Bay Scatiop, Aequipecten irradians irradians Lam., 3 inches (At- lantic Coast), p. 367. Carico ScaLiop, Aequipecten gibbus L., 1% inches (North Carolina to West Indies), p. 368. bs: d. PLATE 34 SMALL SCALLOPS SENTIS SCALLOP, Chlamys sentis Reeve, 1 inch (North Carolina to the West Indies), p. 363. OrNATE SCALLOP, Chlamys ornata Lam., 1 inch (Southeastern Florida and West Indies), p. 363. Mixprep’s ScaLLop, Chlamys mildredae F. M. Bayer, | inch. Holotype (Florida and Bermuda), p. 363. and e. RoucH ScaLLop, Aequipecten muscosus Wood, e. is a large, worn specimen. | inch (Southeastern United States and the West Indies), p. 307. LitrLeE Knopsy Scatiop, Chlamys imbricata Gmelin, 1 inch (South- eastern Florida and the West Indies), p. 364. ANTILLEAN SCALLOP, Lyropecten antillarum Recluz, 14 inch (South- eastern Florida and the West Indies), p. 366. Nuc.Leus ScALLop, Aequipecten nucleus Born, 1 inch (Southeastern Florida and the West Indies), p. 368. KELP-WEED SCALLOP, Leptopecten latiauratus Conrad, 1 inch (Califor- nia), p. 365. PaciFic SPEAR ScALLop, Chlamys hastata hastata Sby., 2 inches (Cali- fornia), p. 364. PaciFic Pink ScaLLop, Chlamys hastata hericia Gould, 2 inches (Alaska to San Diego, California), p. 364. Hinp’s Scattop, Chlamys hindsi Dall, 2 inches (Alaska to San Diego, California), p. 365. b. d. mn. n. PLATE 35 PEARL OYSTERS AND MUSSELS LisTErR’s TREE Oyster, Isognomon radiatus Anton, 114 inches (South- eastern Florida and the West Indies), p. 358. Frat TREE Oyster, Jsognomon alatus Gmelin, 214 inches (Florida and West Indies), p. 358. ATLANTIC PEARL OysTerR, Pinctada radiata Leach, 2 inches (Florida and West Indies), p. 359. ATLANTIC WING OysTER, Pteria colymbus Roding, 2 inches (North Carolina to West Indies), p. 359. Kitren’s Paw, Plicatula gibbosa Lam., 1 inch (North Carolina to Gulf States and south), p. 361. Roucu Lima, Lima scabra Born, 2 inches (Southeastern Florida and the West Indies), p. 370. Spiny Lima, Lima lima L., 14% inches (Southeastern Florida and the West Indies), p. 370. RoucH Lima, Lima scabra Born, smooth form tenera Sby., 2 inches (Southeastern Florida and West Indies), p. 371. YeLLow Mussex, Brachidontes citrinus Roding, | inch (Florida and Wrest Indies); p. 332. ScorcHED MussEL, Brachidontes exustus L., 44 inch (North Carolina to the Wiest Indies);sps 392: ComMMOoN JINGLE SHELL, Anomia simplex Orbigny, 1 inch (Atlantic Goast) pa oi2. Turre Musser, Modiolus americanus Leach, 3 inches (North Carolina to the West Indies), p. 351. Biur MusseEt, Mytilus edulis L., 24% inches (Arctic to South Carolina), OE ie Hookxep Mussei, Brachidontes recurvus Raf., 2 inches (Cape Cod to West Indies), p. 353. Living Lima Cxiam, Lima scabra Born, showing the delicate tentacles along the mantle edge which aid this clam in swimming (South- eastern Florida and West Indies), p. 370. PLATE 36 THORNY OYSTERS Paciric Tuorny Oyster, Spondylus pictorum Schreiber, 5 inches (Gulf of California to Panama), p. 370. b. ArLantic THorny OysTErR, Spondylus americanus Hermann, 3 to 4 snches. Comes in many colors. Specimen from the Leo Burry collection. (Florida and the West Indies), p. 369. a. ge he PLATE 37 JEWEL BOXES CLEAR JEWEL Box, Chama pellucida Brod., 2 inches (Oregon to Chili), job Sekt Leary JEWEL Box, Chama macerophylla Gmelin, 2'4 inches (North Carolina to the West Indies), p. 392. ATLANTIC LEFT-HANDED JEWEL Box, Pseudochama radians Lam., 3 inches (Southern Florida and the West Indies), p. 393. LiTTLE CorRUGATED JEWEL Box, Chama congregata Conrad, 1 inch (North Carolina to the West Indies), p. 392. CALIFORNIA SPINY JEWEL Box, Echinochama arcinella californica Dall, Holotype. 2 inches (off, Lower California to Panama), p. 394. CHERRY JEWEL Box, Chama florida Lam., 1 inch (West Indies), not 1n text. FLoriwa Spiny JEWEL Box, Echinochama cornuta Conrad, | inch (North Carolina to ‘Texas), p. 394. TRUE Spiny JEWEL Box, Echinochama arcinella L., 14% inches (West Indies to Brazil), p. 394. mn. O. PLATE 38 ATLANTIC OYSTERS, LUCINAS AND VENUS CLAMS HonEYCOMBED OysTER, Pycnodonta hyotis L., 24% inches (Florida and West Indies), p. 374. ATLANTIC FALSE JINGLE SHELL, Pododesmus rudis Broderip, 2 inches (North Carolina, south), p. 372. Coon OysTErR, Ostrea frons L., 2 inches a, b and c are from a sunken wreck off Miami. Gift of Ethel Townsend (Florida, south), p. 373. Ticer Lucina, Codakia orbicularis L., 3 inches (Gulf coast and West Indies), p. 390. CuaALky Burrercur, Anodontia philippiana Reeve, 3 inches (North Carolina to Cuba), p. 389. Burrercur Lucrna, Anodontia alba Link, 2 inches (North Carolina to ‘Texas and West Indies), p. 389. Turck Lucina, Phacoides pectinatus Gmelin, 2 inches (North Carolina to ‘Texas and West Indies), p. 388. PENNSYLVANIA Lucina, Lucina pennsylvanica L., 114% inches (North Carolina to West Indies), p. 385. FLoripaA Lucina, Lucina floridana Conrad, 114 inches (Western Florida to Pexas), p. 337: Norvtueast Lucina, Phacoides filosus Stimpson, 2 inches (off entire east coast), p. 389. AmeEtHyst Gem CLAM, Gemma gemma Totten, 14 inch (east coast; for details see figure 84), p. 418. Empress VeENus, Antigona strigillina Dall, 14% inches (Southeastern Florida, south), p. 404. QUEEN VENus, Antigona rugatina Heilprin, 1 inch (North Carolina to West Indies), p. 405. HEART-SHAPED VENUS, Pitar cordata Schwengel, 114 inches (Gulf of Mexico, offshore), p. 414. Disk Dosinra, Dosinia discus Reeve, 3 inches (Virginia to Gulf of Mexico and Bahamas), p. 417. b. d. m. n. PLATE 39 VENUS CLAMS AND COCKLES Kinc VENus, Chione paphia L., 114 inches (Florida Keys and West Indies), p. 409. SunrAyY Venus, Macrocallista| nimbosa Solander, 5 inches (North Carolina to the Gulf States), p. 416. IMPERIAL Venus, Chione latilirata Conrad, | inch (North Carolina to the Gulf States), p. 409. Licutinc Venus, Pitar fulminata Menke, | inch (North Carolina to the West Indies) ) p. 414. Carico CiaM, Macrocallista maculata L., 2 inches (North Carolina to the West Indies), p. 416. Roya Comes Venus, Pitar dione L., 114 inches (Texas to the Caribbean), JO Sell oy Lapy-1n-WaitinG VENUS, Chione intapurpurea Conrad, 114 inches (North Carolina to the Gulf and West Indies), p. 407. CROSS-BARRED VENUS, Chione cancellata L., 1 inch (North Carolina to the West Indies), p. 407. GLOoRY-OF-THE-SEAS VENUS, Callista eucymata Dall, 114 inches (North Carolina to the West Indies), p. 415. PornreD VENus, Anomalocardia cuneimeris Conrad, 34 inch (Florida to exas)iy ps2 09: Common EGG Cockie, Laevicardium laevigatum Linné, 2 inches (North Carolina to the West Indies), p. 399. Morron’s Ecc Cockie, Laevicardium mortoni Conrad, | inch (Massa- chusettsito Wexas);, p. 4.00: ATLANTIC STRAWBERRY COCKLE, Trigoniocardia media L., 114 inches (North Carolina to the West Indies), p. 398. Siny Paper Cockie, Papyridea soleniformis Brug., 1 inch (North Carolina to the West Indies), p. 398. Prickty Cockie, Trachycardium egmontianum Shuttleworth, 2 inches (North Carolina to Cuba), p. 397. YELLOW CockiE, Trachycardium muricatum L., 2 inches (North Caro- lina to the Gulf States and West Indies), p. 397. 7. PLATE 40 SEMELES AND TELLINS Gaupy Asapuis, Asaphis deflorata L.., 2 inches (Southeastern Florida and West Indies), p. 439. PurPLisH SEMELE, Semele purpurascens Gmelin, | inch (North Caro- lina to West Indies), p. 435. LarGE StTrIGILLA, Strigilla carnaria L., 44 inch (North Carolina to West Indies), p. 428. ATLaAntTic Sancuin, Sanguinolaria cruenta Solander, 1% inches (Florida, the Gulf and West Indies), p. 439. SunrisE TEN, Tellina radiata L., 3 inches (South Carolina to the West Indies)» pre2 W. and g. WuiTrE ATLANTIC SEMELE, Semele proficua Pulteney, | inch. f is the rayed form, radiata Say (North Carolina to the West Indies), oh geike RosE Perat TeLuin, Tellina lineata Turton, 114 inches (Florida and the West Indies), p. 427. GreEAT TELLIN, Tellina magna Spengler, 4 inches (North Carolina to tie Wiest Indies); p. 427. Faust TELuin, Arcopagia fausta Pulteney, 3 inches (North Carolina to the West Indies), p. 428. SmMooTH ‘TELLIN, Tellina laevigata L., 3 inches (Florida and the West indies) py 427. SPECKLED ‘TELLIN, Tellina interrupta Wood, 3 inches (North Carolina to the West Indies), p. 422. Canby Stick ‘TELLIN, Tellina similis Sby., 1 inch (Florida and the West Indies), p. 426. ALTERNATE ‘TELLIN, Tellina alternata Say, 244 inches (North Carolina to the Gulf States), p. 427. CARDUDAE 403 round and slightly gaping at the posterior end. Exterior brownish gray and may be with brown, concentric rings of growth. Interior dull-white. Beaks inflated and high. Ligament large and strong. No lunule or escutcheon. Weak radial ribs seen at both ends only. Concentric growth ridges promi- nent near the margins. Muscle scars and pallial line deeply impressed. Foot of animal large and suffused with heavy, red mottlings. Very commonly dredged in cold, northern waters. Genus Clinocardium Keen 1936 Clinocardium ciliatum Fabricius Iceland Cockle Plate 32e Greenland to Massachusetts. Alaska to Puget Sound, Washington. 1% to 3 inches in size, a little longer than high, with 32 to 38 ridged radial ribs which are crossed by coarse concentric lines of growth. Exter- nally drab grayish yellow with weak, narrow, concentric bands of darker color. Interior ivory. Periostracum gray and conspicuous. Especially abun- dant from Maine northward in offshore waters. Clinocardium nuttalli Conrad Nuttall’s Cockle Plate 31b Bering Sea to San Diego, California. 2 to 6 inches in length; smaller ones being almost round, adults tending to be higher than long; moderately compressed; commonly with 33 to 37 coarse radial ribs which are creased by half-moon-shaped riblets. Older specimens worn smoothish. Exterior drab-gray, with a brownish yellow, thin periostracum. Common offshore. Once called C. corbis Martyn. Known locally as the Basket Cockle. Clinocardium fucanum Dall Fucan Cockle Sitka, Alaska, to off Monterey, California. 1 to 1% inches in length, longer than high, moderately inflated, and with 45 to 50 low, poorly developed, radial ribs which are crossed by mi- croscopic concentric lines. No wavy, radial furrow on the upper posterior edge of the shell. Color whitish with a grayish-brown periostracum. Com- mon in the Puget Sound area. Young C. nuttalli are distinguished from this species by their 2 first ribs behind the ligament which are large, rounded and make a wavy edge to the shell. In small specimens of C. ciliatum, the top edges of the ribs are sharp; in fucanum they are rounded. 404 American Seashells Genus Cerastoderma Poli 1795 Cerastoderma pinnulatum Conrad Northern Dwarf Cockle Plate 30c Labrador to off North Carolina. ’4 to % inch in length, thin, with 22 to 28 wide, flat ribs which have delicate, arched scales on the anterior slope of the shell. Scales missing on the central portion of the valve. Externally cream, interior glossy and white, rarely tinted with orange-brown. Commonly dredged from 7 to 100 fathoms. Superfamily VENERACEA Family VENERIDAE The classification of the family of Venus clams has been one of continual debate and rearranging for some years. Our presentation here is no better than has been suggested before, but at least it is in a form which is conserva- tive and most likely to be accepted by the majority. Rather than accept a separate family Chionidae or consider it a subfamily remotely related to the Venerinae, we have allied it as an artificial group in the subfamily Venerinae. I suspect that an anatomical study of the soft parts will support this course. Subfamily VENERINAE Sculpture usually both radial and concentric; anterior lateral present, especially in the left valve, but often extraordinarily vestigial. Genus Antigona Schumacher 1817 Subgenus Dosina Gray 1835 Antigona listeri Gray Princess Venus Plate 32m Southeast Florida and the West Indies. 2 to 4 inches in length, oblong-oval, obese. Resembling Mercenaria campechiensis, but characterized by numerous, fine, radial riblets which cause the sharp, concentric ribs to be serrated or beaded. Each side of the lunule is bounded by a long, deep, narrow furrow. Posterior muscle scar usually stained brown. Moderately common in shallow water in sand. Subgenus Circomphalus Morch 1853 Antigona strigillina Dall Empress Venus Plate 381; figure 81d Southeast Florida and the West Indies. VENERIDAE 405 1% inches in length, externally very much like a small Mercenaria campechiensis, but not as elongate and with more distinct, concentric riblets. Internally, it is distinguished easily by the extremely small, if not absent, pallial sinus, by the very thick margin of the shell, and in the left valve by the presence of a button-like anterior lateral “tooth.” Exterior whitish. Dredged occasionally from 40 to 70 fathoms. Considered a collector’s item. Figure 81. Some venerid clams. a and b, Compsomyax subdiaphana Cpr., 2 inches (Pacific Coast); ec, Dosinia discus Reeve, 2 inches (Atlantic Coast); d, Antigona strigillina Dall, 14% inches (Florida and West Indies); e, left valve of Pitar morrhuana Linsley, 1% inches (Atlantic Coast). Antigona rugatina Heilprin Queen Venus Plates 38m; 32n North Carolina to southeast Florida and the West Indies. 1 to 1% inches in length, rather circular, inflated, and characterized by strong, raised, lamellate, concentric ribs between which are 5 or 6 smaller, raised concentric ridges. Lunule heart-shaped, well-impressed, bordered by a fine, deep line, and crossed by numerous raised threads. Escutcheon well- formed, smoothish. Color cream to whitish with light-mauve mottlings. Very uncommon. Antigona rigida Dillwyn from the West Indies is very similar, but not nearly so obese, and its concentric ridges are stronger and smoother. “Chionid” Group Ovate-trigonal, inequilateral, sculpture usually cancellate; lunule im- pressed. Inner margins usually crenulate. Teeth strong, without the tiny, pimple-like anterior lateral. Pallial sinus short. This section or group is 406 American Seashells considered by some to be of family or subfamily rank. See Frizzell and Myra Keen. Genus Mercenaria Schumacher 1817 The Hard-shell Clams or Quahogs belong to this genus. The shell is large and thick; lunule large, heart-shaped and bounded by an incised line. Inner margin crenulate. 3 cardinals in each valve. Left middle cardinal split. Formerly placed in the genus Venus many years ago, but almost universally placed in a genus by itself by modern workers. Mercenaria mercenaria Linné Northern Quahog Plate 32h Gulf of St. Lawrence to Florida and the Gulf of Mexico. Introduced to Humboldt Bay, California. 3 to 5 inches in length, ovate-trigonal, about % as high, heavy and quite thick. Moderately inflated. Sculpture of numerous, concentric lines of growth or small riblets. Near the beaks these lines are prominent and dis- tantly spaced. The exterior center of the valves has a characteristic smoothish or glossy area. Exterior dirty-gray to whitish; interior white, commonly with purple stainings. The entire lunule is *4 as wide as long. The form notata Say from the same region is externally marked with brown, zigzag mottlings. This species is very common and is used commercially for chowders and as clams-on-the-half-shell or “cherrystones.” Also known as the Hard-shelled Clam. Do not confuse with M. campechiensis. Mercenaria mercenaria texana Dall is a subspecies from the northern Gulf of Mexico region. It is characterized by a glossy central area on the outside of the shell, but has large, irregular, coalescing, flat-topped, con- centric ribs. Mercenaria campechiensis Gmelin Southern Quahog Plate 32g Chesapeake Bay to Florida, Texas and Cuba. 3 to 6 inches in length, very similar to mercenaria, but much more obese, a heavier shell, lacks the smooth central area on the outside of the valves, and the entire lunule is usually as wide as long. Always white internally. Rarely it has a purplish stain on the escutcheon and brown mottlings on the side. There have been a number of forms described. In the vicinity of St. Petersburg, Florida, there is a malformed race in which there is a sharp, elevated ridge passing from the umbo obliquely backward toward the pallial sinus on the inside of each valve. The Southern Quahog is common but has not been exploited commercially to any great extent. VENERIDAE 407 Genus Chione Miuhlfeld 1811 Shells trigonal or ovate; thick; 3 cardinal teeth in each valve; no anterior laterals; pallial sinus small and triangular; inner margins crenulated; lunule bounded by an indented line; escutcheon smooth and bounded by a small ridge. Subgenus Chione s. str. Chione cancellata Linné Cross-barred Venus Plate 39h North Carolina to Florida, Texas and the West Indies. 1 to 134 inches in length, varying from ovate to subtriangular in shape, thick; with strong, raised, curved, leaf-like, concentric ribs and numerous coarse radial ribs. Escutcheon long, smooth and V-shaped, commonly with 6 to 7 brown, zebra-stripes. Lunule heart-shaped, with minute vertical threads. Color externally is white to gray; internally glossy-white with a suffusion of purplish blue. A very common, shallow-water species in Florida. Beachworn specimens have a cancellate sculpturing. The subspecies mazycki Dall, off the Carolinas, Georgia and northeast Florida has a beautiful rosy interior. Chione intapurpurea Conrad Lady-in-waiting Venus Plate 39g North Carolina, the Gulf States to the West Indies. 1 to 1% inches both ways, thick, glossy-white to cream, interior white, commonly with a violet, radial band or splotch at the posterior third. Ex- terior with crowded, smooth, low, rounded, concentric ribs. The lower edge of these ribs bears many small bars which are lined up one below the other to give the shell the impression that it has axial ribs. The concentric ribs become sharp and higher at the shell’s extreme ends. Lunule with raised lamellations; escutcheon with very fine, transverse lines. Uncommon. Incorrectly spelled interpurpurea. Chione californiensis Broderip Common Californian Venus Plate 31} . San Pedro to northern South America. 2 to 2% inches high, a little longer, subtrigonal, moderately compressed, with sharp, raised, concentric ribs whose edges turn upwards, and with low, rather wide, rounded, radial riblets. Lunule heart-shaped and striated; es- cutcheon V-shaped in cross-section, long and smooth. The dorsal posterior end of the right valve is not as smooth and overlaps the left valve. Exterior 408 American Seashells creamy-white with faint mauve stripes on the escutcheon. Interior white, commonly with a purple splotch at the posterior end. This is a common shore species, formerly called C. succincta Val. Chione californiensis undatella Sowerby Frilled Californian Venus Plate 311 San Pedro, California, to northern South America. Differing from californiensis in being more inflated, usually with more numerous and more closely spaced, thinner concentric ribs, and retaining mauve-brown color splotches in the adults. Very common. Many workers consider this a full species, and apparently additional field study is necessary. Chione fluctifraga Sowerby Smooth Pacific Venus Plate 31k San Pedro, California, to the Gulf of California. 2% inches in height, slightly longer, moderately compressed, subtrigonal, radial grooves or ribs strong at the posterior third and at the anterior quarter of the shell; central area with stronger, low, rather wide, concentric ribs which may have coarse, half-moon-shaped beads. Lunule not well-defined; escutch- eon not well seen and not sunken nor smooth as in californiensis. Exterior creamy-white, semi-glossy, rarely stained with blue-gray. Interior white with purple splotches near the muscle scars or on the teeth. Not uncommon along the sandy shores in southern localities. Section Timoclea Brown 1827 Chione grus Holmes Gray Pygmy Venus Plate 321 North Carolina to Key West to Louisiana. % to %s inch in length, oblong, with 30 to 4o fine, radial ribs which are crossed by very fine, concentric threads. The posterior dozen ribs are cut along their length by a very fine groove. Dorsal margin of right valve fim- briated and overlapping the left valve. Lunule narrow, heart-shaped, colored brown. Escutcheon very narrow and sunken. Exterior colored a dull-gray, but some Florida ere tend to be whitish, pinkish or even orange. In- terior glossy-white with purplish brown area at the posterior end. Purple color on hinge at both ends. Commonly dredged in shallow water. Chione pygmaea Lamarck White Pygmy Venus Southeast Florida and the West Indies. VENERIDAE 409 Y% to % inch in length, similar to grus, but with prominent scales, 4 to 5 brown, zebra stripes on the escutcheon, with a white lunule, and the teeth purple only on the posterior half of the hinge. Beaks commonly pink. In- terior all white. Fairly common in shallow water. Subgenus Lirophora Conrad 1863 Chione paphia Linné King Venus Plate 39a Lower Florida Keys and the West Indies. 1¥% inches in length, similar to /atizrata, but not so heavy, with ro to 12 smaller, concentric ribs which are thin at their ends. From a side view, the dorsal margin of the lunule is very concave. Not very common in the United States. Chione latilirata Conrad Imperial Venus Plate 39c North Carolina to Florida and to Texas. 1 inch in length, very thick and solid, with 5 to 7 large, bulbous, con- centric ribs, usually rounded, but may also be sharply shelved on top. The ribs are not thin and flattened at their ends. Lunule heart-shaped, and, from a side view, its dorsal margin is almost straight. Surface of shell glossy, cream with rose and brown mottlings. Rather uncommon offshore in about 20 fathoms. Genus Anomalocardia Schumacher 1817 Anomualocardia cuneimeris Conrad Pointed Venus Plate 39} South half of Florida to Texas. ¥% to % inch in length, about %4 to % as high, pointed into a sharp, wedge-like rostrum at the posterior end. Lunule oval to slightly heart-shaped and faintly impressed. Wide, shallow escutcheon bordered by a weak ridge. Beaks tiny and inrolled. Sculpture of small, but distinct, rounded, concentric ribs which are more prominent near the beaks. Color variable: glossy-cream, white or tan with brown or purple rays of fine specklings. Interior white, purple or brown. Brackish water specimens are dwarfed. A common sandy shore species. A. brasiliana Gmelin (West Indian Pointed Venus) which is twice as large, less elongate, and with the concentric ribs extending over into the escutcheon area, has been erroneously reported from the United States. Common in the West Indies and south to Brazil. 410 American Seashells Genus Protothaca Dall 1902 Protothaca tenerrima Carpenter Thin-shelled Littleneck Vancouver, B.C., to Lower California. About 4 inches in length and 2% inches high, very compressed, relatively thin, with a chalky texture, with a few raised concentric lines and numer- ous very small radial threads. Lunule fairly defined. Exterior light gray- brown. Interior chalky-white. A fairly common species, commonly washed ashore on Californian beaches. Protothaca staminea Conrad Common Pacific Littleneck Plate 31m, n Aleutian Islands to Lower California. 1% to 2 inches in length, subovate, beaks nearer the anterior end; sculp- ture of concentric and radial ribs which form beads as they cross each other at the anterior end of the shell. Radial ribs stronger on the middle of the valves. Beaks almost smooth. Exterior rusty-brown with a purplish cast. A very abundant, wide-spread species with a number of varieties. Sometimes with a mottled color pattern. Variety or form: Jacimiata Carpenter reaches 3 inches in length, is coarsely cancellate and beaded, its color rusty-brown to grayish. Variety or form: ruderata Deshayes (typically a northern form) is chalky-white to gray, with concentric ribs large and coarse, commonly lamellate (see pl. 31-0). Compare with Tapes philippinarum, the Japanese Littleneck. Genus Humilaria Grant and Gale 1931 Hlumilaria kennerleyi Reeve Kennerley’s Venus Alaska to Carmel Bay, California. 2% to 4 inches in length, ovate-oblong, with the beaks near the anterior end. With sharp, concentric ribs whose “edges are bent upwards. Spaces between ribs. Color and texture like gray Portland cement. Interior white. Margin of shell finely crenulate, a feature that will distinguish it from worn specimens of Saxidomus. Dredged on mud bottoms from 3 to 20 fathoms. A collector’s item, although reasonably common. Genus Tapes Mihlfeld 1811 Subgenus Ruditapes Chiamenti 1900 Tapes philippinarum Adams and Reeve Japanese Littleneck Pueet Sound southward. VENERIDAE 411 1% to 2 inches in length, extremely close to Protothaca staminea and grata Sowerby (the latter’s range is from the Gulf of California to Panama), but differing from both in being much more elongate and more compressed. Its lunule and small escutcheon are more distinct and quite smooth as com- pared to those of staminea. The hinges are extremely similar. P. grata differs in having tiny, distinct crenulations on the inside of the anterior dorsal margin. T. semidecussata Reeve appears to be the same as this introduced species. Its colors are variable and commonly variegated. Alias T. bifurcata Quayle 1938. Genus Compsomyax R. Stewart 1930 Compsomyax subdiaphana Carpenter Milky Pacific Venus Plate 31f; figure 81a, b Alaska to Lower California. 1% to 2% inches in length, elongate-ovate, moderately inflated; beaks anterior and pointing forward. Sculpture of fine, irregular, concentric lines of growth, otherwise rather smoothish. Lunule poorly defined. 3 cardinal teeth in each valve, the most posterior one in the right valve deeply split. Color usually chalky-white, but younger specimens are yellowish white and semi-glossy. Interior white. Dredged in soft mud from 5 to 25 fathoms. Abundant in some Californian localities. Formerly placed in the genus Clementia. Figure 82. Psephidia of the Pacific Coast. a-b, P. Jordi Baird; ¢, P. ovalis Dall. Both ¥ inch. Genus Psephidia Dall 1902 Psephidia lordi Baird Lord’s Dwarf Venus Figure 82a Alaska to San Diego, California. ¥% inch in length, ovate, compressed or slightly fattened; beaks small; sculpture of microscopic, concentric growth lines. 3 cardinals in hinge of each valve. No laterals. On the dorsal margin there is a microscopic groove parallel to the edge. Color whitish to greenish white, commonly with darker, concentric color bands. Tiny young shells may be found inside the adult clams in the summer and spring months. Common. 412 American Seashells Genus [rus Oken 1815 Irus lamellifera Conrad Californian Irus Venus Plate 31r Monterey to San Diego, California. 1 to 1% inches in length, usually oblong, although some specimens may be almost round. Characterized by about a dozen, strongly raised, concentric lamellae or thin ridges. Shell whitish and with a chalky texture. Moderately common. Found burrowing in gray shale from low water to several fathoms. Subfamily MERETRICINAE Genus Tivela Link 1807 Tivela floridana Rehder Florida Tivela Palm Beach County, Florida. ¥g inch in length, subquadrate, beaks in the center, highly polished and with microscopic growth lines near the margins. Exterior glossy, tan or purplish. Interior mottled with purplish brown. This is the only Tivela recorded from eastern United States. Uncommon offshore. Subgenus Pachydesma Conrad 1854 Tivela stultorum Mawe Pismo Clam Plate 31h; figure 28d San Mateo County, California, to Lower California. 3 to 6 inches in length, ovate, heavy, moderately inflated, glossy-smooth, except for weak lines of growth. Ligament large and strong. Color brownish cream with wide, mauve, radial bands. Bands may be absent. Posterior end marked off by a single, sharp thread. Lunule lanceolate and with vertical scratches. Periostracum thin and varnish-like. A common and edible species. This is the only West Coast Tivela, but it has received a number of un- necessary names, T’. crassatelloides Stearns being one of many. Genus Transennella Dall 1883 Left anterior lateral fitting into a socket in the right valve. Internal margins are obliquely grooved with numerous, microscopic lines. These are parallel to the growth lines at the ventral margin of the valves. Transennella stimpsoni Dall Stumpson’s Transennella Pp Figure 83a, b North Carolina to southeast Florida and the Bahamas. VENERIDAE 413 ¥, to % inch in length, glossy, rounded trigonal in shape, smooth except for fine growth lines. Inner margins of valves creased with microscopic oblique threads. Exterior cream with 2 or 3 wide, radial bands of weak brown. Interior commonly flushed with purple. Pallial sinus long. Fairly common in shallow water. FicurE 83. Atlantic Transennella Clams. a and b, Transennella stimpsoni, ¥ inch; ce, T. conradina Dall, % inch. Transennella conradina Dall Conrad’s Transennella Figure 83c South half of Florida and the Bahamas. Shell very similar to that of stimpsoni, but differing in being pointed posteriorly, hence more elongate, and more variable in color. Zigzag brown lines present in some, others are solid cream or solid brownish. Exterior with fine, raised, concentric lines. Pallial sinus short. Common in shallow water. Transennella tantilla Gould Tantilla Transennella Alaska to Lower California. ¥Y, inch in length, ovate, angle at beaks about 90 degrees, smooth except for weak, concentric lines of growth. Immediately recognized under the hand lens by the tiny grooves running on the inside of the shell margins. Exterior cream with the posterior end stained bluish. Interior white with a wide, radial band of purple-brown at the posterior end. Dredged in large numbers off California and at times found washed ashore. “Pitarid” Group Beaks generally nearer the anterior end; cardinal teeth not tending to radiate; anterior laterals well-developed. 414 American Seashells Genus Pitar Romer 1857 Anterior left lateral fitting into a well-developed socket in the right valve. Middle left cardinal large; posterior right cardinal split. Subgenus Pitar s. str. Pitar fulminata Menke Lightning Venus Plate 39d North Carolina to Florida and the West Indies. 1 to 1% inches in length, plump, umbones large and full; lunule very large and outlined by an impressed line. Anterior end broader than the pos- terior end. Sculpture of crowded, rather heavy lines of growth. Exterior whitish with spots and/or zigzag markings of yellowish brown. Moderately common in shallow water. 43-inch young are commonly dredged off Miami. Pitar albida Gmelin of the West Indies is very similar, but all white in color, more quadrate in shape, has a narrower and more elongate lunule, and is usually more compressed. Common. Pitar morrhuana Linsle Morrhua Venus y Pl 1; fi ate 321; figure 81e Gulf of St. Lawrence to North Carolina. 1 to 1% inches in length, oval-elongate, moderately plump, with the lunule large and elongate. With numerous, heavy lines of growth. Color dull grayish to brownish red. P. fulminata is similar, but is found only to the south of Cape Hatteras, is not so elongate (compare figures), and is marked with brown. Fairly commonly dredged off New England. Pitar simpsom Dall Simpson’s Venus South half of Florida and the West Indies. %4 inch in length, plump, with fine, irregular, concentric threads; the large, ovate lunule is polished smooth. Color white to purplish white, com- monly with zigzag, yellow-brown markings. Escutcheon absent. Nearest in shape to #orrbuana. Uncommon at low tide to 26 fathoms. Subgenus Pitarenus Rehder and Abbott 1951 Pitar cordata Schwengel Schwengel’s Venus Plate 38n Off the Florida Keys and the Gulf of Mexico. 1% inches in length, very similar to morrhuana, but much fatter, with VENERIDAE 415 more distinct concentric threads on the outside, and with fine crenulations along the inside of the ventral margins of the valves. Interior white, com- monly with a pinkish blush. Dredged from 30 to 50 fathoms and brought in by shrimp fishermen. Uncommon. Subgenus Hysteroconcha P. Fischer 1887 Pitar dione Linné Royal Comb Venus Plate 30f Texas to Panama and the West Indies. 1 to 1% inches in length, characterized by its violet and purple-white colors and 2 radial rows of long spines at the posterior end of the valve. A common species washed ashore in Texas. The closely resembling species, Pitar lupanaria Lesson, occurs in the Pacific from Lower California to Peru. Genus Gouldia C. B. Adams 1845 Shell less than % inch in length; beaks minute; lunule long, bounded by an impressed line; no escutcheon. With concentric or reticulate sculpture. Anterior lateral teeth present. This genus is put in the separate subfamily Circinae by some workers. Gouldia cerina C. B. Adams Serene Gould Clam North Carolina to south half of Florida and the West Indies. ¥% inch in length, solid, trigonal in shape, beaks in the center, high and very small; lunule long, bounded by an impressed line; no escutcheon. Sculpture reticulate in which the fine, concentric ribs predominate. The radial ribs are stronger anteriorly. Color white, uncommonly with purplish or brownish flecks. A common species from shallow water to 95 fathoms. Genus Callista Poli 1791 Subgenus Costacallista Palmer 1927 Callista eucymata Dall Glory-of-the-Seas Venus Plate 391 North Carolina to south half of Florida, Texas and the West Indies. 1 to 1% inches in length, fairly thin, oval, with about 50 slightly flat- tened, concentric ribs which have a short dorsal and long ventral slope, and separated by a narrow, sharp groove. Color glossy-white to waxy pale- brown, with clouds and zigzag markings of reddish brown. No escutcheon. Margins rounded. A beautiful and rare species dredged from 25 to 110 fathoms. : 416 American Seashells Genus Macrocallista Meek 1876 Macrocallista nimbosa Solander Sunray Venus Plate 39b North Carolina to Florida and the Gulf States. 4 to 5 inches in length, elongate, compressed, glossy-smooth with a thin varnish-like periostracum. Exterior dull salmon to dull mauve with broken, radial bands of darker color. Interior dull white with a blush of reddish over the central area. Moderately common in shallow, sandy areas and not un- commonly washed ashore after storms. Macrocallista maculata Linné Calico Clam Plates 1b; 39e North Carolina to south half of Florida and the West Indies. 1% to 2% inches in length, ovate, glossy-smooth with a thin varnish-like periostracum. Exterior cream with checkerboard markings of brownish red. Rarely albino or all dark-brown. Moderately common in shallow, sandy areas in certain localities. A popular collector’s item. Also known as the Checker- board or Spotted Clam. Genus Callocardia A. Adams 1864 Subgenus Agriopoma Dall 1902 Callocardia texasiana Dall Texas Venus Plate 32k; figure 28¢ Northwest Florida to Texas. 1% to 3 inches in length, % as high. Externally resembling Pitar mor- rhuana, but much more elongate, having the beaks rolled in under themselves, and with a more elongate, faint lunule. The posterior cardinal is S-shaped in the right valve. Uncommon, if not rare. Found on the beaches, but its biology and habits are unknown. Genus Amiantis Carpenter 1863 Amiantis callosa Conrad Pacific White Venus Santa Monica, California, to south Mexico. 3 to 4% inches in length, longer than high, beaks pointing anteriorly, shell hard, heavy, glossy and with neat concentric ribs. Lunule small, heart- shaped and pressed in slightly under the beaks. Anterior end round. Color solid ivory. A very attractive, fairly common species living just below tide line on sandy bottoms in the open surf. Commonly washed ashore alive after VENERIDAE 417 storms between Seal Beach and Huntington Beach. Once known as C. nobilis Reeve. Genus Saxidomus Conrad 1837 Shell large, slightly gaping posteriorly, hinge with 4 or 5 cardinal teeth in the right valve, 4 in the left. Pallial sinus long and fairly narrow. Saxidomus nuttalli Conrad Common Washington Clam Plate 311 Humboldt Bay, California, to Lower California. 3 to 4 inches in length, oblong, with the beaks nearer the anterior end; heavy, with coarse, crowded, concentric ribs. Color a dull, dirty, reddish brown to gray with rust stains. Interior glossy-white, commonly with a flush of purple at the posterior margins. No lunule. Ligament large. Valves slightly gaping posteriorly. Young specimens less than 2 inches are thin- shelled, somewhat glossy and with pretty, mauve, radial streaks on the dorsal edge, both in front and behind the beaks. A very common species which is edible. Also called the Butter Clam. Saxidomus gigantea Deshayes Smooth Washington Clam Aleutian Islands to Monterey, California. Possibly this is only an ecologic variation or an example of a geographical gradient within a species. It is similar to typical nzttalli, but generally lacks the rust-stain color and rarely, if ever, develops the prominent concentric ridges. This is the commonest and best food clam in Alaska. Subfamily DOSINIINAE Genus Dosinia Scopoli 1777 Subgenus Dosinidia Dall 1902 Dosinia elegans Conrad Elegant Dosinia West Florida to Texas and south. 2 to 3 inches in length, circular, compressed, glossy, straw-yellow with numerous even, concentric ridges (20 to 25 per inch in adults). Moderately common. Do not confuse with D. discus. Dosinia discus Reeve Disk Dosinia Plate 38-0; figure 81c Virginia to Florida, the Gulf States and the Bahamas. 418 American Seashells 2 to 3 inches in length, similar to e/egams, but having more and finer concentric ridges (about 50 per inch in adults), and not so circular. Com- monly washed ashore in perfect condition after storms along the Carolina coasts and middle western Florida. Subfamily EMMINAE Very small shells, with marginal grooves and denticles simulating lateral teeth. Inner ventral margins crenulate. Figure 84, Amethyst Gem Clam. a and b, Gemma gemma Totten, % inch; ¢ to e, the form purpurea Lea, % inch. Genus Gemma Deshayes 1853 Shell the size and shape of a split-pea; lunule large, faintly impressed; no escutcheon; 2 large teeth in the left valve with a large, median socket between the two. A very thin ridge which might be termed a tooth occurs posteriorly beneath the ligament. 3 teeth in right valve. Pallial sinus small and triangular. The shells of the brooded young may be found inside some females. Gemma gemma Yotten Amethyst Gem Clam Plate 38k; figure 84 Nova Scotia to Florida, Texas and the Bahamas. Puget Sound, Wash- ington (introduced). ¥s inch in length, subtrigonal, moderately inflated and rather thin-shelled. Fxterior polished and with numerous, fine, concentric furrows or riblets. PED RICO DAE 419 Color whitish to tan with purplish over the beak and posterior areas. Pallial sinus commonly, but not always, about the length of the posterior muscle scar. It points upward. This is a very common shallow-water species. A number of subspecies or forms have been described, but their validity needs clarification: purpurea Lea (fig. 84c to e), manhattensis Prime and fretensis Rehder. Genus Parastarte Conrad 1862 Shell the size of a split-pea, very similar to Gemma. In Parastarte, the ligament is high and situated beneath the beak, occupying a very high and broad area. In Gemma, the ligament is very narrow and elongated, and ex- tending posterior to the beaks. Pallial sinus much smaller in Parastarte. PEGE WS oN AY V4 > Ficure 85. Brown Gem Clam, Parastarte triquetra Conrad, % inch (Florida). Parastarte triquetra Conrad Brown Gem Clam Figure 85 Both sides of Florida (to Texas?). % inch in size, very similar to Gemma gemma, but much higher than long, with the beaks larger and elevated. Exterior highly polished and smoothish. Color usually tan to brown, but may be flushed with pink in beachworn specimens. The pallial sinus is almost absent. Moderately com- mon on sand bars and obtained by screening the sand. Family PETRICOLIDAE Subfamily PETRICOLINAE Genus Petricola Lamarck 1801 Subgenus Naranio Gray 1853 Petricola lapicida Gmelin Boring Petricola South half of Florida and the West Indies. ¥% inch in length (up to 1% inches in the Lesser Antilles), ovate, in- flated, chalk-white, with criss-cross, threaded sculpturing. Beaks swollen and 420 American Seashells close together. Posterior end with wavy ribs consisting of fine mud particles laid down over the shell by the animal. There is an enclosed, elongate fur- row between the beaks and the hinge. Color yellowish white. Found in burrow holes in coral rocks. Not uncommon. Subgenus Petricolaria Stoliczka 1870 Petricola pholadiformis Lamarck False Angel Wing Plate 32z; figure 4b Gulf of St. Lawrence to the Gulf of Mexico and south. 2 inches in length, elongate, rather fragile and chalky-white. With numerous radial ribs. The anterior ro or so are larger and bear prominent scales. Ligament external, located just posterior to the beaks. Cardinal teeth quite long and pointed. The siphons are translucent-gray, large, tubular and separated from each other almost to their bases. A very common clay and peat-moss borrower. Genus Rupellaria Fleuriau 1802 Rupellaria typica Jonas Atlantic Rupellaria Plate 30e North Carolina to the south half of Florida and the West Indies. About 1 inch in length, oblong, flattened anteriorly; compressed, usually attenuated and gaping posteriorly. Beaks point anteriorly. Exterior gray or whitish and with numerous, irregularly spaced, coarse radial ribs. Interior uneven and brownish gray. This coral borer is variable in shape and uneven in texture. It may also be truncate at the posterior end. Moderately common. Rupellaria tellimyalis Carpenter West Coast Rupellaria Plate 31t Santa Monica, California, to Mazatlan, Mexico. 1 to 1% inches in length. Oblong-elongate, variable in shape and out- line due to crowding in the rock burrow. Shell fairly thick, white, except for purplish blotches commonly behind the hinge and at the posterior end. Radial threads are coarser at the anterior end. Growth lines are irregular and coarse. Pallial sinus broadly rounded at its anterior end. Early or nep- ionic shell is shaped somewhat like a Donax, smooth, translucent purplish brown and rarely found attached at this early stage to rocks and kelp stalks. R. californiensis Pilsbry and Lowe is identical. Rupellaria denticulata Sowerby known only from Peru has a similar nepionic shell (contrary to other reports), has a narrower, triangular pallial sinus, and (contrary to reports) is a more fragile shell. Its anterior end is TELLINIDAE 421 pointed and slightly uplifted. Interior blushed with mottlings of chestnut to purplish brown. Rupellaria carditoides Conrad Hearty Rupellaria Vancouver, B.C., to Lower California. 1 to 2 inches in length. Very variable in shape, usually oblong; in some, squat and almost orbicular. Shell white to grayish white and very chalky in texture. Concentric growth lines quite coarse and irregular. Radial sculpture of peculiar, fine, scratched lines crowded together, but worn away in some specimens. Fairly common. Found boring into hard rock. Nepionic shell usually oblong. R. californica Conrad is the same. Subfamily COOPERELLINAE Genus Cooperella Carpenter 1864 Hinge plate narrow, with 2 right and 3 left short, divaricating cardinals under the beaks. The left central cardinal is always, and the others com- monly, split or bifid. No laterals. Muscle scars small and oval. Pallial line narrow, the sinus long. Cooperella subdiaphana Carpenter Shiny Cooper’s Clam Southern California to Lower California. About ¥ inch in length, oval-oblong, opaque-white with a brilliant gloss and slight opalescence. Fragile. Outer surface with slightly wavy concentric growth lines. Ligament tiny, short, set just behind the beaks and visible ex- ternally. Moderately common offshore to 40 fathoms. Superfamily TELLINACEA Family TELLINIDAE Genus Tellina Linné 1758 Subgenus Tellina s. str. Tellina radiata Linné Sunrise Tellin Plate 4oe South Carolina to south half of Florida and the West Indies. 2 to 4 inches in length, elongate, moderately inflated. Characterized by its oily smooth, glistening surface and rich display of colors—either creamy- white or rayed with pale-red or yellow. Interior flushed with yellow. The beaks are usually tipped with bright-red. Uncommon in Florida but abundant in the West Indies. 422 American Seashells Tellina laevigata Linné Smooth Tellin Plate 4ok Southern Florida and the West Indies. 2 to 3 inches in length, oval to slightly elongate, moderately compressed, strong, with a smooth, glossy surface except for microscopic, radial scratches. Exterior color either whitish or usually faintly rayed, or banded at the ven- tral margins with soft, creamy-orange. Inside polished white to yellowish. Rare in Florida, fairly common in the West Indies. Subgenus Tellinella Morch 1853 Tellina interrupta Wood Speckled Tellin Plate 4ol North Carolina to south half of Florida and the West Indies. 2% to 3% inches in length, well elongated, moderately inflated, twisted at the posterior end where at the dorsal margin on the right valve there are 2 rough ridges. Concentric threads numerous, evenly spaced. Color whitish with numerous small, prominent, zigzag specklings of purplish brown. Inte- rior yellowish. Not uncommon in southeast Florida, but abundant in some shallow West Indian bays. Tellina idae Dall Ida’s Tellin Figures 87a, b; 28h Santa Monica to Newport Bay, California. 2 to 2% inches in length, elongate, compressed. With strong, rather evenly spaced, concentric, lamellate threads. Posterior end narrow, slightly twisted and with a rounded, radial ridge near the dorsal margin (in right valve) or a ridge at the dorsal margin and a furrow below it (left valve). Ligament elongate and sunk deeply into the long, deep dorsal-margin furrow. Color grayish white. Moderately common. Subgenus Angulus Miuhlfeld 1811 Tellina agilis Stimpson Northern Dwarf Tellin Plate 30x; figure 86f Gulf of St. Lawrence to North Carolina. ¥ to % inch in length, moderately elongate, compressed, fairly fragile; glossy-white externally with an opalescent sheen. Interior white. Ligament external and prominent. With a large rounded pallial sinus almost extending to the anterior muscle scar. External sculpture of faint, microscopic, con- centric, impressed lines. Commonly found washed on shore from Maryland north, Formerly known as Tellina tenera Say and Angulus tener Say (not TELLINIDAE 423 Schrank 1803 nor Leach 1818). In 1858, W. Stimpson gave this species a new name (Amer. Journ. Sci., vol. 25, p. 125). T. elucens Mighels might be this species, although it is very doubtful. Tellina texana Dall replaces this species in the Gulf of Mexico. It has more distinct, crowded concentric lines, is more inflated and has very small, microscopic striae in most specimens. Compare with T. versicolor. Ficure 86. Interior views of southeast coast Tellins, showing outline shapes and pallial sinus scars. a, Tellina lineata Turton, 1% inches; b, T. tampaensis Conrad, Y% inch; ec, T. mera Say and promera Dall, *4 inch; d, T. sybaritica Dall, ¥% inch, e, T. similis Sowerby, 1 inch; f, T. agilis Stimpson and sayi Dall, % inch; g, Quadrans lintea Conrad, *4 inch; h, Phylloda squamifera Deshayes, 34 inch. Tellina versicolor DeKay DeKay’s Dwarf Tellin New York to the south half of Florida and the West Indies. % inch in length, very similar to T. agilis, but more elongate, colored white, red, pink or rayed, is more inflated, and has a nearly straight instead of curved ventral margin. The exterior of versicolor has a brighter irides- cence. The pallial sinus is much closer to the anterior muscle scar. Tellina mera Say Mera Tellin Figure 86c Eastern Florida and the Bahamas. % to % inch in length, roughly elliptical, moderately inflated, pure opaque-white in color. Fairly thin but strong. Beaks fairly large for a ‘Tellin, touching and pointing toward each other and located nearer the posterior than the center of the shell. The valves show hardly any posterior bend or twist. Exterior smoothish with fine, irregular, concentric lines of growth more evident near the margins. Moderately common in shallow water be- tween tides, Compare with promera and tampaensis, 424 American Seashells Tellina promera Dall Promera Tellin Figure 86c South half of Florida and the West Indies. %4 inch in length, very similar to mera, but larger, more inflated, thicker- shelled, more oval and with the umbones a little closer to the center of the shell. This may be only a subspecies of mera. Quite common on both sides of Florida. Tellina tampaensis Conrad Tampa Tellin Figure 86b South half of Florida to Texas, the Bahamas and Cuba. % to % inch in length, similar to mera, but more pointed posteriorly, whitish with a faint pinkish blush, and with very numerous, microscopic, concentric lines of growth. The pallial sinus line in this species runs forward nearly to the anterior muscle scar and then drops almost vertically toward the ventral margin of the shell before continuing posteriorly. In mera and promera, the pallial sinus line toward the anterior muscle scar, makes a U-shaped turn, and then runs posteriorly but does not join the lower pallial line until about the middle of the ventral region of the valve. Common in shallow water. Tellina texana Dall Say’s Tellin New Jersey to south half of Florida and Cuba. % inch in length, white with a faint opalescent sheen. Extremely close to agilis, but distinguished by the heavy, enamel-white finish on the inside of the shell and 1 or 2 fairly distinct radial grooves running from the poste- rior muscle scar to the ventral margin of the valve. The faint pallial sinus just touches the anterior muscle scar. Fairly common. T. sayz Dall (Dec. 1900) is a synonym of T. texana Dall (Nov. 1900). T. polita Say (not Spengler) is also this species. Tellina sybaritica Dall Dall’s Dwarf Tellin Figure 86d North Carolina, the Gulf of Mexico and Cuba. % to % inch in length, very elongate, shiny, with quite strong, nu- merous concentric threads or cut lines. Color varying from translucent-white, yellowish, pinkish to bright watermelon-red. Our smallest and most colorful Tellin, and plentiful from 1 to 60 fathoms. It somewhat resembles young alternata, but the latter are smoother and have a short instead of long poste- rior lateral tooth in the left valve, and has no lateral lamina in the left valve. PELLINIDAE 425 Section Oudardia Monterosato 1885 Tellina modesta Carpenter Modest Tellin Plate 31u Alaska to the Gulf of California. %4 to 1 inch in length, elongate, moderately pointed at the posterior lower corner. Surface white with iridescent sheen and with fine concentric threads or grooves. These fade out at the posterior fourth of the shell, but reappear more coarsely on the very posterior slope. There is a well-formed, radial rib inside just behind the anterior muscle scar. Common in certain sandy localities from shore to 25 fathoms. It appears that I. buttoni Dall is the same species. cand d, Tellina lutea Wood, 3 inches (Alaska). Section Peronidia Dall 1900 Tellina lutea Wood Great Alaskan Tellin Figure 87c, d Arctic Ocean to Cook’s Inlet, Alaska. Japan. 3 to 4 inches in length, elongate, quite compressed, and with a posterior twist to the right. Worn shells chalky-white, commonly with a pink flush. Periostracum in young is greenish yellow and glossy; in adults dark-brown. Ligament prominent. Commonly found from beach to 23 fathoms. T. venu- losa Schrenck 1861 is an ecologic form with brownish cracks in the shell. 426 American Seashells Subgenus Moerella Fischer 1887 Tellina salmonea Carpenter Salmon Tellin Plate 31y Aleutian Islands to San Pedro, California. % inch in length, ovalish, with a short, blunt posterior end. Ligament behind the beaks prominent. Dorsal margin in front of beaks almost straight. Color chalky-white, commonly with a pinkish cast. Periostracum smooth, thin, yellowish tan. Characterized by about 4 to 7 prominent, concentric, former growth-stop lines which are usually stained dark-brown. Common from low tide to 34 fathoms in sand. Do not confuse with meropsis. Tellina meropsis Dall Meropsis Tellin Plate 30u San Diego, California, to the Gulf of California. % inch in length, ovalish, pure white, smoothish, with exceedingly fine growth lines. Surface silky, but rarely with an iridescent sheen. Beaks slightly toward the posterior end. Ligament not prominent and light-brown. Without growth stoppage lines. See T. salmonea. Common from shore to 15 fathoms. Tellina carpenteri Dall Carpenter’s Tellin Forrester Island, Alaska, to the Gulf of California. 44 inch in length, moderately elongate, with a rounded anterior end and rather truncate posterior end. Ligament short. Color cream, whitish and commonly blushed with watermelon-pink inside and out. It also has a faint iridescent sheen. Found very abundantly in many localities in mud and sand from shore to 369 fathoms. Subgenus Scissula Dall 1900 Tellina similis Sowerby Candy Stick Tellin Plate 4om, figure 86e South half of Florida, the Bahamas and western Caribbean. 1 inch in length, moderately elongate, moderately compressed, thin but fairly strong. Color opaque-white with a yellowish blush and with 6 to 12 short radial rays of red. Interior yellowish with red rays or solid pink or yellow. A red splotch commonly occurs on the hinge in front of the cardinal teeth. Sculpture of concentric growth lines and numerous fine concentric threads which cross the shell at an oblique angle. Common on sand fiats. V. decora Say is the same species. TELLINIDAE 427 Tellina iris Say Iris Tellin North Carolina to Florida, the Gulf of Mexico, and Bermuda. ¥% inch in length, very similar to similis, and often as colorful, but very thin-shelled, translucent and more elongate. On the interior of the valves, the wavy oblique lines are evident, and there are 2 radial thickenings or weak, white, internal ribs at the posterior end. Common from intertidal flats to 20 fathoms. Tellina candeana Orbigny from the Lower Florida Keys and the West Indies commonly yellowish white and is more wedge-shaped (blunter at the anterior end) and, of course, has the peculiar sculpture of this subgenus. Subgenus Scrobiculina Dall 1900 Tellina magna Spengler Great Tellin Plate 4oi North Carolina to southeast Florida and the West Indies. 3 to 4% inches in length, half as high, quite compressed and glossy- smooth. Posterior dorsal region dull, bordered by a weak, radial ridge. Left valve glossy white, rarely faintly yellowish, right valve glossy orange to pinkish and microscopically cut with concentric scratches. An uncommon and very lovely species much sought after by collectors. Found just below low tide in sand. Subgenus Eurytellina P. Fischer 1887 Tellina lineata Turton Rose Petal Tellin Plate goh All of Florida and the West Indies. 1% inches in length, moderately elongate, slightly inflated, solid and with a fairly strong twist to the right at the posterior end. Smoothish and glossy, but under a lens fine, concentric, crowded grooves may be seen. The outer surface has a slight opalescent sheen. Color pure-white or strongly flushed with watermelon-red. Pallial sinus just touches the anterior muscle scar, while in the similar but more elongate T. alternata it does not. Com- mon in shallow water. Tellina alternata Say Alternate Tellin Plate gon North Carolina, Florida, and the Gulf States. 2 to 3 inches in length, elongate and compressed, solid, and with a moderately pointed and slightly twisted posterior end. Sculpture of numer- 428 American Seashells ous evenly spaced, fine, concentric grooves. Area near umbones smooth. Color glossy and variable: whitish, yellowish or flushed with pink. Interior glossy-yellow or pinkish. A common shallow-water species which should always be compared with Jineata. The similar Tellina angulosa Gmelin from the Keys and West Indies is not so elongate, has finer grooves and a more highly glossed surface which is commonly covered with a greenish-yellow, thin periostracum. Common in sand. T. punicea Born (which Dall called angulosa Gmelin) from the Keys (rare) and West Indies (common) is similar, but is always bright water- melon-red internally and purplish red exteriorly. The pallial sinus just touches the anterior muscle scar, which it does not in alternata or angulosa. Genus Arcopagia Brown 1827 Subgenus Cyclotellina Cossmann 1886 Arcopagia fausta Pulteney 1799 Faust Tellin Plate 40] North Carolina to southeast Florida and the West Indies. 2 to 4 inches in length, oval, moderately inflated, fairly heavy, and smoothish, except for small, rough, concentric lines of growth. Hinge strong, the posterior lateral in the right valve being long and strong. Color outside a semi-glossy-white; inside highly glossed and enamel-white with a yellowish flush. Do not confuse with T. laevigata which is glossy outside and has orange-tinted margins. Moderately common in the West Indies. Donovan gave this species the same name in 1801. Genus Strigilla Turton 1822 Tellin-like shells, usually oval in shape and with inconspicuous growth lines crossed by fine, oblique, cut lines. There are only four species in the western Atlantic. Strigilla carnaria Linné Large Strigilla Plate 4oc North Carolina to Florida and western Caribbean. %4 to 1 inch in length, oval, slightly oblique, moderately compressed, fairly thin but strong. Outer surface finely sculptured by cut lines which are obliquely radial in the central and posterior regions of the valve. At the anterior third of the valve, there are wavy, oblique threads running in the opposite direction. Exterior pinkish white with former, concentric growth stages a deeper pink. Interior bright watermelon-red. The upper line of TELLINIDAE 429 the pallial sinus runs directly posterior to the anterior muscle scar. Common in shallow water in sand and commonly washed ashore. West Indian collectors should not confuse this species with Strigilla rombergi Morch (southeast Florida, the Bahamas to Lesser Antilles) which is very similar, except that the upper line of the pallial sinus does not reach the anterior muscle scar. The radial cut lines are more numerous and more curved in rombergi. Common. Strigilla mirabilis Philippi White Strigilla North Carolina to Florida, Texas and the West Indies. ¥ inch in length, oval, inflated, shiny, all white in color and with the peculiar Strigillid sculpturing which is very similar to that in S. pisiformis (the radial cut lines meet the ventral margin of the valves at an angle of about 45 degrees). The pallial line runs forward from the posterior muscle scar but does not reach the anterior muscle scar as it does in pisiformis. Common. Do not confuse with the larger Divaricella quadrisulcata (page 391) which has fine denticulations on the inner margins of the valves. S. flexuosa Say 1822 is preoccupied by Montagu 1803 and Turton 1807, and must take the name mirabilis Philippi 1841. Strigilla pisiformis Linné Pea Strigilla Florida Keys, the Bahamas and the West Indies. ¥s inch in length, similar to S. carnaria, but always much smaller and more inflated. The pink color inside is concentrated in the deepest part of the valve, and the margins are usually white. The radial, oblique cut lines meet the ventral margin of the valve at about 45 degrees angle, while in carnaria the lines are almost vertical. This is a very abundant species, es- pecially in the Bahamas where they are gathered in great numbers and brought to Florida for use in the shellcraft business. Genus Phylloda Schumacher 1817 Subgenus Phyllodina Dall 1900 Phylloda squamifera Deshayes Crenulate Tellin Figure 86h North Carolina to the south half of Florida. % to 1 inch in length, elongate, concentrically and finely ridged. Char- acterized by the strong crenulations on the posterior dorsal margin and by the lightly hooked-down posterior ventral margin. Color whitish with a yellow or orangish tint. Moderately common from low water to 60 fathoms. 430 American Seashells Compare with Jintea which lacks the dorsal crenulations. Formerly placed in the genus Tellina. Genus Quadrans Bertin 1878 Quadrans lintea Conrad Lintea Tellin Figure 86g North Carolina to both sides of Florida and the West Indies. *4 to 1 inch in length, moderately oval, slightly inflated, quite strong and all white in color. Posterior dorsal slope with 2 radial ridges in the right valve, 1 in the left. Concentric lamellae numerous, sharp and minutely raised. Left valve with 2 extremely weak, long laterals, but these are well- developed in the right valve. Dorsal line of the pallial sinus meets the pallial line not far from the anterior muscle scar. Posterior twist to the right is fairly pronounced. Commonly dredged off the Carolinas (9g to 16 fathoms), uncommonly found in a few feet of water on the west coast of Florida. Formerly placed in Tellina. Genus Tellidora H. and A. Adams 1856 Tellidora cristata Recluz White Crested Tellin Plate 30-0 North Carolina to west Florida and Texas. 1 to 1% inches in length, roughly ovate, compressed and all white. The left valve is very flat, the right valve slightly inflated. Dorsal margins of valves with large, saw-tooth crenulations. A bizarre clam found un- commonly in shallow water. Genus Macoma Leach 1819 The Macomas are modified tellins which may be distinguished by (1) no lateral teeth; (2) usually dingy-white in color and of a chalky consistency; (3) there is a strong posterior twist; (4) the pallial sinus is larger in one valve than the other. Macoma calcarea Gmelin Chalky Macoma Figure 88f Greenland to Long Island, New York. Bering Sea to off Monterey, California. 1% to 2 inches in length. Oval-elongate, moderately compressed, but somewhat inflated at the larger, anterior half. Beaks *5 the way toward the narrowed, slightly twisted posterior end. Shell dull, chalky-white. Con- TELLINIDAE 43] centric sculpture of fine, irregular threads. Periostracum remaining on the margins 1s gray. Pallial sinus in left valve runs from the posterior muscle scar anteriorly toward the anterior muscle scar, but does not meet the latter, and then descends posteriorly to meet the pallial line about the middle of the lower margin of the shell. A common cold-water species, distinguished from balthica by its larger size, more elongate shape and pattern of the pallial sinus scar (see fig. 88¢). Y o OY GO Gg OO Figure 88. American Macomas, showing interior scars. a, Macoma brota Dall, 3 inches (Alaska to Washington); b, M. incongrua von Martens, 2 inches (Alaska to Washington); c, M. secta Conrad, 3 inches (Pacific Coast); d, M. nasuta Conrad, 2 inches (Pacific Coast); e, M. irus Hanley, 2 inches (Pacific Coast); f, M. calcarea Gmelin, 2 inches (Atlantic and Pacific Coasts); g, M. balthica Linné, 1 inch (Atlantic and Pacific Coasts); h, Mf. planiuscula Grant and Gale, 1 inch (Alaska to Washington). Macoma balthica Linné Balthic Macoma Figure 88g Arctic Seas to off Georgia. Bering Sea to off Monterey, California. % to 1% inches in length, oval, moderately compressed. Color dull whitish, in some with a flush of pink, and with a thin, grayish periostracum which readily flakes off. The shape is somewhat variable. A common inter- tidal and deep-water species. Compare muscle scars with those of calcarea. Macoma tenta Say Tenta Macoma Cape Cod to south half of Florida and the West Indies. 432 American Seashells % to % inch in length, fragile, elongate, white in color with a delicate iridescence on the smooth exterior. Posterior and narrower end slightly twisted to the left. This small, tellin-like species is very common in shallow water in sand. MM. souleyetiana Recluz is the same. Macoma limula Dall is very similar in size and shape, although somewhat more elongate, and is distinguished by the finely granular external surface of the valves. Commonly dredged from North Carolina to Florida. Macoma constricta Bruguiere Constricted Macoma Florida to Texas sil the West Indies. 1 to 2% inches in length, moderately elongate. The posterior end 1s twisted to the right and is narrowed to a blunt point. Color all white with concentric growth lines stained by the gray periostracum. Common just off- shore. Macoma nasuta Conrad Bent-nose Macoma Figure 88d Alaska to Lower California. 2 to 3% inches in length, elongate, rather compressed and strongly twisted to the right at its posterior end. Beaks slightly nearer the anterior end. Can be distinguished from other Pacific Coast species by the pallial sinus in the Jeft valve which reaches the anterior muscle scar. One of the commonest species on the west coast and lives about 6 inches below the surface of the mud in quiet waters from shore to 25 fathoms. Macoma secta Conrad White Sand Macoma Figure 88c Vancouver Island to the Gulf of California. 2 to 4 inches in length. This is the largest Macoma in America and 1s characterized by the almost flat left valve, rather well-inflated right valve, and by the wide and relatively short ligament which is sunk partially into the shell. There is a large, oblique, rib-like extension just behind the hinge inside each valve. Color cream to white. Common in bays and beaches from shore to 25 fathoms. A small form occurs in protected waters in bays in its more southerly range. Students of the Pacific Coast fauna consider M. imdentata Carpenter (same range) as a distinct species in which the shell is 1% inches in length, a little more elongate, with a more pointed posterior end, and with a slight indentation on the posterior ventral margin. It may possibly be a form of young secta. M. tenmirostris Dall is even more elongate and may also be a form. TELLINIDAE 433 Macoma yoldiformis Carpenter Yoldia-shaped Macoma Alaska to San Diego, California. % to % inch in length, elongate, moderately rounded at each end and with a small, but distinct, twist to the right at the posterior end. Color a uniform, glossy, porcellaneous white. Rarely translucent with an opalescent sheen. Common from shore to 25 fathoms. Macoma carlottensis Whiteaves Queen Charlotte Macoma Arctic Ocean to Lower California. About 1 inch in length, extremely fragile, inflated and with a very short, inconspicuous ligament. Color translucent-white with a thin, greenish, glossy periostracum. This species was named imflatula Dall at a later date. Macoma brota Dall Brota Macoma Figure 88a Arctic Ocean to Puget Sound, Washington. 3 inches in length, moderately elongate, moderately inflated and rather thick-shelled. Beaks 73 toward the posterior end. Resembles calcarea whose pallial sinus in the left valve, however, 1s more elongate, not as high and generally reaches nearer the anterior muscle scar. M. brota is larger and more truncate posteriorly than that species. Common, Macoma planiuscula Grant and Gale Grant and Gale Macoma Plate 30t; figure 88h Arctic Ocean to Puget Sound, Washington. About 1 inch in length. Extremely similar to calcarea, but porcellaneous, with a glossy, yellowish periostracum and more oval in shape. This species was thought by Dall and others to be “‘carlottensis Whiteaves.” Genus Gastrana Schumacher 1817 Subgenus Heteromacoma Habe 1952 Gastrana irus Hanley Irus Macoma Figure 88e Bering Sea to Los Angeles, California. Japan. Commonly 1% inches in length (rarely 3); oval-elongate, moderately inflated, very slightly twisted, if at all, at the posterior end. Pallial sinus in left valve almost reaches the bottom of the anterior muscle scar. Beaks slightly anterior. Common in Washington and Oregon. Formerly known as inquinata Deshayes. 434 American Seashells Macoma incongrua von Martens (fig. 88b) (Alaska to Washington) is similar, but more oval, with a more pointed slope at the beaks, a straighter posterior dorsal edge. Its upper pallial sinus line, after nearly reaching the anterior muscle scar, turns downward and then runs anteriorly before con- necting with the pallial sinus. Common in Alaska. Genus Apolymetis Salisbury 1929 Apolymetis imtastriata Say Atlantic Grooved Macoma Plate 32y South half of Florida and the Caribbean. 2 to 3 inches in length, elliptical, fairly thin but strong and all white in color. The shell is strongly twisted. At the posterior end, the right valve bears a strong, radial rib, while on the left valve there is a fairly strong, radial groove. Pallial sinus very large. Living specimens are not commonly col- lected, although shells are commonly washed ashore. Apolymetis biangulata Carpenter Pacific Grooved Macoma Santa Barbara, California, to Ensenada, Mexico. 2 to 3% inches in length, oval, moderately compressed, strong, and dull grayish white in color. Interior glossy-white with the central portion blushed with pastel-peach. Left valve with a shallow, radial groove near the posterior end. Right valve with a corresponding ridge at the end of which the margin of the shell is shallowly notched. Alias A. alta Conrad. Common. Family SEMELIDAE Genus Semele Schumacher 1817 Resilium supported in a horizontal, chondrophore-like depression which is internal and parallel with the hinge line. 2 cardinal teeth in each valve. Right valve with 2 distinct lateral teeth, but practically absent in the left valve. The ligament is external. Semele proficua Pultene White Atlantic Semele p y Plate 4og North Carolina to south half of Florida and the West Indies. ¥% to 1¥% inches in length, almost round, beaks almost central. Lunule small and pushed in. Fine concentric lines and microscopic radial striations. Externally whitish to yellowish white. Interior glossy, commonly yellowish, rarely speckled a little with purple or pink. Moderately common in shallow water. The color form radiata Say, has a few indistinct radial rays of pink (pl. 4of). SEMELIDAE 435 Semele purpurascens Gmelin Purplish Semele Plate 4ob North Carolina to south half of Florida and the West Indies. 1 to 14 inches in length, oblong, thin-shelled, smooth except for very fine concentric growth threads over which run another set of fine, micro- scopic concentric lines at an oblique angle. External color variable: com- monly gray or cream with purple or orangish mottlings. Interior glossy and suffused with purple, brownish or orange. A fairly common, shallow-water species. Semele bellastriata Conrad Cancellate Semele Plate 30j North Carolina to south half of Florida and the West Indies. % to %4 inch in length, similar in shape to purpurascens, but a much smaller species with numerous radial and concentric riblets which cross to give a cancellate appearance. Some specimens well-beaded, others have the radial ribs more prominent. External color yellowish white with reddish flecks or a solid, purplish gray. Interior white, cream or suffused with mauve or violet. S. cancellata Orbigny is this species, Fairly common just offshore. Semele rubropicta Dall Rose Petal Semele Plate 29w Alaska to Mexico. 1 to 1% inches in length; beaks % toward the posterior end; rather thick-shelled, especially in the south. Concentric sculpture of small, irreg- ular growth lines. Radial incised lines numerous. Periostracum thin, smooth and yellowish brown. Exterior of shell dull grayish or tannish white with faint, radial rays of light-mauve. Interior glossy-white, with a small splotch of mauve at both ends of the hinge line. Uncommon from 20 to 50 fathoms. Semele rupicola Dall Rock-dwelling Semele Plate 20t Santa Cruz, California, to the Gulf of California. 1 to 1% inches in length. Irregular in shape: ovalish, oval-elongate or obliquely oval. Exterior yellowish cream with numerous, concentric crinkles and a few weak radial threads. Interior glossy, white at the center, bright purplish red at the margins and hinge. John Q. Burch finds this species com- mon in Chama and Mytilus beds and in rocks and crevices. Semele decisa Conrad Bark Semele Plate 29z San Pedro, California, to Lower California. 436 American Seashells 2 to 3 inches in length, equally high. Characterized by its heavy shell, by the coarse, wide, irregular, concentric folds on the outside (resembling rotting bark or wood). Exterior yellowish gray; interior glossy-white, with a purple tinge, especially prominent on the hinge and margins. Commonly found in rocky rubble in shallow water. Genus Cumingia Sowerby 1833 Shell delicate, with concentric lamellae; slightly gaping behind. Resilium internal and supported by a spoon-shaped chondrophore. One cardinal and 2 elongate lateral teeth in each valve. Cumingia tellinoides Conrad Tellin-like Cumingia Nova Scotia to St. Augustine, Florida. % to % inch in length, oblong and fairly thin. Slightly pointed at the posterior end. Exterior chalky-white, with tiny, sharp, concentric lines. This is a moderately common mud-digger which externally resembles a Tellina. The subspecies vanhyningi Ronde: 1939 replaces the typical species in southern Florida to Texas. It is not so high, is more elongate and more drawn out posteriorly. Common in shallow water. C. coarctata Sowerby (Lower Keys and West Indies) has stronger, more widely separated con- centric ridges. Cumingia californica Conrad Californian Cumingia Plate 31v Crescent City, California, to Chile. 1 to 17% inches in length, elongate-oval, moderately compressed. In front of the beaks there is a small, elongate depression. Just posterior to and partially covered by the inrolled beaks is a small, short ligament, posterior to which is a wide, flaring furrow. Concentric sculpture of numerous wavy, rather sharp, fairly large threads. Color grayish white. Pallial sinus very long. Abundant in rock crevices and wharf pilings. Also dredged down to 25 fathoms. Genus Abra Lamarck 1818 Shell small (%4 inch), fragile, ovalish, smooth, moderately compressed. Translucent-white in color. Resilium internal and supported by a linear chondrophore. Right valve with 2 cardinals and generally with 2 lamellar laterals. DONACIDAE ap) Abra aequalis Say Common Atlantic Abra Plate 30v North Carolina to Texas and the West Indies. Y, inch in size, orbicular, smooth, glossy and rather inflated. Surface may show a slight iridescence. Periostracum very thin and clear yellowish. Anterior margin of right valve grooved. A very abundant and very simple- looking bivalve. Compare with Jioica. Abra lioica Dall . Dall’s Little Abra Plate 30w Cape Cod to south Florida and the West Indies. Y4 inch in size, similar to aequalis, but the beaks are nearer the anterior end, the shell is thinner, and more elongate. Anterior margin of right valve not grooved. The prodissoconch at the beaks is large, tan and more trigonal in shape than the adult. Common from 6 to 200 fathoms. Family DONACIDAE Genus Donax Linné 1758 The posterior end is the shortest and the fattest. 2 cardinal and an ante- rior and a posterior lateral in each valve. Pallial sinus deep. Donax variabilis Say Cogquina Shell Plate 30r Virginia to south Florida and Texas. ¥% to % inch in length. Ventral margin of the valves straight and almost parallel with the dorsal margin. The thinner, anterior end is commonly smooth, but may be microscopically scratched with radial lines. From the middle of the valve to the blunt posterior end, small radial threads appear which become increasingly larger posteriorly. Internal margin of valves minutely denticulate. Color variable and commonly very bright, especially inside: white, yellow, pink, purple, bluish, mauve and commonly with rays of darker shades. The subspecies roemeri Philippi (pl. 30q) is very common along the Texas shores. The posterior end is blunter, the whole shell not so elongate, and the ventral margin sags down. Donax fossor Say Fossor Donax Long Island, New York, to Cape May, New Jersey. Never exceeds % inch in length, very similar to variabilis, but almost (=) ’ yf 5) 438 American Seashells smooth, even at the blunt, posterior end. Only 2 color phases: yellowish white or with weak purplish rays. Subsequent biological studies may show that this common beach species is a subspecies or cold-water form of varia- bilis. Young specimens of variabilis from several southern states look suspi- ciously like this so-called species. Donax tumidus Philippi Fat Gulf Donax Northern shores of the Gulf of Mexico. ¥, to % inch in length, very obese, somewhat trigonal in shape, with its beaks swollen and posterior end strongly truncate. Threads on the blunt posterior end are heavily beaded, sometimes giving a cancellate appearance. Narrow anterior end commonly with distinct, microscopic, distantly spaced, incised, concentric lines. Color whitish with bluish, yellowish or pinkish undertones. Rarely, if ever, rayed. Uncommon. Found in 2 to 3 feet of water. Donax denticulatus Linne (pl. 30p) from the southwest Caribbean has been erroneously recorded from our shores. It is 1 inch in length and char- acterized by 2 curved, low ridges on the posterior slope of each valve and by microscopic pin-points on the sides of the valves. Donax striatus Linné also a lower West Indian species is as large, but characterized by a flat to slightly concave posterior slope which bears numer- ous fine radial threads, Donax gouldi Dall Gould’s Donax Plate 31q San Luis Obispo, California, to Mexico. Common form: *4 inch in length, fairly obese, truncate at the posterior end where the beaks are located. Shell glossy, smooth, except for numerous, microscopic, axial threads at the anterior end. Exterior cream to white with variable color rays of light-tan. Margins of valves commonly flushed with purple. Interior stained with purple or bluish brown. Common on beaches, especially in the north. Known locally as the Bean Clam. Small form: 7 inch in length, slightly more obese, without the color rays in most cases. Common, especially in the south. Donax californicus Conrad California Donax Plate 31p Santa Barbara, California, to Panama. Up to 1 inch in length, narrowly pointed at both ends. Shell glossy or oily-smooth with a tan to greenish-tan perlostracum. Interior white or with . SANGUINOLARIIDAE 439 a purple flush, and with a strong splotch of purple at each end of the dorsal margin. Common in shallow waters of bays along the shore. Genus Iphigenia Schumacher 1817 Iphigenia brasiliensis Lamarck Giant False Donax Plate 32u South half of Florida and the West Indies. 2 to 2% inches in length, rather heavy, elongate, roughly diamond- shaped in side view and moderately inflated. Posterior dorsal slope flattish. Exterior smoothish, cream with a purple-stained beak area. Commonly en- tirely covered with a thin, glossy, brown periostracum. Moderately common in shallow water in sand. Family SANGUINOLARIIDAE Genus Sanguinolaria Lamarck 1799 Sanguinolaria cruenta Solander Atlantic Sanguin Plate god South Florida, the Gulf States and the West Indies. 174 to 2 inches in length, moderately compressed, the left valve slightly flatter than the right. With a slight posterior gape. Exterior glossy, smooth, except for minute concentric scratches. Pallial sinus with a U-shaped hump at the top. Color white with the beaks and area below a bright-red which fades ventrally into white. Uncommon in the West Indies, rare in Florida. S. sanguinolenta Gmelin is a later name for this species, Subgenus Nuttallia Dall 1898 Sanguinolaria nuttalli Conrad Nuttall’s Mahogany Clam Plate 29x Monterey, California, to Lower California. 2% to 3% inches in length. A handsome species characterized by its smooth, oval form, glossy nut-brown color, with its right valve almost flat and its left valve inflated. External ligament like a brown leather button. Interior whitish, commoaly with rosy or purplish blush. Common near estu- aries in 6 to 8 inches of mud. Genus Asaphis Modeer 1793 Asaphis deflorata Linné Gaudy Asaphis Plate goa Southeast Florida and the West Indies. 440 American Seashells 2 inches in length, moderately inflated. Sculpture of numerous, coarse, irregularly sized, radial threads. Color variable and brighter on the inside: whitish, yellow, or stained with red, rose or purple. Beaks inflated and rolled in under themselves a little. A moderately common, intertidal species, also known from the Indo-Pacific. Genus Tagelus Gray 1847 Tagelus plebeius Solander Stout Tagelus Plate 30d Cape Cod to south Florida and the Gulf States. 2 to 3% inches in length, oblong, subcylindrical, rather inflated, rounded posteriorly, obliquely truncate anteriorly. Beaks indistinct, close together and nearer the posterior end of the shell. Hinge with 2 small, projecting cardinal teeth, with a large bulbous callus just behind them. Exterior smoothish, with tiny, irregular, concentric scratches. Periostracum moderately thick, shiny, olive-green to brownish yellow. Moderately common in shallow water in mud-sand intertidal areas. T. gibbus Spengler is a later name for this species. Tagelus californianus Conrad Californian Tagelus Plate 29u Monterey, California, to Panama. 2 to 4 inches in length. Pallial sinus does not extend past a line vertical to the beaks. External color yellowish white under a dark-brown periostra- cum which is radially striated. Interior white. Common on muddy sand flats near marshes. Lives 8 to 10 inches below the surface of the sand. Tagelus affinis C. B. Adams Affinis Tagelus Southern California to Panama. 1% to 2% inches in length. Shell thin. Pallial sinus extends to a line slightly beyond the beaks, that is, about 53 to 60 percent of the total length of the shell. Dredged from 3 to 40 fathoms in mud-sand, but commonly washed ashore. Subgenus Mesopleura Conrad 1867 Tagelus divisus Spengler Purplish Tagelus Plate 30g Cape Cod to south Florida, the Gulf States and the Caribbean. 1 to 1% inches in length, elongate, subcylindrical, fragile and smooth. , The valves are reinforced internally by a very weak, radial rib (commonly SANGUINOLARIIDAE 441 obscure) running across the center of the valve just anterior to the 2 small, projecting cardinal teeth. Color of shell whitish purple, covered externally with a very thin, chestnut-brown, glossy periostracum. A common shallow- water species. Tagelus subteres Conrad Purplish Pacific Tagelus Plate 29s Santa Barbara, California, to Lower California. 1 to 2 inches in length, subcylindrical, slightly arcuate with the dorsal margins sloping down from the beaks. Color pale purple inside and out. Periostracum yellowish brown and finely wrinkled. Moderately common in shallow water in sandy mud. Tagelus politus Carpenter from Central America does not slope down from the beaks so strongly, is a thinner shell and much more darkly colored with violet. Genus Heterodonax Morch 1853 Shell less than 1 inch in length, resembling a strong, oval Tellina. Two cardinals and two lateral teeth in each valve, the laterals usually not very distinct. Pallial sinus extends *5 the length of the shell. Heterodonax bimaculatus Linné Small False Donax Plate 30h South half of Florida and the West Indies. Southern California to Panama. ¥ to 1 inch in length, oval, with a truncate anterior end and moderately inflated. Exterior smoothish, with numerous fine growth lines. 2 cardinals in each valve. Anterior to the beaks (which point forward), the hinge is thick for a short distance, then followed by a thinner, concave portion. Color variable: white with 2 oblong crimson spots inside; violet with radial streaks; pink, yellow or mauve; some are speckled with black or brown. This is a common species found with Donax on the slopes of sandy beaches. H. pa- cificus Conrad 1s a synonym. Genus Gari Schumacher 1817 Shell fairly large, elongate-oval, beaks near the center; hinge thick and with 2 small, bifid teeth just under the beak. Alias Psammobia Lam. 1818. Subgenus Psammocola Blainville 1824 Gari californica Conrad Californian Sunset Clam Plate 29n Aleutians to off San Diego, California. Japan. 44? American Seashells 2 to 4 inches in length, elongate-oval, fairly strong; the low beaks are nearer the anterior end. Sculpture of strong, irregular, concentric growth lines. Periostracum brownish gray, fairly thin and irregularly wrinkled. Exterior shell dirty-white or cream, and may have faint, narrow, radial rays of purple. Common offshore to 25 fathoms. Commonly washed ashore after storms, especially between Sea Beach and Huntington Beach, California. The subgenus Gobraeus Leach 1852 is a later name for Psammocola. Suborder ADAPEDONTA Superfamily SOLENACEA Family SOLENIDAE Genus Siligua Muhlfeld 1811 Shell commonly 6 inches in length, oval, compressed laterally; with a rather straight, raised, internal rib ventrally directed. Hinge like Ensis. Siliqua costata Say Atlantic Razor Clam Plate 30f Gulf of St. Lawrence to New Jersey. 2 to 2% inches in length, ovate-elongate, compressed, fragile, smooth and with a shiny, green periostracum. Interior glossy, purplish white, with a strong, white, raised rib running down from the hinge to the middle of the anterior end. Very common on shallow-water sand-flats along the New England coast. Siliqua squama Blainville found offshore from Newfoundland to Cape Cod is larger, thicker, white internally, and its internal, supporting rib slant- ing posteriorly instead of anteriorly as in costata. Uncommon, Siliqua lucida Conrad Transparent Razor Clam Bolinas Bay, California, to Lower California. 1 to 1% inches in length. Very thin, fragile and translucent. Moder- ately elongate. Shell whitish tan, with broad, indistinct, radial rays of darker tan or rosy purplish. Periostracum thin, olive-green and varnish-like. Mod- erately common in sand at low tide to 25 fathoms. This species can be distinguished from the young of S. patula by its narrower and higher internal rib which crosses the shell at right-angles, and in being more arcuate on its ventral margin, Siliqua patula Dixon Pacific Razor Clam Plate z9y Alaska to Monterey, California. SOLENIDAE 443 5 to 6 inches in length, oval-oblong in shape, laterally compressed and moderately thin. Periostracum varnish-like and olive-green. Interior glossy and whitish with a purplish flush. Internal rib under teeth descending ob- liquely toward the anterior end. Animal without dark coloration. The variety nuttalli Conrad is asynonym. Do not confuse with S. alta. An abun- dant, edible species found in mud and sand on ocean beaches. Siliqua alta Dall Dall’s Razor Clam Arctic Ocean to Cook’s Inlet, Alaska. Russia. 4 to 5 inches in length, similar to patwla, but chalky-white inside, more truncate at both ends, a heavier shell, and with a stronger, narrower and vertical (not oblique) rib on the inside. S. media Sowerby from the same region may possibly be the young of this species, although it is blushed with purple inside. S. alta is common and edible. Genus Ensis Schumacher 1817 The Jackknife Clams closely resemble Solen, but the left valve has 2 vertical, cardinal teeth, and each valve has a long, low posterior tooth. Ensis directus Conrad Atlantic Jackknife Clam Plate 30k Labrador to South Carolina. Florida? Up to 10 inches in length, 6 times as long as high, moderately curved and with sharp edges. Shell white, covered with a thin, varnish-like, brown- ish-green periostracum. Common on sand-flats in New England. Edible. Ensis minor Dall from both sides of Florida to Texas rarely exceeds 3 inches in length, is more fragile, relatively longer, and is more pointed at the free end (not the end with the teeth). Internally it has purplish stains. Moderately common between tide marks. Some workers consider this a sub- species of directus. E. megistus Pilsbry and McGinty are probably 5-inch- long specimens of minor. Ensis myrae S. S. Berry Californian Jackknife Clam Southern California. 2 inches in length, with much the same characters as in directus. This is the only Ensis in California and it is not very common. It has been errone- ously called californicus Dall which, however, is a more southerly species. For a new name for the Californian Ensis, consult future works by Pacific Coast students (probably S. S. Berry).’ 1Since appeared Aug. 1953 in Trans. San Diego Soc. Nat. Hist., vol. 11, p. 398. +44 American Seashells Genus Solen Linné 1758 Similar to Ensis, but with only a single tooth at the end of each valve. Solen sicarius Gould Blunt Jackknife Clam Plate 29v British Columbia to Lower California. 2 to 4 inches in length, 4 times as long as wide. Exterior with a varnish- like, olive to greenish periostracum. Moderately common in certain local- ities, especially sandy mud flats. Also dredged in 25 fathoms. Solen viridis Say Green Jackknife Clam Plate 30n Rhode Island to northern Florida and the Gulf States. About 2 inches in length, about 4 times as long as wide; dorsal edge straight, ventral edge curved. Hinge with a single projecting tooth at the very end of the valve. Color white; periostracum thin, varnish-like, light greenish or brownish. Moderately common in shallow-water sand flats. Solen rosaceus Carpenter Rosy Jackknife Clam Santa Barbara, California, to Mazatlan, Mexico. 1 to 3 inches in length, almost 5 times as long as wide. Shell fragile, with a thin, glossy, olive periostracum. Beachworm specimens are whitish with rosy stains inside and out. It is more cylindrical, the anterior extremity 1s more rounded and narrower than in sicarius. An abundant species along the sandy shores of bays. Also to 25 fathoms. Genus Solecurtus Blainville 1825 Quadrate to rectangular in shape; gaping at both ends. With weak, “clapboard” sculpturing. Ligament prominent, external and posterior to the small beaks. Right valve with 2 strong, horizontally jutting cardinal teeth just under the centrally located beaks. Left valve with 1 cardinal. Psam- mosolen Risso 1826 is a synonym. Solecurtus cumingianus Dunker Corrugated Razor Clam North Carolina to south half of Florida to Texas. 1 to 2 inches in length with characters of the genus. Color all white, with a dull, yellowish-gray periostracum. Outer surface sculptured with MACTRIDAE 445 coarse, concentric, irregular lines and with sharp, small, oblique, wavy threads. Uncommon offshore. Solecurtus sanctaemarthae Orbigny St. Martha’s Razor Clam : Plate 301 North Carolina to southeast Florida and the West Indies. ¥% inch in length, differing from cumingianus in being twice as long as high (instead of 2% times) and in having stronger sculpturing. Uncommon from shallow water to 25 fathoms. Superfamily MACTRACEA Family MACTRIDAE Key to Some Genera of Mactridae a. Ligament entirely internal op 2 Loe eee einiinia aa. Ligament partially external b. Chondrophore set off from ligament by a thin shelly plate: c. Posterior rostrate; shell thin and fragile . . . .~ Labiosa ec. Both ends rounded; shellthick . . . . . . . . Mactra bb: Chondrophore not set off bya plate’ 9 5. 8 5 Spisula Figure 89. Hinge of the Atlantic Fragile Mactra, Mactra fragilis Gmelin, 2 inches. Genus Mactra Linné 1767 Mactra fragilis Gmelin Fragile Atlantic Mactra Plate 32s; figure 89 North Carolina to Florida, Texas and the West Indies. 2 to 2% inches in length, oval, moderately thin, but strong, and smooth- ish. Posterior slope with 2 radial, small ridges, one of which is very close to the dorsal margin of the valve. With a fairly large posterior gape. Color cream-white, with a thin, silky, grayish periostracum. Moderately common in shallow water. Rarely reaches 4 inches in length. Mactra californica Conrad Californian Mactra Figure god Neeah Bay, Washington, to Panama. 446 American Seashells Up to 1% inches in length, moderately fragile, moderately elongate and with the beaks central. Characterized by peculiar, concentric undulations on the beaks. This small species of Mactra is common in lagoons and bays of southern California. It lives 3 to 6 inches below the surface of the sand. Mactra nasuta Gould Gould’s Pacific Mactra San Pedro, California, to Mazatlan, Mexico. Up to 3% inches in length, similar to californica, but more oval at the ventral margin, without concentric undulations on the beaks, and with 2 very distinct, raised, radial ridges on the posterior dorsal margin. The whitish shell is glossy and the periostracum is shiny and yellowish tan. Not very common. Genus Spisula Gray 1837 Spisula solidissima Dillwyn Atlantic Surf Clam Plate 32p Nova Scotia to South Carolina. Up to 7 inches in length (usually about 4 or 5 inches), strong, oval and smoothish, except for small, irregular growth lines. The lateral teeth bear very tiny, saw-tooth ridges. Color yellowish white with a thin yellowish brown periostracum. Common below low-water mark on ocean beaches. After violent winter storms, these clams are cast ashore in incredible num- bers, some estimates giving an approximate count of 50 million clams along a ten-mile stretch. The subspecies similis Say (Cape Cod to both sides of Florida and to Texas) is more elongate, its anterior slope flatter, and its pallial sinus longer and not sloping slightly upward. In the left valve, the tiny double tooth, just anterior to the spoon-shaped chondrophore, 1s usually much larger and stronger. Moderately common, and commonly existing with the typical spe- cies in the northern part of its range. Compare with polynyma which has a larger pallial sinus. Spisula polynyma Stimpson Stimpson’s Surf Clam Plate 31w; figure 26k Arctic Seas to Rhode Island. Arctic Seas to Puget Sound. Also Japan. 3 to 5 inches in length, beaks very near the middle of the valve. Anterior MACTRIDAE 4.47 end smaller than the elliptical posterior end. Shell chalky, dirty-white and with a coarse, varnish-like, yellowish brown periostracum. Worn shells have coarse, concentric, wide growth lines. The pallial sinus is larger in this spe- cies than in solidissima. Moderately common from low-tide line to 60 fath- oms. The form alaskana Dall is probably a synonym. The fossil, S. voyi Gabb 1868 from the Miocene or Pliocene is possibly only a subspecies. Spisula falcata Gould Hooked Surf Clam Puget Sound, Washington, to California. 2 to 3 inches in length, rather elongate at the narrower anterior end. Exterior chalky with a partially worn-off, light-brown, shiny periostracum. Anterior upper margin of shell slightly concave. Moderately common in sand below low-water line. Figure go. Pacific Surf Clams. a, Spiszla dolabriformis Conrad, 3 inches; b, S. hemphilli Dall, 6 inches; ec, Spisula catilliformis Conrad, 4 inches; d, Mactra californica Conrad, 1% inches; e, S. planulata Conrad, 2 inches. 448 American Seashells Spisula planulata Conrad Flattish Surf Clam Figure goe Monterey, California, to Lower California. 1 to 2 inches in length, 7 as high. Beaks almost at the middle. Anterior upper margin of the shell sharp-edged and straight. Exterior smooth, yellow- ish, shiny with the edges commonly stained with rusty-brown. Not very common. Found from low-water line to 36 fathoms. Spisula catilliformis Conrad Catilliform Surf Clam Figure goc Washington State to Ensenada, California. 4 to 5 inches in.length, almost as high as long. An oval shell with the beaks slightly nearer the anterior end. Moderately obese. Dull-ivory, com- monly stained with reddish brown. With numerous, irregularly sized and spaced growth lines. Periostracum glossy, thin and usually worn off. Pallial sinus deep, running anteriorly as far back as the middle of the shell. Rather uncommonly washed ashore. Live specimens rare. Spisula dolabriformis Conrad Hatchet Surf Clam Figure goa Lobitas, California, to Mexico. 3 to 4 inches in length, rather elongate, compressed and smooth. Poste- rior end shorter, but more expansive than the rather drawn-out anterior end. Right valve with the posterior lateral tooth separated into 2 teeth lengthwise by a long, deep channel. Color a smooth, ivory white, with a dull, light-tan, thin periostracum. Small gape at the posterior end. Do not confuse with Mactra nasuta which dips down at the ventral margin, has a shiny periostra- cum and a wide posterior gape, nor with Spisula falcata which is similar in shape, but chalky and with very convex ventral margin to the hinge just below the chondrophore. Moderately common. Spisula hemphilli Dall Hemphill’s Surf Clam Figure gob San Pedro, California, to Central America. Up to 6 inches in length, about %4 as high. Rather obese. Posterior end more obese and shorter than the downwardly swept, compressed anterior end. Periostracum grayish brown, dull, coarsely and concentrically wrinkled. The pallial sinus is moderately deep and inclined upward. Fairly common along the southern beaches of California. MACTRIDAE 449 Genus Mulima Gray 1837 Mulinia lateralis Say Dwarf Surf Clam Plate 32-0 Maine to north Florida and to Texas. ¥s to % inch in length, resembling a young Spiswla or Mactra, moder- ately obese, beaks quite prominent and near the center of the shell and point- ing toward each other. Exterior whitish to cream and smoothish, except for a fairly distinct, radial ridge near the posterior end. Concentric lines plainly seen in the thin, yellowish periostracum. Distinguished from young Spisula solidissma which have a proportionately much larger chondrophore in the hinge and which have tiny, saw-tooth denticles on the lower anterior and lateral hinge-teeth. A very abundant species in warm, shallow water in sand. Genus Labiosa Moller 1832 Posterior slightly gaping. Shell fragile. Hinge with a prominent chon- drophore. Cardinal teeth small and close to the chondrophore. Ligament submerged, except at the anterior end, and separated from the chondrophore by a shelly plate. Raeta Gray 1853 1s the same. This is also Anatina Schu- macher 1817, not Bosc 1816. Labiosa plicatella Lamarck Channeled Duck Clam Plate 32q North Carolina to Florida, Texas and the West Indies. 2 to 3 inches in length, % as high, egg-shell thin, but moderately strong. Concentric sculpture of smoothish, distinct ribs which on the inside of the valves show as grooves. Radial sculpture of very fine, crinkly threads. Color pure white. Formerly known as Raeta canaliculata Say. R. campechensis Gray is also a synonym. Commonly washed ashore, especially along the strands of the Carolinas, but rarely seen alive. Labiosa lineata Say Smooth Duck Clam North Carolina to the north 74 of Florida and to Texas. 2 to 3 inches in length, 4 as high, fairly thin but strong. White to tan in color. Moderately smooth, except for irregular growth lines and tiny, but distinct, concentric ribs near the beaks. Posterior end with a distinct radial rib behind which the shell gapes with flaring edges. Uncommon in most areas of its range. 450 American Seashells Genus Schizothaerus Conrad 1853 Shell large with a roundish posterior gape. Hinge with small cardinal teeth; lateral teeth very small and close to the cardinals. Ligament external and separated from the cartilage pit by a shelly plate. Schizothaerus nuttalli nuttalli Conrad Pacific Gaper Plate: 31z Washington to Lower California. Up to 8 inches in length. An oblongish to oval, strong, smoothish shell with a prominent gape at the posterior end. The neat, well-formed beaks are located %4 to % from the anterior end. The pallial sinus is very large and deep. Periostracum grayish. Common. Compare with the northern sub- species capax Conrad. Schizothaerus nuttalli capax Gould Alaskan Gaper Kodiak Island, Alaska, to Monterey, California. Up to ro inches in length, differing from the typical muttalli in being much more oval, more obese, and dipping downward into a well-rounded, ventral margin. This species is very common on most sandy and mud beaches in Puget Sound. Genus Rangia Desmoulins 1832 Rangia cuneata Gray Common Rangia Figure gra, b Northwest Florida to Texas. 1 to 2% inches in length, obliquely ovate, very thick and heavy. The beaks which are near the oval, anterior end are high, inrolled and pointing downward and anteriorly. Exterior whitish, but covered with a strong, smoothish, gray-brown periostracum. Interior glossy, white and with a blue- gray tinge. Pallial sinus small, but moderately deep and distinct. A common fresh-water to brackish-water species found in coastal areas. R. masuta Dall is probably only a rostrate form of this species. Compare with R. flexuosa. Subgenus Rangianella Conrad 1867 Rangia flexuosa Conrad Brown Rangia Figure gic, d Louisiana to Texas and Vera Cruz, Mexico. 1 to 1% inches in length, resembling an elongate cuneata, but with no MESODESMATIDAE 451 Figure 91. Rangia Marsh Clams of the Atlantic Gulf States. a and b, Rangia cuneata Gray, 2 inches; ¢ and d, R. flexuosa Conrad, 1% inches. distinct pallial sinus, with much shorter laterals, with a faintly impressed, large lunule, and colored light-brown inside. A rare and elusive species from marsh areas. R. rostrata Petit is a synonym. Family MESODESMATIDAE Genus Mesodesma Deshayes 1830 Like a large Donax with a prominent chondrophore. Laterals with fine denticles. Mesodesma arctatum Conrad Arctic Wedge Clam Plate 32r Greenland to Chesapeake Bay. About 1% inches in length, somewhat shaped like a Donax, fairly thick and compressed. Chondrophore fairly large and spoon-shaped. Left valve with a long anterior and posterior lateral tooth, both of which have fine, comb-like teeth on each side. Pallial sinus small and U-shaped. Interior tan to cream. Exterior with a thin, yellowish, smooth periostracum. Common from low water to 50 fathoms. 452 American Seashells Genus FErvilia Turton 1822 Shell small, concentrically striate, and sometimes brightly hued. Liga- ment absent; resilrum small and internal. Laterals small. Left cardinal large and bifid or split. Ervilia concentrica Gould Concentric Ervilia North Carolina to both sides of Florida and the West Indies. %46 of an inch in length, %% as high, elliptical in outline, moderately com- pressed, although some are somewhat inflated. Each end is rounded to the same degree, and the beaks are central. There is a pinpoint depression just behind the glossy, inrolled beaks. Sculpture of fine, numerous concentric ridges. Radial threads may be present to form tiny beads. Color white, yellow or commonly with a pink blush. Common just offshore to 50 fathoms. E. rostratula Rehder from Lake Worth, Florida, is similar, but the posterior end is slightly more pointed. Family HIATELLIDAE Genus Hiatella Daudin 1801 Shell irregular due to nestling and burrowing habits. Texture chalky. No definite teeth in the thickened hinge of the adults. Pallial line discon- tinuous; siphons naked and slightly separated at the tips. Saxicava Fleuriau 1802 is the same. Hiatella arctica Linné Arctic Saxicave Figure 92a Arctic Seas to deep water in the West Indies. Arctic Seas to deep water off Panama. PRODISSOCONCH Figure 92. The young shells of Hiatella reared under the same artificial conditions. a, Hiatella arctica Linné; b, H. striata Fleuriau. (After M. Lebour 1938.) Generally 1 inch in length, but rarely 2 to 3 inches. A very variable species in its shape. The young are rather evenly oblong, but the adults become oblong, oval or twisted and misshapen. The shell is elongate with FVATERLIDAE 453 the dorsal and ventral margins usually parallel to each other. A posterior gape may be present. Beaks close together, about % back from the anterior end. Just behind them is a conspicuous, bean-shaped, external ligament. Shell chalky, white and with coarse, irregular growth lines. Periostracum gray, thin and usually flakes off in dried specimens. With a weak or fairly strong radial rib at the posterior end. The rib may be scaled. Common in cold water. This is H. rugosa Linné and pholadis Linné. -Hiatella striata Fleuriau (H. gallicana Lamarck and rugosa of some authors) is almost indistinguishable in the adult form from arctica. The young, however, in striata do not have the two radial spinose ribs. This species breeds in winter, while arctica breeds in summer. The eggs are pinkish cream, while those of arctica are red. It nearly always bores into stone. Genus Cyrtodaria Daudin 1799 Cyrtodaria siliqua Spengler Northern Propeller Clam Labrador to Rhode Island. 2 to 3 inches in length, about % as high. Gapes at both ends, but more so posteriorly where the large siphonal snout projects out about an inch. Beaks hardly noticeable, placed slightly toward the anterior end. The strong, wide ligament is external at the very anterior end of the dorsal mar- gin. Shell chalky, white with a bluish tint. The valves are thick-shelled, with a coarse callus inside. The valves are slightly twisted in propeller fashion. Hinge a simple bar with a fairly large bulbous swelling under the ligament. In life, the periostracum is light-brown, glossy, smooth and covers the en- tire exterior. Dried valves soon lose the flaky, blackened periostracum. Moderately common offshore down to go fathoms. On occasion, found in fish stomachs. A similar species, Cyrtodaria kurriana Dunker, is found in arctic waters along the shores at low tide. It is 3 times as long as high, hardly twisted and rarely exceeds 1% inches in length. Uncommon in collections. Genus Panomya Gray 1857 Panomya arctica Lamarck Arctic Rough Mya Arctic Seas to Chesapeake Bay. 2 to 3 inches in length, about % as high, squarish in outline. Looks somewhat like a misshapen Mya, but lacks teeth and a chondrophore in the hinge, and has a coarse, flaky, light-brown periostracum. Characterized by oblong or oval, sunk-in muscle and pallial line scars. There are 2 poorly de- 454 American Seashells fined radial ridges near the center of the valves. Common in mud in cold waters offshore. Panomya ampla Dall Ample Rough Mya Aleutian Islands to Puget Sound, Washington. 2 to 3 inches in length. A peculiarly distorted, heavy shell which is much gaping at both ends. Anterior end crudely pointed; posterior broadly truncate. With 3 to 6 depressed scars on the white interior. Exterior con- centrically roughened, ash-white in color, with a border of thick, irregular, black periostracum. Hinge without definite teeth. Uncommon offshore in cold water. Genus Panope Menard 1807 Panope generosa Gould Geoduck (Goo-ee-duck) Alaska to the Gulf of California. 7 to 9 inches in length. Inflated, slightly elongate and rather thick- shelled. Gaping at both ends. Coarse, concentric, wavy sculpture present, especially noticeable near the small, central, depressed beaks. Periostracum thin and yellowish. Exterior of shell dirty-white to cream; interior semi- glossy and white. Hinge with a single, large, horizontal thickening. The 2 long, united siphons of the animal are half the weight of the entire clam. Common in mud 2 or 3 feet deep in the northwestern states. Edible but tough. Freaks have been named solida Dall, globosa Dall and taeniata Dall. For an interesting and well-illustrated account of this species, see Natural History Magazine (N.Y.), April, 1948, on “We Go Gooeyducking” by the Milnes. Panope bitruncata Conrad from North Carolina to Florida is 5 to 6 inches in length and resembles the Pacific geoduck. Dead valves are rarely found, and IJ have never seen a live specimen. Possibly extinct. Superfamily MY ACEA Family MY ACIDAE Genus Mya Linné 1758 These are the soft-shell or “steamer” clams which are so popular in New England. The valves are slightly unequal in size and have a large posterior gape. Resilium internal, placed posterior to the beaks and attached in the left valve to a horizontally projecting chondrophore. MY ACIDAE zine) Mya arenaria Linné Soft-shell Clam Plate 32x Labrador to off North Carolina. Introduced to western United States. 1 to 6 inches in length. Pallial sinus somewhat V-shaped in contrast to U-shaped in truncata. Shell elliptical. Periostracum very thin and light- gray to straw. Chondrophore in left valve long, spoon-shaped and shallow. M. japonica Jay of the Pacific coast is probably this speices. This common, delectable clam, also known as the long-necked clam, steamer and nanny nose, is harvested from the readily accessible mud flats of New England in great numbers. In 1935, nearly 12 million pounds, valued at $704,000, were taken from our eastern shores. A hundred pounds of clams furnishes 35 pounds of meat, while the equivalent weight of oysters would give only 13 pounds. Mya truncata Linné Truncate Soft-shell Clam Plate 32v Arctic Seas to Nahant, Massachusetts. Europe. Arctic Seas to Port Orchard, Washington. Japan. 1 to 3 inches in length, similar to arenaria, but widely gaping at its abruptly truncate, posterior end. The pallial sinus is U-shaped. In Green- land and Iceland this species is fairly common and 1s considered a delicacy. It is also a food for the walrus, king eider duck, arctic fox and the codfish. It is uncommon in American collections. Genus Sphenia Turton 1822 Shell small and fragile; surface with concentric ridges; hinge-teeth ab- sent. The elongate, flattened chondrophore in the left valve juts obliquely under the hinge margin of the right valve. These clams are nestlers, and are consequently irregular in shape in many instances. Sphenia fragilis Carpenter Fragile Sphenia Oregon to Mazatlan, Mexico. %4 inch in length, quite elongate, with a long, narrow, compressed, posterior snout. Anterior half obese and rotund. Beaks fat and close to- gether. Shell fragile, chalky, white and with fine, concentric threads. Peri- ostracum yellowish gray, dull and usually worn off the beak area. Chon- drophore in left valve large and with 2 lobes. Socket in right valve large and round. The posterior snout is commonly twisted. Low tide to 46 fathoms in mud. Common. 456 American Seashells Sphenia ovoidea Carpenter (Alaska to Panama) is half as large, smoother, and more ovoid in outline without the prominent snout. Uncommon. Genus Cryptomya Conrad 1849 Somewhat like a small, fragile Mya, but more fragile, and the night valve is larger and more obese than the left. Large chondrophore in the left valve is thin, flat-topped with an anterior ridge. Posterior gape and pallial sinus almost absent. Siphons very short. Cryptomya californica Conrad Californian Glass Mya Alaska to central Mexico. 1 to 1% inches in length, oval, fragile, moderately obese. Right valve fatter. Right beak crowds slightly over the left beak. Posterior gape very small. Chondrophore in left valve large, tucks against a small, concave shelf under the right beak. Exterior chalky and with small growth lines. Peri- ostracum dull-gray, faintly and radially striped at the posterior end. Interior slightly nacreous in fresh specimens. Common in sand where it may live as deep as 20 inches. The short siphons enter the burrows of other marine animals, Genus Platyodon Conrad 1837 Shell somewhat resembling a very fat Mya, with a fairly thick shell, rugose sculpturing and fairly small chondrophore. Platyodon cancellatus Conrad Chubby Mya Queen Charlotte Island, B.C., to San Diego, California. 2 to 3 inches in length, rounded rectangular and obese. Gaping widely posteriorly. Shell strong, rather thick and with fine, clapboard-like, concen- tric growth lines. Rarely with very weak radial grooves. Chondrophore in left valve quite thick and arched. Beak of right valve crowds under beak of left valve. Shell chalky and white; periostracum thin, yellowish brown to rusty, and rugose posteriorly. Moderately common near beds of pholads. Lives in sand. Family CORBULIDAE Genus Varicorbula Grant and Gale 1931 Varicorbula operculata Philippi 1848 Oval Corbula North Carolina to the Gulf of Mexico and the West Indies. CORBULIDAE 59) ¥8 of an inch in length, %4 as high, moderately thin-shelled and glossy. Beaks high, curled under and pointing anteriorly. Right valve subtrigonal in shape, very obese and with strong, concentric ridges. Left valve more elongate, smaller, less obese and with numerous but weaker ridges. Color white, but some may be tinted with rose near the margins. Uncommonly dredged from 12 to 250 fathoms. Live specimens very rare. This is C. dis- parilis of authors. Genus Corbula Bruguicre 1792 Small, thick shells characterized by one valve (commonly the right) being larger than the other. Posterior end commonly rostrate. Resilium and ligament internal. The genus Aloidis Miihlfeld was in current use until recently. Corbula contracta Say Contracted Corbula Cape Cod to Florida and the West Indies. % inch in length, oblong, moderately to strongly obese. Both valves about the same size, except that the posterior, ventral margin of the right valve overlaps that of the left. The numerous, poorly defined, concentric ridges on the outside of the valves extend over the posterior, radial ridge on to the posterior slope. The left valve has a V-shaped notch in the hinge just anterior to the beak. Color dirty-gray. A common shallow-water species. Corbula dietziana C. B. Adams Dietz’s Corbula North Carolina to southeast Florida and the West Indies. % to % inch in length, like contracta, but larger, thicker-shelled and pinkish inside. The ventral margins are blushed or rayed with carmine-rose. Microscopic threads numerous between the few coarse, concentric ridges. Compare with the smaller and more compressed barrattiana. Commonly dredged offshore in the Miami region. Corbula nasuta Say Snub-nose Corbula North Carolina to both sides of Florida and the West Indies. %416 to % inch in length, oblong, obese and strongly rostrate at the pos- terior end. The posterior end looks as if it had been severely pinched. Right valve considerably larger than the left. Margins of valves with a thick border 458 American Seashells of dark-brown perlostracum. Concentric sculpture of distinct ridges. Color yellowish to brownish white. Uncommon in shallow water. Corbula barrattiana C. B. Adams Barratt’s Corbula Figure 93a North Carolina to both sides of Florida and the West Indies. ¥, inch in length, moderately compressed, rostrate at the posterior end, with poorly developed or without concentric ridges in the beak area. Right valve slightly larger than the left. The posterior end of the rostrum in the right valve projects far beyond that of the left valve. Color variable: white, pink, mauve, yellow, orange or reddish. Uncommon in shallow water to 50 fathoms. FigurE 93. Corbula clams. a, Corbula barrattiana C. B. Adams, %4 inch (Atlantic Coast); b, Corbula swiftiana C. B. Adams, 14 inch (Atlantic Coast). Three views of each Corbula swiftiana C. B. Adams Swift’s Corbula Figure 93b Massachusetts to east Florida and the West Indies. % inch in length, oblong, moderately obese; right valve larger, more obese and overlapping the left valve at the ventral posterior region. Posterior slope in the right valve bounded by 2 radial ridges, one of which is close to the margin of the valve. The left valve has only 1 ridge. Shell thick, with the posterior muscle scar on a slightly raised platform. External sculpture the same on each valve, consisting of irregular, concentric ridges. Color GASG@ROCHAENIDAE 459 dull white with a thin yellowish periostracum. Moderately common from 6 to 100 fathoms. Corbula luteola Carpenter Common Western Corbula Monterey, California, to Panama. ¥ inch in length, slightly obese, with the right valve more obese and overlapping the left valve on the ventral margin. Anterior end elliptical in outline; posterior end coming to a blunt point. Beaks strong, close to- gether and slightly nearer the posterior end. Shell porcellaneous, whitish gray and may be flushed with pinkish or purplish. Interior whitish, but commonly yellowish with purple-red staining. Sculpture of weak, concen- tric growth lines which are less noticeable toward the smoothish beaks. Common in some localities in sand and rocky, rubbly beaches to 25 fathoms. C. rosea Williamson is merely a pink color phase of this species. Corbula porcella Dall Ribbed Western Corbula Santa Rosa Island, California, to Panama. ¥% to ¥% inch in length, similar to Juteola, but much fatter, chalky, gray, and with much stronger concentric riblets. The right valve overlaps the left valve very prominently on the ventral margin. Moderately common from shallow water to 53 fathoms. Family GASTROCHAENIDAE Genus ROCELLARIA Blainville 1828 Both valves fairly thin, somewhat chalky in substance, and equal in size and shape. The anterior gape Is very large. Beaks very near the anterior end. Hinge-teeth obscure. These clams form flask-shaped excavations in the rocks which they line with calcareous material. When not protected by a burrow, they form a shelly tube to which debris is attached. Gastrochaena Spengler is another genus from the Indo-Pacific area (formerly Fistwlana Brug., not Miller). Rocellaria hians Gmelin Atlantic Rocellaria North Carolina to Texas and the West Indies. ¥% to % inch in length; valves rather spathate, with low, indistinct, fine, concentric ridges. Posterior end large and rounded. The entire anterior- ventral end is widely open to accommodate the foot. Color white. Common 460 American Seashells in soft coral rocks. Erroneously called cuneiformis Spengler which is an Indo-Pacific species (see E. Lamy, 1924). Rocellaria ovata Sowerby (Bermuda and the Atlantic Coast, rare) is very similar, but the beaks are at the very end of the valve, and the shell is more elongate. In hians, there is a very small, wing-like projection of the valve in front of the beak. Genus Spengleria Tryon 1861 Similar to Rocellaria, but truncate at the posterior end where there are strong, concentric ribs. Beaks at the anterior third of the shell. Spengleria rostrata Spengler Atlantic Spengler Clam Southeast Florida and the West Indies. 1 inch in length; valve truncate at the posterior end. There is a very characteristic, elevated, triangular area which radiates from the beaks to the large, posterior end. This area is crossed by strong, transverse lamellations resembling a washboard. Commonly found boring in soft coral rock. Un- common in Florida. Superfamily ADESMACEA Family PHOLADIDAE Pending publication of the extensive researches on this group by Dr. Ruth D. Turner at Harvard University, we are dividing the groups in this family and treating the species in the conventional manner. Genus Cyrtopleura Tryon 1862 Barnea costata Linné Angel Wing Figure 94a Massachusetts to Florida, Texas and the West Indies. 4 to 8 inches in length, moderately fragile; pure white in color, but in life covered by a thin, gray periostracum. With about 30 well-developed, beaded radial ribs which are scale-like at the anterior end of the valve. In fresh material, there is a shelly accessory plate over the hinge area. It is somewhat triangular and with complicated furrows. The internal brace under the beaks is spoon-shaped and with a narrow, strongly hooked at- tached end. Common in sticky mud about a foot under the surface (con- sult “Diggin’ "Em Out” by B. R. Bales, The Nautilus, vol. 59, pp. 13 to 17). Some colonies have shells which have pink, concentric stains on the inside of PHOLADIDAE 461 the valves. No scientific study has been made of this variant, but it may be due to environmental or dietetic conditions. Figure 94. Mud, peat and rock borers of the Atlantic Coast. a, Angel Wing, Barnea costata Linné; b, Petricola pholadiformis Lamarck, False Angel Wing (p. 420); e, Northern Piddock, Zirfaea crispata Linné. All slightly reduced. (From Gould and Binney 1870.) Barnea truncata Say Fallen Angel Wing Massachusetts Bay to south Florida. 2 to 2% inches in length, somewhat resembling the Angel Wing, B. costata, but widely gaping at both ends, truncate at the posterior end, smoothish at the posterior half, and with an elongate, narrow accessory plate over the beak area. Shell fragile, white to grayish white. The internal condyle is long and about the thickness of a toothpick. The siphons are encased in a large, rough, gray, tubular sheath which may be extended 2 to 3 times the length of the shell. Bores into clay, soft rock or wood. Common in intertidal zones. Do not confuse with Zirfaea crispata which is much more squat and has a radial, indented line dividing each valve into 2 areas. Barnea subtruncata Sowerby 1834 Pacific Mud Piddock San Francisco, California, to Lower California. 462 American Seashells 2 to 2% inches in length, very elongate, moderately gaping at the bluntly rounded, posterior end, and widely gaping at the foot end. Top margin of shell folded back on itself at, and just anterior to, the beaks. No distinct radial groove on the sides of the valves. Sculpture at anterior end is of prickly, concentric lamellae which fade out toward the smoothish posterior third. Siphon covered with a heavy, brown periostracum. May be dug out of very soft shale at very low tides in a few localities. Moderately common. Miss Turner advises me that this species must take the earlier name of Barnea spathulata Deshayes. It was formerly known as B. pacifica Stearns. Genus Zirfaea Gray 1842 Zirfaea crispata Linné Great Piddock Figure 94c Newfoundland to New Jersey. Europe. 1 to 2 inches in length, about half as high. Gaping at both ends. Charac- terized by the radial, indented line which divides the valves into 2 areas: the posterior section which has coarse, irregular growth lines, and the anterior section which has fimbriated or scaled growth lines and a serrated edge. Moderately common in cold water where it burrows into soft rgck. This is the only member of the genus on the Atlantic Coast. Zirfaea pilsbryi Lowe Pacific Rough Piddock Bering Sea to San Diego, California. 2 to 4 inches in length, gaping at both ends. Purportedly there are no accessory plates present, except for a small mesoplax. The folded-back dorsal margin at, and in front of, the beaks is covered with a thin, periostracal membrane in fresh material. The yellowish periostracum at the posterior end (siphonal end) is thin, but is not leaf-like as in Parapholas. No eggshell- like material over the anterior foot gape. This species appears in old books as gabbi Tryon. Dead specimens are commonly washed ashore. Siphon studded with tiny, rounded flecks of chitinous material. Genus Pholas Linné 1758 Pholas campechiensis Gmelin Campeche Angel Wing ; Plate 32t North Carolina to the Gulf States and Central America. 3 to 4 inches in length, % as high, fragile, pure-white and closely re- sembling the False Angel Wing, Petricola pholadiformis, but lacking a toothed hinge and ligament, and having a glossy plate rolled over the beaks PHOLADIDAE 463 which is supported by about a dozen, vertical, shelly plates. Not very com- mon. Genus Xylophaga Turton 1822 Xylophaga washingtona Bartsch Washington Wood-eater Washington and Oregon. ¥% inch in length, globular and fragile. The large anterior gape has % of its area covered by a triangular callum in each upper and outer corner. Middle of inside of each valve reinforced by a small, strong, radial cord which is welded to the valve. Color yellowish white. Bores into pieces of water- logged wood. Uncommonly collected in dredging hauls. The Atlantic species X. dorsalis Turton has much the same characters as the above species. It occurs from 100 to 300 fathoms from the Arctic Seas to off Cape Cod. Genus Penitella Valenciennes 1846 Penitella penita Conrad Flap-tipped Piddock Bering Sea to San Diego, California. 1% to 3 inches in length, elongate to moderately short, rotund anteriorly, becoming compressed and narrow posteriorly where there 1s a leathery pro- longation protecting the siphons. Anterior gape commonly closed by an eggshell-like, globose, callus plate which continues up on to the beak region in the form of a pair of rather large plates. Just in back of these there is a short, triangular plate or protoplax set on top of the middle of the dorsal region. Otherwise somewhat resembling the large Parapholas californica. Commonly found boring in rocks and shale. The form sagitta “Stearns” Dall lacks the calcareous covering over the foot gape. It is found with the typical form. Genus Pholadidea Turton 1819 Pholadidea ovoidea Gould Wart-necked Piddock Bering Sea to the Gulf of California. 2 to 3 inches in length, very similar to pilsbryi, but oval in side view. About half of the anterior foot gape is covered by eggshell-like, smoothish calcareous material. It is not impossible that pilsbryi is an ecological form of this species. More studies in their natural history are needed. Moderately 464 American Seashells common. John Q. Burch reports that the siphons have characteristic tubercles on their surface. Siphon cream, covered with a brownish periostracum at the base, the remainder studded with small bars of chitinous material, thus giving a warty appearance. Genus Nettastomella Carpenter 1865 Nettastomella rostrata Valenciennes Rostrate Piddock Puget Sound to San Diego, California. %4 inch in length, with a very large, oval gape posteriorly, and anteriorly with a long, pointed, smooth rostrum or snout which bends downward. Shell proper with widely spaced, delicate, high, concentric lamellae. With- out accessory plates and apophyses. Found by breaking stones apart. Mod- erately common. Genus Parapholas Conrad 1849 Parapholas californica Conrad Scale-sided Piddock Southern California. 3 to 5 inches in length, oval-oblong, rotund, especially anteriorly. Pos- terior round in cross-section and gaping. Dorsal margin with 2 long, com- plicated, accessory plates. Ventral edge covered by one elongate plate. Anterior gape closed over by 2 thin, eggshell-like extensions. Sides of snout with foliated periostracum. Shell proper with a long, radial groove pushing in at the middle. Color grayish white. Interior with 2 long, descending, shelly rods under the middle of the hinge. Common. Genus Navea Gray 1851 Navea subglobosa Gray Abalone Borer San Pedro to Monterey, California. 1% to 34 inch in size. Very obese and subglobular. Anterior end widely gaping with the thick edge of the valves coarsely denticulate. Commonly found boring in abalone shells (Haliotis). Genus Martesia Blainville 1824 Martesia striata Linné Striate Martesia Plate 32w West Florida to Texas and the West Indies. TEREDINIDAE 465 %4 to 1% inches in length, elongate, moderately fragile, gaping at the posterior end and whitish in color. There is a faint radial groove from beak to ventral margin in each valve. Posterior to this groove, the shell is weakly sculptured with concentric growth lines. Anterior to the groove, there are crowded, finely denticulated riblets. Dorsal margins of valve joined by a long, narrow, fragile plate. Over the umbones there 1s a broadly rounded, somewhat heart-shaped, thick, calcareous plate. Anterior gape closed over by an egg-shell callus. Commonly found boring in wood. Martesia cunetformis Say Wedge-shaped Martesia North Carolina to Florida, Texas and the West Indies. % to %4 inch in length, similar to striata, but smaller, chubbier, and with a somewhat triangular or lanceolate accessory plate which commonly has a crease running down the center. ‘There is no free flange extending over the beak. Very commonly found burrowing in wood. Martesia smuthi Tryon Smith’s Martesia New York to north half of Florida and to Texas. % to % inch in length. Bores into rocks and old shells. Very chubby, with a narrow, pointed posterior end. The shelly plate over the beaks is somewhat diamond-shaped, with a pointed anterior end and with no crease on the upper surface. Posterior half of the valves with fine, silken, concentric threads of periostracum. Fairly common in old oyster shells. Family TEREDINIDAE Genus Bankia Gray 1842 This is a genus of shipworms which is very common in warm American waters and which is of great economic importance. The two highly spe- cialized valves of the clam are very similar to those in Teredo, and cannot be used as reliable identification characters. The two plume-like pallets at the posterior end of the worm-like animal which can close off the end of the burrow are used to distinguish species. In adult specimens, the shell at the anterior end which scrapes away the moist wood in the tunnel is about “40 the total length of the animal. The mantel secretes a thin, smooth cal- careous lining for the burrow as an added protection to the soft body. A much fuller and technical account of this group is given by Clench and Turner in Johnsonia (1946). The life history is explained in detail by Sigerfoos (1908). We have included all three known species in eastern American waters, although five others are found in the West Indies. 466 American Seashells Pallets and shells are generally preserved in one part glycerin to tour parts alcohol (70% grain) to permit later study of the delicate cones in the pallets. Permanent slides can be made by soaking the pallets in 90% alcohol for 12 hours, then placing on a slide, covering with a few drops of diaphane or euparol, and adding a long slip-cover. Subgenus Bankiella Bartsch 1921 Bankia gouldi Bartsch Gould’s Shipworm Figures 16; 95d New Jersey to Florida, Texas and the West Indies. Pallets about % inch in length. Cones deep-cupped, with smooth, drawn- out edges. Cones not very crowded at the distal end. Do not confuse with B. caribbea. Gould’s Shipworm is the most widespread and abundant species in this genus on the Atlantic Coast, and hence is the most destructive. It has been found on the Pacific side of the Panama Canal. It is believed that B. mexicana Bartsch is the same species. VENTRAL CONDYLE Figure 95. Atlantic Bankia Shipworms. a, entire animal; b, a pallet; c, interior view of one of the shell valves; d, Bankia gouldi Bartsch; e, B. caribbea Clench and Turner; f, Bankia fimbriatula Moll and Roch. (From Clench and Turner 1946 in Johnsonia.) Subgenus Bankiopsis Clench and Turner 1946 Bankia caribbea Clench and Turner Caribbean Shipworm Figure 95e North Carolina to the Caribbean. TEREDINIDAE 467 Pallets about % inch in length. Cones shallow-cupped, with smooth, not drawn-out edges. Cones very crowded at the distal end. Do not con- fuse with B. gouldi which is more abundant and a larger species. Uncommon. Subgenus Plumulella Clench and Turner 1946 Bankia fimbriatula Moll and Roch Fimbriated Shipworm Figure sf South half of Florida and the West Indies. Pallets % to 1 inch in length. Cones deeply cupped, with beautiful, comb-like serrations on the edges. It has been found on the Pacific side of the Panama Canal, and those specimens were named Bankia canalis Bartsch. Genus Teredo Linné 1758 Similar to Bankia, but the pallet is made up of a single, paddle-shaped piece. Teredo navalis Linné Common Shipworm Both coasts of the United States. Europe and Africa. Shell like that in Bankia and subject to many minute variations. Each of the 2 calcareous pallets is spathate and compressed, but typically sym- metrical. The leathery blade is urn-shaped, widening regularly from a stalk of medium length, then tapering somewhat toward the tip, which 1s decidedly excavated. The base of the blade is calcareous, but approximately the distal third is normally covered by a yellowish or brownish chitinous epidermis. A very common and destructive species found boring in wood. Teredo bartschi Clapp Bartsch’s Shipworm South Carolina to north half of Florida to Texas. Introduced to San Diego, California. Shell close to T. navalis, but with the auricle typically semi-circular rather than sub-triangular in outline. Pallets: stalk long; blade short and deeply excavated at the top. Only the distal half of the blade is invested with periostracum, which is light horn-colored and semi-transparent, per- mitting the calcareous portion to be seen within as an irregular, hourglass- shaped structure with a deep sinus on either side. A common species. Teredo diegensis Bartsch | San Diego Shipworm Southern half of California. And south? 468 American Seashells Shell similar to that of T. zavalis, but smaller, more finely sculptured and transparent, and with numerous, closely set ridges. Pallets: blade with an oval, calcareous base, surmounted by a horny cap, amber to black in color. The horny portion is commonly deeply excavated at the tip, but may be cut off bluntly. The two elements of the blade come apart very easily. T. townsendi Bartsch is the same according to Kofoid and others. Suborder ANOMALODESMACEA Superfamily PANDORACEA Family LYONSIIDAE Genus Lyonsia Turton 1822 Lyonsia hyalina Conrad Glassy Lyonsia Plate 28u Nova Scotia to South Carolina. ¥% to % inch in length; very thin and fragile. Semi-translucent and whitish to tan. Shell elongate, with the anterior end somewhat obese and the posterior end tapering and laterally compressed. Without teeth in the weak hinge, but with a small, free, elongate, calcareous ossicle inside just under the small, inflated, anteriorly pointing beaks. Periostracum very thin, with numerous raised radial lines. Commonly has tiny sand grains attached. Common from low water to 34 fathoms. Lyonsia hyalina floridana Conrad, known from the west coast of Florida to Texas, is very similar, differing only in being % as high as long (instead of %) and in having a narrower, more rostrate posterior end. Common. Lyonsia arenosa Moller Sanded Lyonsia Greenland to Maine. Alaska to Vancouver. % to %4 inch in length, resembling yalina, but much less obese, with a heavier, greenish-yellow periostracum, and with its posterior end more oval and higher than the anterior end. The dorsal margin of the right valve behind the beak overlaps that of the left valve considerably. There is no posterior gape as in hyalina. Like other species in the genus, it glues sand grains to itself. Moderately common from low water to 60 fathoms. Lyonsia californica Conrad California Lyonsia Puget Sound to Lower California. 1 inch in length, very thin, fragile and almost transparent. Quite elongate and moderately obese. Beak area swollen. Posterior end tapering and later- PANDORIDAE 469 ally compressed. Outer surface whitish (opalescent when worn), commonly with numerous, weak, radial, dark lines of periostracum. Interior glossy and with an opalescent sheen. Ossicle inside, under hinge, is opaque-white. Very similar to our figure of the Atlantic byalina. Common in sandy mud bot- toms of many California sloughs and bays down to 4o fathoms. Genus Entodesma Philippi 1845 Subgenus Agriodesma Dall 1909 Entodesma saxicola Baird Northwest Ugly Clam Plate 29m Alaska to San Pedro, California. 2 to 5 inches in length. A very peculiar, ugly and misshapen clam found along the shore burrowing into rocks. Generally oblong in shape, with the posterior end flaring and gaping. Covered with a thick, rough, brown peri- ostracum which partially flakes off when dry. Interior brownish tan to whitish with a slight opalescence. Hinge without teeth, but with a rather large, oblong, whitish ossicle lying under the internally placed ligament. Moderately common from Washington to southwest Alaska. Genus Mytilimeria Conrad 1837 A peculiar, bladder-shaped, very thin shell found embedded in compound ascidians or sea squirts. Mytilimeria nuttalli Conrad Nuttall’s Bladder Clam Plate 29q Alaska to Lower California. 1 to 2 inches in length, obliquely oval, inflated, very fragile, opaque with a thin, brownish periostracum. Beaks small and spiral. No teeth in the weak hinge, but a small, calcareous ossicle is present. Color white with underlayers of slightly pearly material. Common under rocks at low tide to 10 fathoms, always embedded in compound ascidians or sea squirts. Family PANDORIDAE Genus Pandora Chemnitz 1795 (Opinion 184) Pandora trilineata Say Say’s Pandora Figure 96b Cape Hatteras, Nerth Carolina, to Florida and Texas. % to 1 inch in length, almost half as high; half-moon-shaped in outline, and with a strong, squarish ridge along the hinge margin which extends pos- teriorly into a fairly long rostrum. Valves very flat, the entire shell very 470 American Seashells compressed. Beaks tiny, quite near the rounded anterior end. Right valve smoothish and translucent cream. Left valve more prominently divided into 2 portions by a slight radial groove, anterior to which the shell is dull cream, and posterior to which the shell is more glossy but with microscopic con- centric growth lines. Sometimes slightly iridescent. Interior pearly. Mod- erately common in sand below low water to 60 fathoms. Pandora arenosa Conrad, the Sand Pandora, (Carolinas to southeast Florida) is commonly dredged by amateurs. It is very much like ¢rilineata, but never over % inch in length, completely lacking the rostrum and with a quite convex left valve which has an external radial rib below the hinge margin ridge. Common. P. carolinensis Bush is this species. Figure 96. Atlantic Pandoras. a, Pandora bushiana Dall, 4% inch (Florida); b, P. trilineata Say, *4 inch (Atlantic Coast); c, P. gouwldiana Dall, 1 inch (northern Atlantic Coast). Pandora gouldiana Dall Gould’s Pandora Figure 96c Gulf of St. Lawrence to Cape May, New Jersey. % to 1% inches in length, similar to trilineata, but less elongate with the height slightly more than half the length. The posterior rostrum on the hinge line is very short, stubby and turned up. The shell is opaque, chalky and commonly worn away, showing the pearly underlayers. Margin of valves bordered with blackish brown periostracum. Common from intertidal areas to 20 fathoms. Subgenus. Kennerlia Carpenter 1864 Pandora filosa Carpenter Western Pandora Alaska to Ensenada, Lower California. THRACIIDAE 471 1 inch in length, thin but not too fragile, opalescent-white with a brownish border of periostracum. Interior opalescent. Valve semi-circular in outline. Right valve almost flat and with a single, fairly large tooth which juts laterally. Left valve moderately convex. The posterior dorsal margin is almost straight, the posterior end somewhat drawn out into a rostrum. Moderately common from 1o to 75 fathoms. Pandora bilirata Conrad (Alaska to Lower California. Dredged) 1s half as large, not rostrate posteriorly, and with 2 strong radial ribs on the posterior dorsal margin of the left valve. Pandora granulata Dall (Santa Barbara south to La Paz, Mexico) is much like bilirata, but half its size, more elongate, and the 2 radial ribs are granulated. Family THRACIIDAE Genus Thracia Blainville 1824 Shells up to 4 inches in size, thin, chalky in texture, beaks so close that the right one becomes punctured by the left beak; ligament external; shell commonly moderately rostrate at the posterior end; right valve fatter than the left. Thracia conradi Couthouy Conrad’s Thracia Plate 28y Nova Scotia to Long Island Sound, New York. 3 to 4 inches in length, about 4% as high. Valves obese and chalky-white. Hinge without teeth, only thickened considerably behind the beak and be- low the large, wide, external ligament. Right beak always punctured by the beak in the left valve. Pallial sinus U-shaped but not very deep. Posterior end of valves slightly rostrate and with a weak radial ridge. Rarely washed ashore. Not uncommon offshore and down to 150 fathoms. Thracia trapezoides Conrad Common Pacific Thracia Alaska to Redondo Beach, California. 2 inches in length and not quite so high; thin, chalky, and with the posterior end broadly rostrate. The beak of the right valve has a hole punc- tured in it by the beak of the left valve. The posterior rostrated part of the valve is set off by a broad, radial, depressed furrow which is bordered by a low, rounded, radial ridge. Color drab, grayish white. Commonly dredged off the west coast. Compare with T. curta Conrad. 472 American Seashells Thracia curta Conrad Short Western Thracia Alaska to Lower California. 1 to 1% inches in length, very similar to trapezoides, but suboval and lacking the prominence of rostration. It is very close in shape to our illus- tration of the Atlantic T. conradi. A moderately common species. John Q. Burch reports that it is relatively abundant at San Onofre, California, in the rubbly reef at extreme low tides. It has also been taken from wharf pilings, and it is commonly dredged in over 20 fathoms on shale bottoms. Genus Cyathodonta Conrad Similar to Thracia, but the right beak is without a round hole, and the ligament is internal on a definite chondrophore, and the valves are with oblique, concentric undulations. This is sometimes considered a subgenus of Thracia, not without justification. There is only one species on the Pacific Coast of America. Cyathodonta undulata Conrad Wavy Pacific Thracia Plate 31s Monterey, California, to Tres Marias Islands, Mexico. 1% inches in length, subovate, very thin and fragile, white, and with obliquely concentric undulation which are largest at the anterior end, but disappear toward the posterior end of the shell. Minute, crowded, granu- lated, radial lines are also present. Uncommon. C. dubiosa Dall and C. pedroana Dall appear to be this species. Family PERIPLOMATIDAE Genus Periploma Schumacher 1817 Shell small, oval, right valve fatter than the left, with a slight pearly sheen, hinge with a narrow, oblique spoon and a small, free, triangular litho- desma; ligament absent; anterior muscle scar long and narrow, the posterior one small and ovate. Periploma papyratium Say Paper Spoon Clam Plate 28w Labrador to Rhode Island. % to 1 inch in length, oval, moderately compressed, thin-shelled, and dull-white with a thin, yellowish-gray periostracum. Beaks slit or broken by a short, radial break. Spoon-like chondrophore faces downward and is rein- forced by a sharp, curved rib which runs to the inner surface of the valve PERIPLOMATIDAE ani in a ventral direction. Sculpture of irregular, fine, concentric growth lines. A weak radial groove runs from the beak to the anterior part of the ventral edge. Moderately common in dredge hauls from 1 to 200 fathoms. P. papy- raceum is an incorrect spelling for this species. Periploma fragile Totten, the Fragile Spoon Clam (Labrador to New Jersey, 4 to 40 fathoms), differs in being more rostrate anteriorly, the beaks pointing more forward and placed more anteriorly. Its chondrophore is more horizontal to the hinge line. Periploma inequale C. B. Adams Unequal Spoon Clam Plate 28x South Carolina to Florida and to Texas. % to 1 inch in length, oblong, the left valve more inflated and slightly overlapping the right valve. Fragile and pure white. Beaks close together, each with a short, radial break or slit in the surface. An oblique, low keel runs from the beaks to the anterior ventral margin of the valve. The keel is bounded posteriorly by a groove. Sculpture consists of microscopic, con- centric scratches. Hinge with a single, large, spoon-shaped tooth or chondro- phore, above which is a deep slit where the small, free, triangular lithodesma fits. This species is especially abundant along certain Texas beaches. P. inaequivalvis Schumacher from the West Indies has not been found in the United States, despite several erroneous records. Periploma planiusculum Sowerby Common Western Spoon Clam Plate 31x Point Conception, California, to Peru. 1 to 1% inches in length, ovate, thin, with weak, concentric lines of growth. Right valve fatter than the left; chondrophore ovate-trigonal, its longer diameter directed forward and reinforced posteriorly by an elongate, rib-like buttress. Commonly washed ashore on southern Californian beaches. Periploma discus Stearns Round Spoon Clam Figures 97a; 281 Monterey, California, to La Paz, Lower California. 1 to 1% inches in length, similar to planiusculum, but almost circular in outline, except that the posterior end is slightly lengthened into a short, broad, blunt rostrum. Uncommonly dredged in mud bottom at several fathoms; rarely washed ashore after storms. 474 American Seashells Subgenus Cochlodesma Couthouy 1839 Periploma leanum Conrad Lea’s Spoon Clam Plate 28v Nova Scotia to off North Carolina. 1 to 1% inches in length, ovate, quite compressed, fairly fragile and white in color. Smoothish. The beaks located near the center of the dorsal edge of the valves have a natural, radial crease at the anterior end. Chondro- phore large, points ventrally and is reinforced anteriorly by a low, sturdy ridge. The muscle scar above the pallial sinus is commonly quite silvery. Periostracum thin and yellowish. Uncommon just offshore. This was put in a separate subgenus, Aperiploma, by Habe in 1952. FIGURE 97. Spoon and Dipper Clams. a, Periploma discus Stearns, 1% inches (California); b, Cuspidaria glacialis Sars, 1 inch (Atlantic Coast); e and d, Verti- cordia ornata Orbigny, % inch (Atlantic Coast). Order SEPTIBRANCHIA Family VERTICORDIIDAE Genus Verticordia Sowerby 1844 Subgenus Trigonulina Orbigny 1846 Verticordia ornata Orbigny Ornate Verticord Figure 97c, d Massachusetts to south half of Florida and the West Indies. % inch in length, oval to round, compressed and with about a dozen strong, sharp, curved radial ribs on the anterior %4 of the valve. The ribs extend beyond the ventral margin to give a strongly crenulate margin. Exterior dull and cream-white; interior very silvery. Commonly dredged off our east coast from 5 to 200 fathoms. Verticordia (Haliris) fischeriana Dall is similar, but much fatter, 4 inch in length, and with about 28 small, finely beaded, radial ribs over the CUSPIDARITDAE ashe) entire surface of the valve. Uncommon, 10 to 100 fathoms, from North Carolina to the West Indies. Called Fischer’s Verticord. Family POROMYIDAE Genus Poromya Forbes 1844 Shell small, fragile; sculpture of fine granules in radial series. Hinge of right valve with a strong cardinal tooth in front of a wide chondrophore; hinge of left valve with a small cardinal tooth behind and above the chondro- phore. Poromya granulata Nyst Granular Poromya Plate 30s Cape Cod, Massachusetts, to east Florida and Cuba. %4 to ¥% inch in length, ovate, inflated and fragile. Beaks inflated and turned forward. Exterior cream-white, with an irregular coating of fine granules which resemble sugar-coating. In fresh material, this granular deposit is also found on the inner margins of the valves. Slightly gaping at the posterior end. Interior of valves silvery white. Commonly dredged in a few fathoms of water off eastern Florida. Poromya rostrata Rehder (Cape Hatteras, North Carolina, to east Flor- ida and the West Indies, 60 to 100 fathoms) 1s distinctly rostrate posteriorly and the granules are larger, more evenly spaced and generally cover the en- tire outer shell. It is relatively uncommon. Family CUSPIDARIIDAE Genus Cuspidaria Nardo 1840 Shell small, globose in front, rostrate behind. Hinge with a posterior lateral tooth in the right valve. External ligament elongated. Resilium in a small, spoon-shaped fossette. Lithodesma distinct and semi-circular. Cuspidaria glacialis Sars Glacial Cuspidaria Figure 97b Nova Scotia to Maryland. Gulf of Mexico? Alaska. I to 1% inches in length, rostrum moderately long and compressed lat- erally. Main part of valves fat and round. Sculpture consists of small, irreg- ular growth lines. Periostracum grayish white. Shell cream to white. A common species dredged from 64 to over 1400 fathoms. C. jeffreysi in the south is very similar, but smaller, with a rostrum which in cross-section is much more oval and less compressed, and with hardly any periostracum. 476 American Seashells Cuspidaria rostrata Spengler Rostrate Cuspidaria Plate 32) Cape Cod, Massachusetts, to the West Indies. ¥% to 1 inch in length, with a tube-like rostrum which is % the length of the entire shell. The rostrum points slightly downward. Shell fairly smooth with moderately coarse, concentric growth lines. Whitish in color and sometimes with granular lumps of gray mud attached to the rostrum. Moderately common in deep water (65 to over 1600 fathoms). Cuspidaria jeffreysi Dall Jeffrey’s Cuspidaria Southern Florida and the West Indies. ¥s inch in length, smoothish with only fine lines of growth. Rostrum moderately long; main part of shell round and fat. Similar to glacialis in the north which, however, is larger, more compressed, and whose rostrum points slightly downward instead of directly posteriorly as in this species. Creamy white in color. Uncommonly dredged in waters over 100 fathoms off Miami. Subgenus Leiomya A. Adams 1864 Cuspidaria granulata Dall Granulated Cuspidaria Off Miami, Florida, and the West Indies. % inch in length, similar to jeffreysi, but snow-white and covered with numerous, small, opaque-white granules. Uncommon from 30 to 100 fathoms. Genus Cardiomya A. Adams 1864 With strong, sharp radial ribs; fossette more vertical and prominent, otherwise like Cuspidaria. Cardiomya costellata Deshayes Costate Cuspidaria North Carolina to south Florida and the West Indies. ¥% inch in length, fragile, with a short rostrum, and with a few promi- nent radial ribs just in front of the rostrum which gives the ventral margin of the valve in that area a scalloped edge. Anteriorly, the radial ribs are closer together, but weaker, and are rarely present at the anterior end of the shell. Additional ribs may develop in older specimens and become more even in size. (C. multicostata Verrill and Smith may be the old form and C. gemma Verrill and Bush the young form.) Commonly dredged off eastern Florida. CUSPIDARIIDAE ATT Cardiomya pectinata Carpenter Pectinate Cuspidaria Puget Sound, Washington, to Panama. % inch in length; anterior end globular, bearing 8 to 12 strong radial ribs (there may be smaller ribs between the main ones). Posterior end drawn- out like a short handle and bearing 2 to 4 weak, longitudinal riblets. Color dull-gray with a glossy, grayish white interior. Commonly dredged offshore. Consider the case of the oyster Which passes its time in the moisture. Of sex alternate, It chases no mate, But lives in a self-contained cloister. Jory W. Heperetu (Maryland Tidewater News September 1950) GEUAPaALE R Xt Squid, Octopus and Cuttlefish Class CEPHALOPODA Subclass TETRABRANCHIA This subclass, which includes the Chambered Nautilus and about 5000 species of fossil and extinct Ammonites, is not represented in American waters. The living species of Nautilus from the Indo-Pacific are character- ized by a large, chambered, external shell, by two pairs of gills, and by their numerous suckerless arms. Subclass DIBRANCHIA All of the living cephalopods with the exception of Nautilus belong to this subclass which is characterized by animals that have one pair of gills, 8 or 10 arms which bear rows of suckers, and whose shell is internal or en- tirely absent. Order DECAPODA (Spirula and Squid) With 10 arms, 2 of which are the long tentacular arms; body long and cylinder-shaped. An internal shell is present in most cases, and may be cal- careous (the cuttlebone) or thin and horny (squid pen). The small suckers on the arms are usually set on small stalks or peduncles and their apertures are armed with horny rings or hooks. Family SPIRULIDAE Genus Spirula Lamarck 1799 Spirula spirula Linné Common Spirula Figure 98 Cape Cod to the West Indies. Worldwide. 478 SEPIOLIDAE 479 The rather fragile, white shell is a chambered cone coiled in a flat spiral, usually less than 1 inch in diameter and with the coils not in contact. Each small chamber in the shell is divided from its neighbor by a nacreous-white, Figure 98. The white, inch-long shells (a and b) of Spirula spirula Linné are commonly washed ashore on southern beaches, but the squid-like animal (c) lives at great depths and is very seldom captured alive. concave, fragile septum or wall. There is a small siphonal tube running back into the shell and piercing the septa. These shells are cast up on the beaches quite commonly. The body is short and cylindrical, and surrounds the shell almost completely except for two small areas. The 8 sessile arms and 2 pe- dunculated tentacular arms are very short. Myopsid Squid—transparent cornea over eyes; pupils crescent-shaped Family SEPIOLIDAE Genus Rossia Owen 1828 Short, “tubby” animals whose bodies are rounded at the end. The man- tle edge is free all around. 8 arms short with 2 to 4 rows of spherical suckers which have smooth, horny rims. The two tentacular arms can be almost entirely withdrawn. The internal pen is slender, lanceolate and very thin and delicate. The rather large, semi-circular fins are on the middle of the sides of the body. Eye with small eyelid on the lower side, none above. No sulcus or notch on front of the eye. Rossia pacifica Berry Pacific Bob-tailed Squid Alaska to San Diego, California. Total length, not including the tentacles, 3 to 4 inches. Body smooth, mantle flattened above and below, rounded behind. Fins large, semi-circular or subcordate, with a free anterior lobe, their attachment more or less oblique to the general plane of the body. Color in life unknown; in alcohol, reduced to brownish buff, heavily spotted above and in less degree below with pur- plish chromatophore dots, which extend even over the fins, although fewer on under surfaces and margins. This is the only Rossia recorded on the Pacific Coast, and it is rather abundant from 9 to 300 fathoms. 480 American Seashells Subgenus Semirossia Steenstrup 1887 Rossia tenera Verrill Atlantic Bob-tailed Squid Figure 99d Nova Scotia to southeastern Florida. 3 to 4 inches in length, including mantle and longest arm. A small and delicate species, very soft, translucent, and delicately rose-colored when liv- ing. Internal pen small, very thin and soft. Length of each side fin is about % of the body, and the base of attachment of the fin is about % the body- length. Arms unequal, the dorsal ones considerably shorter. This species is characterized by the larger size of the suckers located along the middle of the lateral arms. Commonly dredged from 18 to 233 fathoms. Formerly listed as Heteroteuthis tenera Verrill. R. equalis Voss, dredged off southeast Florida, differs in having the suckers on the lateral arms about equal in size. Family SEPIIDAE Genus Sepia Linné 1758 The common cuttlefish squid of Europe is not represented in our waters, although in rare instances the cuttlefish bone or internal shell has been found in western Atlantic waters. The cuttlefish bone is an oblong, six-inch or so, very light slab of chalky material, rounded at one end, pointed at the other. It is used in the manufacture of toothpaste, and is tied to the bars of canary cages for the birds to peck at as a source of lime. Ink from Sepia was at one time a main source for durable, black writing ink. Family LOLIGINIDAE Genus Loligo Schneider 1784 Ten-armed, with elongate, tapering, cylindrical body and large, termi- nal, triangular fins. Arms with two rows of suckers provided with horny, dentated rings; fourth left arm hectocotylized in the males. Tentacular arms with four rows of suckers on their clubs. Internal pen horny, lanceolate with its shaft keeled on the under side. The female receives the sperm sacs of the male upon a specially developed pad below the mouth. In the genus Lolli- guncula, the sperm sacs are received upon a callused patch within the mantle near the left gill. Subgenus Loligo s. str. Loligo pealei Lesueur Atlantic Long-finned Squid Figure gga Nova Scotia to both sides of Florida. LOLIGINIDAE 481 es rat eo eie estas, eemaisirate 780: Figure 99. Atlantic Cephalopods. a, Loligo+pealei Lesueur (length: 1 to 2 feet); b, Illex illecebrosus Lesueur (1 to 1% feet); ce, Architeuthis harveyi Kent (40 to 55 feet); d, Rossia tenera Verrill (3 to 4 inches); e, Argonauta hians Solander (2 to 3 inches); f, shell of same; g, Lolliguncula brevis Blainville (5 to 10 inches). (From A. E. Verrill 1879.) 482 American Seashells Total length, including tentacular arms, 1 to 2 feet. Easily recognized by the accompanying illustration which shows the rather long, triangular fins. The proportion of fin-length to mantle-length varies from 1 to 1.8 and down to a ratio of 1 to 1.5. Adult males have the left ventral arm conspicuously hectocotylized (see fig. gga). A very abundant species caught commercially for fish bait in New England. Living specimens are very beautifully speckled with red, purplish and pink. Loligo opalescens Berry Common Pacific Squid Puget Sound, Washington, to San Diego, California. Total length, not including tentacles, 6 to 8 inches. This is the common squid of the Pacific Coast and can be readily recognized by the accompany- ing illustration. At certain seasons, they occur in great schools by the thou- sands. Genus Lolliguncula Steenstrup 1881 Lolliguncula brevis Blainville Brief Squid Figure 99g Delaware Bay to Florida and to Brazil. Total length, including the tentacular arms, 5 to 10 inches. Charac- terized by its short, rounded fins, very short upper arms, and large color spots. Underside of fins white. Consult the figure. Common in warm wa- ters. This is L. brevipinna Lesueur and L. hemiptera Howell. Genus Sepioteuthis Blainville 1824 Similar to Loligo, but with large, triangular fins that extend along the entire length of the mantle, thus giving the animal an oval outline. Siphonal funnel attached to the head by muscular bands. There is a strong wrinkle behind the eye. Sepioteuthis sepioidea Blainville Atlantic Oval Squid Bermuda, Florida and the West Indies. Total length, including tentacular arms, 4 to 5 inches. Characterized by the long fins which commence a short distance behind the mantle edge (14 to % inch). Internal pen thin, lanceolate and without any marginal thick- enings. Skin regularly and closely spotted with purple dots. The eggs are large, 5 to 8 mm. in diameter, and laid in long jelly tubes. A rather common, warm-water species. OMMAST REPHIDAE 483 Genus Doryteuthis Naef 1912 Doryteuthis plei Blainville Plee’s Striped Squid Florida and the West Indies. Up to 8 inches in length, including the tentacular arms. Characterized by the long, narrow, slightly wavy, dark-colored bands running back along the side of the mantle. The rest of the mantle is moderately covered with small round dots. The body is long and slender, the triangular fins on the last third of the mantle, and the arm suckers do not have pointed teeth on the horny circles. A common surface-living species of the Caribbean region. Oigopsid Squid—eyes naked in front, pupils circular; eyelids Family ARCHITEUTHIDAE Genus Architeuthis Steenstrup 1857 Architeuthis harveyi Kent Harvey’s Giant Squid Figure 99c Newfoundland Fishing Banks. Total length 40 to 55 feet. Body stout, nearly round, swollen in the middle. Arms nearly equal in length, all bearing sharply, serrated suckers. Tentacular arms 4 times as long as the 8 sessile arms. The peculiar backward pointing tail fins separate this species from A. princeps Verrill, another giant squid found in the same area. A large well-preserved specimen of any giant squid is worth its weight in gold. No large specimens have been brought back from the fishing banks in many years. They may occasionally be washed ashore from Nova Scotia north. If you find one, take photographs if possible, and notify one of the leading museums. Giant squid of unknown identity have been seen in the Gulf of Mexico. Family OMMASTREPHIDAE Genus Illex Steenstrup 1880 Resembling Loligo somewhat, but with half-hidden eyes, the lids free and with a distinct notch or sinus in front. Internal pen narrow along the middle portion, and with three ribs. There are 8 rows of tiny suckers on the end section of the 2 long, tentacular arms. Further study may show that the genus //Jex is the same as Ommastrephes Orbigny 1835. Illex illecebrosus Lesueur Common Short-finned Squid Figure ggb Greenland to North Carolina and the Gulf of Mexico. 484 American Seashells Total length, including tentacular arms, 12 to 18 inches. A common squid characterized by the small opening to the eyes and the small, narrow sinus or notch in front of the eyes, and by the proportion of fin-length to mantle-length which is roughly 1 to 3. The sides of the head, back of the eyes, have a rather prominent, transverse ridge, back of which the head sud- denly narrows to the neck. Under surface of head with a deep, smoothish excavation to receive the dorsal half of the siphonal tube. In males, either the left or right ventral arm is hectocotylized. A very common species used for fish bait. It may be seen in large schools near shore, especially in summer in New England. Genus Sthenoteuthis Verrill 1880 Very similar to I//ex in almost every way, but the sucker-bearing area includes less than one half the total length of the tentacular arms. The larger suckers on the tentacular club are strongly toothed, with an additional large tooth in each of the four quadrants. Sthenoteuthis bartrami Lesueur Flying Squid Worldwide. 2 to 3 feet in total length, resembling the common Ilex, but more slen- der, with shorter fins, and with 4, not 8, rows of tiny suckers on the end of the 2 long tentacular arms. Preserved specimens show a distinct dark, purple- brown dorsal stripe. In life, the colors are very brilliant and are continually changing. Along the middle dorsal line there is a broad violet stripe with a stripe of reddish yellow on each side of it. Body elsewhere bluish; fins rosy. Skin covered with small, red-violet chromatophore dots. On the eyes there are two elongated spots of brilliant blue, and below a bright spot of red. Color of ink reported to be a coffee-and-milk color. A common ocean-going species which swims with great speed, and not infrequently jumps out of water and lands on the decks of ships. Like most squid, it is attracted by artificial light, Order OCTOPODA The octopods have only 8 arms and are without the 2 long tentacular arms that are characteristic of the squid. The suckers on the arms are with- out stalks and are not equipped with horny rings. No internal pen or shell. This order includes the many forms of Octopus and the Paper Nautilus, Argonauta, The female Argonauta secretes a shell to hold her eggs. OCTOPODIDAE 485 Family ARGONAUTIDAE Genus Argonauta Linné 1758 Pelagic octopods in which the dorsal arms of the female are broadly expanded into glandular membranes that secrete and hold a delicate, cal- careous shell for containing the eggs. The males are considerably smaller than the females, do not have a shell, and the third right arm is modified into a detachable copulatory organ which persists separately for a certain length of time in the mantle cavity of the female. Argonauta argo Linné Common Paper Nautilus Plates 1c; 26y Worldwide in warm waters. 4 to 8 inches in length, quite fragile, laterally compressed with a narrow keel, numerous sharp nodules which in the early part of the shell are stained with dark purplish brown. Rest of shell opaque, milky-white. Occasionally washed ashore. A. americana Dall is the same. Argonauta hians Solander Brown Paper Nautilus Figure gge, f Worldwide in warm waters. Similar to A. argo, but smaller, much “fatter” with a rapidly broadening keel that bears larger and fewer nodules. Color brownish white with darker stains on the early part of the keel. Uncommonly washed ashore. Family TREMOCTOPODIDAE Genus Tremoctopus Delle Chiaje 1829 Tremoctopus violaceus Delle Chiaje Common Umbrella Octopus Pelagic in warm waters. Worldwide. Total length, including the arms, 3 to 6 feet. Deep purplish red in color. Characterized by the long skin webs between the four dorsal arms, and the two large holes in the body near the base of the third arm and in front of the eyes. The species is gregarious, and is occasionally washed ashore on the east coast of Florida. Family OCTOPODIDAE Genus Octopus Lamarck 1798 There are only five valid species of littoral Octopus so far recorded along the Atlantic Coast. There are a few deep water ones, some of which 486 American Seashells belong to closely related genera. The characters most relied upon in dis- tinguishing species are relative length of the arms, the skin surface, the nature and relative length of the small ligula (the tiny pad-like extension on the end of the third right arm in the males, 1.e., the hectocotylized arm). The number of gill plates and color pattern are used to a less extent. The eight arms have each been given a number, in order that com- parisons may be made. This is done by setting the octopus down with the body up, and the arms spread-eagle out in all directions. Turn the octopus so that the two eyes are on the side away from you. By going from the eyes out to the mantle edge away from you, and choosing the first arm to the right, you have located the first arm. Further clockwise are the second, third and fourth right arms. Instead of counting further (fifth arm, etc.), return to the center again, and count to the left—hence, the first, second, third and fourth left arms. When giving an arm formula, only the right ones are gen- erally given, and they are set down in order of large to smaller size. Hence, 4.3-1.2 means the fourth arm is the largest, the second one the smallest in length. It may be pointed out, that on rare occasions an octopus may acci- dentally lose an arm. There are two simple sets of measurements (all in millimeters) which are Important in distinguishing the species of Octopus. The first is the mantle-arm index which simply means the comparison of the length of the mantle (measure from the round, bulbous “head” end to a point just between the eyes) with the length of the longest arm (turn the octopus over, measure from the mouth to the tip of the longest stretched-out arm). An index is obtained by multiplying the mantle-length by 100 and then dividing the result by the arm- length. The ligula index is obtained only from males and from the third right arm which is a modified sex organ. The ligula is measured from tip to the last sucker. The arm length is Se dned as explained in the preceding para- graph. The index is: length of ligula, multiplied by 100, the result divided by the total arm-length. The number of gill plates and the size of eggs are determined by cutting a deep slit in the body. Octopus vulgaris Lamarck Common Atlantic Octopus Figure 1004 Connecticut to Florida and the West Indies. Europe. Length, including the longest arm, 1 to 3 feet (the latter would give a radial spread of about 7 feet). Mantle-arm index in Florida and North Carolina is about 25 (that is, the arms are 4 times as long as the mantle). Ligula-index below 2.5. Gill plates 7 to 9 (in Bermuda, usually 10 or 11). In life, skin smoothish; preserved, it is rugose with variousty shaped warts. Eggs 3 mm, or less in length. A common harmless species found hidden away =a OCTOPODIDAE 487 under large rocks and crevices near shore. This is O. rugosus of authors, O. americanus Blainville and O. carolinensis Verrill. Octopus macropus Risso of the West Indies (and possibly Key West) has its first arm the largest and longest, has a ligula-index up to 14, and a wart over one side of the eye. The skin in preserved material has small reddish warts. The eggs are less than 2 mm. in length (see fig. 100e). Figure 100. Atlantic and Pacific Octopus. The tip end or ligula of the third right arm in the male. a, Octopus vulgaris Lamarck; b, O. burryi Voss; ¢, O. briareus Robson; d, O. jowbini Robson; e, O. macropus Risso; f£, O. hongkongensis Hoyle (Pacific). Octopus briareus Robson Briar Octopus Figure 100c Southern Florida and the West Indies. Length, including longest arm, 1 to 1% feet. Arms fairly thick at the bases, quite long, especially the third and sometimes the second. Mantle- index 13 to 30, but usually about 17. Ligula-index about 4. Gill plates 7, rarely 8. Skin smoothish, or finely granular in preserved material; in life, pinkish brown to red-mottled. Eggs elongate, translucent-white, 10 to 12 mm. in length and with equally long attachment stalks. Fairly common be- tween tides under large coral blocks on the Lower Florida Keys. Octopus burryi Voss Burry’s Octopus Figure roob Southern half of Florida and the Gulf of Mexico. Length, including the longest arm, 6 to 10 inches. Characterized by a broad band of dark purple on the top surface of the arms, and, in preserved specimens, by the skin which is covered with closely set, round papillae or warts. Gill plates 8 to 10 in number. Ligula-index 4 to 5. This is a recently described species named after a famous Florida collector, Leo L. Burry of 488 American Seashells Pompano Beach, Florida. It 1s a moderately common, fairly shallow-water species. Octopus joubini Robson Joubin’s Octopus Figure 1ood Southern half of Florida, and the West Indies. A small species with a length, including the longest arm, of from 4 to 6, rarely 7 inches. The arms are short, with a mantle-arm index of about 4o to 50. Ligula-index about 6 to 7. Gill plates 5 or 6 usually. Skin smoothish, except for little pimples at scattered intervals. In this species, the longest arm is only 2 or 3 times the mantle-length, while in O. briareus the longest arm is 5 or 6 times as long as the mantle. Eggs large, amber-colored, and about 7 to 1o mm. in length. Occasionally cast ashore in fair numbers on the west coast of Florida. O. mercatoris Adam 1937 is the same. Formerly placed in the genus Paroctopus which is now considered of no value. Octopus hongkongensis Hoyle Common Pacific Octopus Figure roof Alaska to Lower California. Japan to south China. Length, including longest arm, % to 3 feet (possibly with a radial spread of nearly 28 feet in Alaskan waters). Skin in preserved specimens covered everywhere by numerous small, pimple-like tubercles with star-shaped bases, and by many heavy, much interrupted, longitudinal wrinkles. Above each eye there is a rather small, conical wart and with a very large, pinnacle-like protuberance behind it. Ligula index 4 to 7. The web between the second and third arms usually extends out to a quarter of the arm’s length. Flse- where the webs are shorter. The commonest littoral Octopus on the Pacific Coast found from shore to 100 fathoms. This 1s O. punctatus Gabb. O. californicus Berry, an off-shore species, has a large lingula with an index of 14 to 17. The skin in preserved material is covered with numerous, large stellate warts. The Californian Deep-water Octopus. Octopus bimaculatus Verrill Two-spotted Octopus Los Angeles, California, to Lower California. Total length % to 2 feet. Characterized by a large, distinct, round, dark spot in front of each eye near the base of each third arm. Eggs small, 1.8 to 4.0 mm. in length with long stalks, attached in festoons. Mantle-arm index usually 22, but ranging from 14 to 29. Ligula-index 2.0, not significant in separating this species from bimaculoides. Fairly common. Lives in the lower part of the intertidal zone down to several feet where there is rock bottom. OCTOPODIDAE 489 Aside from egg-size and egg-clusters and mantle-arm index, there is great difficulty in separating this species from O. bimaculoides Pickford which lives nearby in shallower water where there is mud present. Octopus bimaculoides Pickford Mud-flat Octopus Los Angeles, California, to Lower California. Almost identical with O. bimaculatus Verrill. Eggs large, 9.5 to 17.5 mm. in length, with shorter stalks, attached in small clusters. Mantle-arm index 34, but ranging from 29 to 39. Fairly common in shallow water among rocks where mud is present. Adults are somewhat smaller than bimaculatus. GEA PUE RO xi Guide to the Molluscan Literature Tue literature dealing with mollusks is very extensive and widely scattered in many journals and books. Since 1900, approximately 60,000 separate articles on mollusks have appeared. Most of these are listed according to author and subject matter in the Zoological Record (printed for the Zoologi- cal Society of London and in its 86th volume). This valuable journal may be found in any large museum or university library. The bibliography in- cluded here is intended only as a guide or lead to the more important books and articles dealing primarily with American marine mollusks, GENERAL TEXTS Bronn, H. G. 1892-1940: Klassen und Ordnungen des Tierreichs. Leipzig. Sev- eral large volumes on biology and anatomy of mollusks. Technical. Monu- mental work in German by H. Simroth, H. Hoffmann, F. Haas and others. Large bibliographies. Butioucu, W. S. 1950: Practical Invertebrate Anatomy. 463 pp. Macmillan, N.Y. Large section on anatomy and dissecting techniques (pp. 317-391, 34 figs.) on mollusks. Cooker, A. H. 1895: Mollusca. Volume 3 of the Cambridge Natural History Series. 459 pp., 311 figs. Macmillan, N.Y. Very good, but out-of-date, gen- eral introduction to mollusks. Jounston, G. 1850: An Introduction to Conchology. 614 pp., 102 figs. J. Van Voorst, London. Interesting reading, history and lore, but very much out- of-date. MacGinitir, G. E. and N. 1949: Natural History of Marine Animals. 473 pp. McGraw-Hill, N.Y. Ecology and habits of marine mollusks, pp. 327-401. 490 Guide to the Molluscan Literature 491 PELSENEER, PAauL 1906: Mollusca. A Treatise on Zoology (vol. 5). 355 pp., 301 figs. Adam and C. Black, London. Excellent college-level text. Somewhat out-of-date. THIELE, J. 1929-35: Handbuch der Systematischen Weichtierkunde. 4 vols. 1154 pp. Jena, Germany. Standard text on classification and arrangement of mol- lusks. Tryon, G. W. 1882-84: Structural and Systematic Conchology. Philadelphia. 3 vols. Vol. 1, 312 pp., 22 pls., contains introductory matter, biology, history and anatomy. Vol. 2, 430 pp., 68 pls., contains general systematic account of marine forms. Vol. 3 deals with land forms. Useful, but considerably out- of-date. POPULAR BOOKS We have listed most of the recently published popular books, but do not necessarily recommend all that are included. The prices listed here are only approximate, especially for those available only second-hand. General and Foreign ALLAN, Joyce 1950: Australian Shells. 470 pp., 12 colored pls., 28 halftones, 110 figs. Georgian House, Melbourne. $7.50. Bartscu, P. 1931: Mollusks. In Smithsonian Scientific Series, vol. 10, pt. 3, pp. 251-357, 36 pls. Series Publishers, N.Y. $8.25. Good general account of mollusks. Corron, B. C. and F. K. Goprrey 1938-40: The Molluscs of South Australia. Pt. 1, The Pelecypoda; pt. 2, The Scaphopoda, Cephalopoda and Crepipoda. 600 pp., 589 figs. Government Publ., Adelaide. About $3.00. Excellent and well illustrated. Epmonpson, C. H. 1946: Reef and Shore Fauna of Hawaii. 381 pp., 223 figs. B. P. Bishop Museum, Honolulu. 100 pp. and 75 figs. on mollusks. Hirass, S. and Isao Taxi 1951: A Handbook of Illustrated Shells from the Jap- anese Islands and their Adjacent Terr. 134 pls. (130 in color). About $5.00. Bunkyokaku Publ., Tokyo. Excellent. Pratt, R. 1949: Shells Take You Over World Horizons. 50 pp., 32 color plates. National Geographic Magazine, Wash., D.C. July 1949 issue. Separates 50 cents. Out of print (1952). Excellent illustrations. Powe tt, A. W. B. 1946: The Shellfish of New Zealand. 2nd ed. 106 pp., 26 pls. (1 in color). Whitcombe and Tombs Ltd., Auckland. Complete checklist and illustrations of common species. Excellent. Rocers, Jutta 1951: The Shell Book. 485 pp., 87 pls. (8 in color). C. T. Bran- ford, Boston. A reprint of the 1908 edition with the names brought up-to- date in an appendix by Harald A. Rehder. $6.50. Excellent for beginners. SmitH, MaxweE Lt 1940: World-wide Sea Shells. 139 pp., many drawings. $4.50. Obtained from author, Box 65, Winter Park, Florida. Tinker, S. W. 1952: Pacific Sea Shells. 237 pp., illust. Paper covered: $2.75. Honolulu, T.H. Mainly gastropods of Hawaii. VerriLL, A. H. 1936: Strange Sea Shells and their Stories. 211 pp., figs., 5 pls. (1 in color). L. C. Page, Boston. $2.50. For children. 492 American Seashells VerriLL, A. H. 1950: The Shell Collectors Handbook. 228 pp., illus. Putnam’s, N.Y. $4.00. Wess, W. F. 1948: Handbook for Shell Collectors. 8th ed., 236 pp., about 1000 species figured. Interesting notes. $5.00. Obtained from author: 2515 Second Ave. N., St. Petersburg, Florida. East Coast of America Avpricu, B. D. E. and E. Snyper 1936: Florida Sea Shells. 126 pp., 11 pls. Houghton Mifflin, Boston. $1.25. About 150 species included. ARNOLD, AuGusTA 1903: The Sea Beach at Ebb-Tide. 470 pp., 600 figs. Century, N.Y. Second-hand, $3.00 to $5.00. Section on mollusks included, but out- of-date. Morris, P. A. 1939: What Shell Is That? 198 pp., 175 figs. Appleton-Century, N.Y. $2.25. Small pocket guide for New England collectors. Morris, P. A. 1951: A Field Guide to the Shells of Our Atlantic and Gulf Coasts. 2nd ed. 236 pp., 45 pls. (8 in color). Houghton Mifflin, Boston. $3.75. Names somewhat out-of-date. Perry, Loutse 1940: Marine Shells of the Southwest Coast of Florida. 260 pp., 39 pls. Paleontological Research Inst., Ithaca, N.Y. $3.50. Mostly shells of Sanibel Island. Well illustrated, good descriptions. For amateurs and advanced students. SMITH, MAxweELL 1937: East Coast Marine Shells. 308 pp., illus. Obtained from author, Box 65, Winter Park, Fla. $5.00. Names out-of-date. Viras, C. N. and N. R. Viras 1945: Florida Marine Shells. 151 pp., 12 color plates. C. N. Vilas Publ., Box 108, Sarasota, Florida. $2.75. For beginners; names somewhat out-of-date. West Coast of America Keep, J. and J. L. Batty, Jr. 1935: West Coast Shells. 350 pp., 334 text figs. Stanford University Press, Calif. $3.75. Morris, P. A. 1952: A Field Guide to Shells of the Pacific Coast and Hawaii. 220 pp., illus. Houghton Mifflin, Boston. $3.75. Recommended only for the part concerning our Pacific Coast. SmMitH, Maxwe.i 1944: Panama Marine Shells. 127 pp., illus. Obtained from author, Box 65, Winter Park, Fla. $6.00. Directories and U.S. Journals Directory of Conchologists. An American and international list of over 900 people interested in mollusks. Gives addresses, interests and exchange activi- ties. Mimeographed. Obtained from: Mr. John Q. Burch, 1584 West Ver- non Ave., Los Angeles 37, Calif. $1.50. Annual Report of the American Malacological Union. Names and addresses of over 350 active members, Obtained from: Secretary, The American Mala- cological Union, Buffalo Museum of Science, Buffalo 11, N.Y. The Nautilus, a quarterly devoted to the interests of conchologists. Technical and semi-popular articles, notes and news. $2.50 per year; quarterly. Dr. H. B. Baker, Bus. Mer., Zool. Lab., University of Pennsylvania, Philadelphia ity Je. Guide to the Molluscan Literature 493 Jobnsonia. Monographs of the Marine Mollusca of the Western Atlantic (quarto size). W. J. Clench, ed. Museum Comparative Zodlogy, Harvard Univ., Cambridge 38, Mass. $4.00 per year or per 100 pp. Excellent illus., descrip- tions, ranges, collecting localities, book reviews, etc. Occasional Papers on Mollusks. Depart. of Mollusks, Museum Comparative Zo- ology, Harvard Univ., Cambridge 38, Mass. Revisions, bio-bibliographies, medical snails, catalogs and other useful articles. Price list from W. J. Clench, ed. Leaflets in Malacology. S. Stillman Berry, ed., Redlands, Calif. Useful and in- teresting articles, dealing mainly with the Eastern Pacific fauna. Revista de la Sociedad Malacologica “Carlos de la Torre,” Univ. Habana, Cuba. C. G. Aguayo, ed. Technical articles of importance in English and Spanish. Current foreign journals are: Proceedings of the Malacological Society of London; Journal of Conchology (Great Britain); Archiv fiir Molluskenkunde (Frank- furt-am-Main); Journal de Conchyliologie (Paris); Proceedings Malacological Society of Japan (formerly the Venus), Basteria (Leiden), CHAPTER I—MAN AND MOLLUSKS Mollusks and Medicine in World War II. R. Tucker Axpportr. 1948. Smithsonian Ann. Report for 1947, pp. 325-338, 3 pls. (no. 3933). Snail Invaders. R. Tucker Assotr. Natural History Magazine (N.Y.), Feb. 1950, vol. 59, pp. 80-85, 13 figs. The Venomous Cone Shells. R. Tucker Appotr. 1950. The Science Counselor (Duquesne Univ.), Dec. 1950, pp. 125-126; 153, 3 pls. Molluscan Species in Californian Shell Middens. R. E. Grrenco. 1951. Report 13, Univ. Calif. Archaeol. Survey, pp. 1-23. Good bibliography. The Geographical Distribution of the Shell-Purple Industry. J. W. Jackson. 1916. Memoirs and Proc. Manchester Literary and Philos. Soc., vol. 60, pt. 2, no. 7, 29 pp., map. The Use of Cowry-Shells for the Purposes of Currency, Amulets and Charms. J. W. Jackson. 1916. Ibid., vol. 60, pt. 3, 72 pp., maps. Shell Trumpets and Their Distribution in the Old and New World. J. W. Jackson. 1916. [bid., vol. 60, pt. 2, no. 8, 22 pp. The Geographic Distribution of the Use of Pearls and Pearl-Shell. J. W. Jackson. 1916. Ibid., vol. 60, pt. 3, no. 12, 53 pp. Mémoire sur la Pourpre. H. Lacaze-Dutuirrs. 1859. Annales des Science Natu- relles (Zoologique), 4th series, vol. 12, pp. 5-84, 2 pls. Ethno-Conchology: A Study of Primitive Money. R. E. C. Stearns. 1889. Annual Report U.S. Nat. Mus. for 1886-87, pp. 297-334, 9 pls. (Out of rint). The Use of Marine Mollusca and Their Value in Reconstructing Prehistoric Trade Routes in the American Southwest. D. B. Tower. 1945. Papers Exca- vators Club (Cambridge, Mass.), vol. 2, no. 3, pp. 1-54. Illus. European Ballast Shells in Staten Island, N.Y. M. P. WEINGARTNER. 1951. The Nautilus, vol. 65, p. 132. Trade Marks. W. W. Wiccrnton. 1946. The Shell Magazine (Asiatic Petroleum Co.), London, vol. 26, no. 480, Dec., pp. 322-324. Also see the Jubilee Pam- phlet of the “Shell” Transport and Trading Co., Ltd. (London), 1947, 26 pp., illus. 494 American Seashells CHAPTER II—LIFE OF THE SNAIL Habits, Life Histories and Ecology A Preliminary Investigation of the Importance of Desiccation, Temperature and Salinity as Factors Controlling the Vertical Distribution of Certain Intertidal Marine Gastropods in False Bay, South Africa. G. J. BRozEKHUYSEN. 1940. Trans. Royal Soc. South Africa, vol. 28, pt. 3, pp. 278-292, 2 pls. Notes on the Louisiana Conch, Thais haemastoma in its Relation to the Oyster, Ostrea virginica. M. D, BurKENRoAD. 1931. Ecology, vol. 12, no. 4, pp. 656- 664, 2 figs. Observations on the Local Movements of Littorina littorea (L.) and Thais lapil- lus (L.). R. W. Dexter. The Nautilus, vol. 57, pp. 6-8. The Mud Snail: Nassa obsoleta. A. C. Drwon. 1905. Cold Spring Harbor Monogr. 5, pp. 1-48, 2 pls. (Habits and anatomy). The Mechanism of Locomotion in Gastropod Molluscs. H. W. LissMANN. 1945. Journ. Exper. Biol., vol. 21, pp. 58-69. Illus. The Biology of Purpura lapillus. H. B. Moore. 1936-39. Pts. I, I, and III. Journ. Marine Biol. Assoc., vol. 21, pp. 61-89; vol. 23, pp. 57-74. The Leaping of the Stromb (Strombus gigas Linn.). G. H. Parker. 1922. Journ. Exper. Zool., vol. 36, no. 2, pp. 205-209, 2 figs. Biology of Acmaea testudinalis Muller. M. A. Wittcox. 1905. Amer. Nat., vol. 39, NO. 461, Pp. 325-333. Growth and Feeding Influence of Natural and Experimental Conditions in Determining Shape of Shell and Rate of Growth in Gastropods of the Genus Crepidula. W. R. Coe. 1942. Journ. Morph., vol. 71, no. 1, pp. 35-47. A Statistical Test of the Species Concept in Littorina. J. CoLMAN. 1932. Biol. Bull., vol. 62, no. 3, pp. 223-243, 11 figs., 8 tables. How Fulgar and Sycotypus Eat Oysters, Mussels and Clams (Busycon). H. S. Cotton. 1908. Proc. Acad. Nat. Sci. Phila., 1908, pp. 3-10, 5 pls. Growth of the Oyster Drill, Urosalpinx cinerea, Feeding on Four Different Food Animals. J. B. ENGLE. 1942. Anatom. Records, vol. 84, p. 505ff. Observations on Some of the Probable Factors Controlling the Size of Certain Tide Pool Snails. R. R. Humpurey and R. W. Macey. 1930. Publ. Puget Sound Biol. Sta., vol. 7, pp. 205-208. The Mode of Feeding of Crepidula ... J. H. Orton. 1912. Journ. Mar. Biol. Assoc., vol. 9, no. 3, pp. 444-478. Illus. Anatomy The Structure and Function of the Alimentary Canal of Some Tectibranch Molluscs with a Note on Excretion. Vera Frerrer. 1939. Trans. Royal Soc. Edinburgh, vol. 59, pt. 3, no. 22, pp. 599-646. Excellent figs.; also same subject on Chitons vol. 59, p. 119ff; on Limpets vol. 57, p. 287ff; on Aeolids vol. 59, p. 267ff. Guide to the Molluscan Literature 495 The Anatomy of the Gastropod Crepidula adunca Sowerby. C. E. Moritz. 1938. Univ. Calif. Publ. Zool., vol. 43, no. 5, pp. 83-92, 6 figs. The Anatomy of Acmaea testudinalis Muller. M. A. Witicox. 1906. Amer. Nat., vol. 40, pp. 171-187, 4 figs. (External anatomy.) The Prosobranchiate Mollusca; A Functional Interpretation of Their Structure and Evolution. C. M. Yonce. 1939. Philos. Trans. Royal Soc. London, ser. B, no. 566, vol. 230, pp. 79-147. Illus. Reproduction and Development Sexual Differentiation in Mollusks. W. R. Cor. 1943-44. Quart. Review Biology, vol. 18, pp. 154-164; vol. 19, pp. 85-97. Large bibliography. Sur le Dimorphism Sexual des Coquilles. Ep. Lamy. 1937. Journ. de Conchyl., vol. 81, pp. 283-301. Illus. Reproduction and Larval Development of Danish Marine Bottom Inverte- brates. ... Gunnar THorson. 1946. Medd. Komm. Danmarks Fisk.-Ha- vund. Series on Plankton, vol. 4, no. 1, pp. 1-523. (34 pp. of bibliography.) The Embryology of Fulgur: A Study of the Influence of Yolk on Development. E. G. Conkin. 1907. Proc. Acad. Nat. Sci. Phila. 1907, pp. 321-358, 6 pls. The Development of a Mollusk. B. E. Daureren. 1906. Amer. Mus. Journ., vol. 6, pp. 28-53. (Illus. of models.) Early Development of Haminea. R. E. Leonarp. 1918. Publ. Puget Sound Biol. Sta., vol. 2, no. 34, pp. 45-63, 5 pls. The Embryology of Patella. W. Patren. 1885. Arbeit. Zoolog. Inst., Wien, vol. 6, pp. 149-174, 5 pls. Egg-Cases and Larvae The Egg Capsules of Certain Neritidae. E. A. ANprews. 1935. Journ. Morph., VOI! 57, MO. <1, Pps 31-54, 3) pls. Egg Capsules and Development of Some Marine Prosobranchs from Tropical West Africa. J. KNupsEN. 1950. Atlantide Report (Copenhagen), no. 1, pp. 85-130. (Large bibliography.) The Eggs and Larvae of Some Prosobranchs from Bermuda. M. V. Lesour. 1945. Proc. Zool. Soc. London, vol. 114, pp. 462-489, 43 text-figs. Biologie et Ponte de Mollusques Gastéropodes Néo-Calédoniens. J. Rispec. 1935. Bull. Soc. Zool. de France, vol. 60, pp. 387-417. Illus. Spawning of the Whelk [Busycon canaliculata]. L. B. Spencer. 1910. Zool. Soc. Bull., N.Y., no. 38, pp. 637-638. (Two photos of process.) Studies on the Egg-Capsules and Development of Arctic Marine Prosobranchs. Gunnar Tuorson. 1935. Komm. Vidensk. Undersog. Gronland, vol. 100, no. 5, pp. 5-71. 75 figs. Studies on the Egg Masses and Larval Development of Gastropoda from the Iranian Gulf. Gunnar Tuorson. 1940. Danish Sci. Invest. in Iran, pt. 2, pp. 159-238, 32 figs. Spawning of Fulgur perversus [Busycon contrarium]. J. Witicox. 1885. Proc. Acad. Nat. Sci., Phila., 1885, pp. 119-120. 496 American Seashells CHAPTER UI—LIFE OF THE CLAM An Annotated Bibliography of Oysters, with Pertinent Material on Mussels and Other Shellfish. J. L. BauGHMaAN. 1948. Texas A. and M. Research Founda- tion. pp. 1-794. Over 2000 articles on the biology of mollusks are listed, with abstracts and a subject index. Very useful. Habits, Life Histories and Ecology The Habits of Life of Some West Coast Bivalves. Frirz Haas. 1942. The Nauti- lus, vol. 55, pp. 109-113 (Lithophaga, Diplodonta and Cooperella), ibid., vol. 56, pp. 30-33 (Mytilus and Brachidontes). The Life History and Growth of the Razor Clam. H. C. McMILin. 1924. Wash. State Dept. Fish., 52 pp., 5 pls., 3 graphs. The Pismo Clam: Further Studies of Its Life History and Depletion. W. C. HERRINGTON. 1930. Calif. State Fish Lab. Contrib. no. 81, Bull. 18, 67 pp., 16 figs. Notes es Ecology of the Butter Clam, Saxidomus giganteus Deshays. C. M. Fraser. 1928. Lrans. Royal Soc. Canada, ser. 3, vol. 22, pp. 271-277, 2 pls., 7 tables; also see ibid., vol. 22, pp. 249-270 for Paphia staminea; also vol. 25, p- 59-72 for “Cardium corbis.” The Edible Bivalves of California. Paut Bonnor. 1940. Calif. Fish and Game, vol. 26, no. 3, pp. 212-239. Notes, habits, sketches, and laws pertaining to catches. A Resurgent Population of the California Bay-Mussel (Mytilus edulis diegensis). W. R. Cor. 1946. Journ. Morph., vol. 78, no. 1, pp. 85-104. The Marine Borers of the San Francisco Bay Region. C. A. Koromw. 1921. Re- port San Francisco Bay Marine Piling Survey, pp. 23-61. A Brief Study of the Succession of Clams on a Marine Terrace. Paut T. WItson. 1926. Publ. Puget Sound Biol. Sta., vol. 5, pp. 137-148. The Habits and Movements of the Razor-Shell Clam, Ensis directus Con. G. A. Drew. 1907. Biol. Bull., vol. 12, no. 3, pp. 127-140, 1 pl. Locomotion in Solenomya and Its Relatives. G. A. Drew. 1900. Anat. Anzeiger, vol. 17, no. 15, pp. 257-266, 12 figs. The Structure and Behaviour of “Hiatella gallicana” (Lamarck) and “H. arctica” (L.), with Special Reference to the Boring Habit. W. R. HunrTer. 1949. Proc, Royal Soc, Edinburgh, B, vol. 63, pt. 3, no. 19, pp. 271-289. 12 figs. Growth and Feeding The Life-History and Growth of the Pismo Clam (Tivela stultorum Mawe). F. W. WeEyMouTH. 1923. Bull. 7, Calif. State Fish and Game Comm., pp. 5-120. The Age and Growth of the Pacific Cockle (Cardium corbis). F. W. WreymMouTH and S. H. THompson. 1931. Bureau of Fisheries Doc. no. 1101 (Wash., D.C.), pp. 633-641. (also see Doc. nos. 984, 1099 and 1100). Food Material as a Factor in Growth Rate of Some Pacific Clams. G. M. Smirn. 1928. Trans. Royal Soc. Canada, ser. 3, vol. 22, sec. 5, pp. 287-292. (see also Further Observations. . . . ibid., 1933, vol. 27, sec. 5, pp. 229-245). Guide to the Molluscan Literature 497 The Mechanism of Feeding, Digestion, and Assimilation in the Lamellibranch Mya. C. M. Yonce. 1923. Brit. Jour. Exper. Biol., vol. 1, pp. 15-63, 27 figs. On the Morphology, Feeding Mechanisms, and Digestion of Ensis siliqua (Schu- Se A. GRAHAM. 1931. Trans. Royal Soc. Edinburgh, vol. 56, pp. 725- 751, 8 figs. The Base an Food of the California Sea Mussel. D. L. Fox et al. 1936. Bull. Scripps Inst. Oceanogr. Univ. G@alitlicch. ser... vol. 4, no: 1, pp. 1-64. The Systematic Value of a Study of Molluscan Faeces. H. B. Moore. 1931. Proc, Malacological Soc. London, vol. 19, pp. 281-291, 4 pls. Anatomy and Shell Structure The Anatomy of Some Protobranch Mollusks. Harorp Heatu. 1937. Mem. Mus. Royal d’Hist. Nat. Belgique, ser. 2, fasc. 10, pp. 3-25, 10 pls. The Anatomy of the Pelecypod Family Arcidae. Harorp Heatu. 1941. Trans. Amer, Philos Soc, (u.s.).) Vol. 31, pt. 5, pp./287-319, 22) pls. Uber die Anatomie von Chama pellucida Broderip. E. Grirsrr. 1913. Zool. Jabrb. Suppl., vol. 13, pp. 207-280, 1 pl., 11 figs. Literature on the Shell Structure of Pelecypods. H. G. ScHENcK. 1934. Bull. Mus. Royal d’hist. Nat. Belgique, vol. 10, no. 34, pp. 1-20. The Structure and Composition of the Shell of Tellina tenuis. E. R. TRUEMAN. 1942. Journ. Royal Micro. Soc., vol. 62, pp. 69-92. The Shell Structure of the Mollusks. O. B. Boggild. i930. D. Kgl. Danske Vidensk. Selsk. Skrifter, Naturv. Og Mathem., Afd. 9, Raekke II.2., pp. 233- 326, 10 figs., 15 pls. The Pigmentation of Molluscan Shells. Atex Comrort. 1951. Biol. Reviews Cambridge Philos. Soc., vol. 26, no. 3, pp. 285-301. 5 figs. The Mystery of the Pearl. J. Borman. 1941. Internat. Archiv. Ethnographie, Leiden, suppl. to vol. 39, pp. 1-170, 37 pls. [Excellent semi-popular account in English. | Reproduction, Development and Larvae Sexual Differentiation in Mollusks. W.R. Cor. 1943. Quart. Review of Biology, vol. 18, pp. 154-164; also vol. 19, pp. 85-97. Large bibliography. Development of the Oyster. W. K. Brooks. 1880. Studies Biol. Lab., Johns Hop- kins Univ., vol. 4, pp. 1-93, 10 pls. Spawning Habits of the Mussel, Mytilus californianus Conrad, with Notes on the Possible Relation to Mussel Poison. W. W. Forest. 1936. Univ. Calif. Publ. Zool., vol. 41, no. 5, pp. 35-44, pl. 3. Reproduction and Larval Ecology of Marine Bottom Invertebrates. G. THorson. 1950. Biol. Reviews, London, vol. 25, pp. 1-45. Large bibliography. Relations Between the Moon and Periodicity in the Breeding of Marine Animals. P. Korrinea. 1947. Ecol. Monogr., Durham, N.C., vol. 17, no. 3, pp. 347- 381 (Ostrea, Littorina, Mytilus and Pacten). The Identification and Classification of Lamellibranch Larvae. C. B. Rees. 1950. Hull Bull. Mar. Ecol., vol. 3, no. 19, pp. 73-104, figs. Bivalve Larvae of Malpeque Bay, P. E. I. M. C. Sutrivan. 1948. Bull. 77, Fish. Research Board Canada, pp. 1-36, 22 pls. 498 American Seashells CHAPTER IV—LIVES OF THE OTHER MOLLUSKS Cephalopoda The Biology of Spirula spirula L. A. F. Brunn. 1943. Dana Report (Copen- hagen), vol. 4, pt. 24, pp. 1-44, 13 figs., 2 pls. Sexual Activities of the Squid, Loligo pealii (Les). I Copulation, Egglaying and Fertilization. G. A. Drew. 1911. Journ. Morph., vol. 22, pp. 327-359, pls. 1-4; also 1919, vol. 32, pp. 379-435, 6 pls. The Anatomy of the Common Squid, Loligo pealii Lesueur. L. W. WiiiaMs. 1909. E. J. Brill, Leiden. 92 pp., 16 figs., 3 pls. Excellent. _ Report on the Cephalopods of the Northeastern Coast of America. A. E. VERRILL. 1882. Rep. U.S. Comm. Fish, pt. 7, for 1879, 245 pp., 47 pls. Amphineura On the Presence of Eyes in the Shells of Certain Chitonidae. H. N. Mosevey. 1885. Quart. Journ. Micro. Sct. (N.S.), vol. 25, pp. 2-26, 6 pls. Notes on the Post-larval Development of the Giant Chiton, Cryptochiton stelleri (Midd.). S. Oxupa. 1947. Journ. Facul. Sci., Hokkaido Univ., ser. 6, Zool., vol. 9, no. 3, pp. 267-275, 18 figs. Die Anatomie und Phylogenie der Chitonen. L. H. PLare. 1899. Fauna Chilensis (Jena), vol. 2, pp. 15-216, 9 pls. Excellent. Scaphopoda Scaphopoda. H. Simroru. 1892. In Bronn’s Thier-Reichs (Leipzig), vol. 4, pp: 356-467, 10 figs., 5 pls. (In German; with long bibliography.) A Monograph of the East American Scaphopod Mollusks. J. B. HENnpeErson. 1920. Bull. U.S. Nat. Museum, 111, pp. 1-177, pls. 1-20. Out of print. Generic and Subgeneric Names in the Molluscan Class Scaphopoda. W. K. Emerson. 1952. Jour. Wash. Acad. Sci., vol. 42, no. 9, pp. 296-303. CHAPTER V—COLLECTING AMERICAN SEASHELLS Night Collecting; The Bar; Digging "Em Out; and other articles. B. R. Bates. 1945-46. The Nautilus, vols. 58 and 59. Extremely interesting and informa- tive. Kalling and Preservation of Bivalve Larvae in Fluids. M. R. Carriker. 1950. The Nautilus, vol. 64, pp. 14-17. Instructions for Collecting Mollusks, and Other Useful Hints for the Con- chologist. W. H. Dari. 1892. Part G, Bull. U.S. Nat. Mus., no. 39, 55 pp. Out of print. The Collection and Preparation of Shells. T. C. SrepHens. 1946-47. Turtox News, vol. 24, no. 9 and vol. 25, no. 1, 15 pp. A rather full annotated list of references. Guide to the Molluscan Literature 499 Symposium on “Methods of Collecting and Preserving Mollusks.” Annual Report, American Malacological Union, 1941. Several authors. Excellent. Write: Secretary, A. M. U., Buffalo Museum of Science, Buffalo 11, N.Y. CHAPTER VI—HOW TO KNOW AMERICAN SEASHELLS Malacology and the Official List of Generic Names. C. G. Aguayo. 1949. The Nautilus, vol. 63, pp. 17-19. Illustrated Glossary of Gastropoda, Scaphopoda, Amphineura. Beatrice Burch. 1950. Minutes 105, Conch. Soc. Southern Calif. Mimeographed. $1.50. Pelecypoda glossary also available. Systematics and the Origin of Species. E. Mayr. 1942. Columbia Univ. Press, N.Y. 334 pp. Good bibliography. Procedure in Taxonomy. E. T. ScHenk and J. H. McMasrers. 1948. Stanford Univ. Press, Calif. Revised ed. by A. M. Keen and S. W. Muller. CrOCRAP IE SEG UT DE ATLANTIC COAST General List of Marine Mollusca of the Atlantic Coast from Labrador to Texas. C. W. Jounson. 1934. Proc. Boston Soc. Nat. Hist., vol. 40, pp. 1-204. 2632 species listed with ranges. About 75% complete, some names now obsolete. Bibli- ography very good, with over 500 entries. No illustrations or descriptions. Johnsonia. Monographs of the Marine Mollusca of the Western Atlantic. 1942- Vols. 1 and 2 (600 pp., quarto size now complete). Museum Comparative Zoology, Cambridge 38, Mass. Thorough treatment of various genera with excellent plates, descriptions, ranges, records and collecting localities. W. J. Clench, ed. A Preliminary Catalogue of the Shell-bearing Marine Mollusks and Brachiopods of the Southeastern Coast of the United States. W. H. Dati. 1889 (and a 1903 reprint). Bull. 37, U. S. Nat. Mus., 232 pp., 45 pls. Illustrations very useful, ranges fairly good, but the names out-of-date. Out of print. Blake Reports. Reports on the Results of the Dredging ... in the Gulf of Mexico and the Caribbean Sea by the .. . Steamer ‘Blake’. 1886. Pt. I. Brachiopoda and Pelecypoda. W. H. Dati. Bull. Mus. Comp. Zool., vol. 12, pp. 171-318, 9 pls.; 1889, Pt. Il, Gastropoda and Scaphopoda. [bid., vol. 18, pp. 1-492, 30 pls. Numerous deep-sea species with excellent drawings. Contributions to the Tertiary Fauna of Florida. W. H. Dati. 1890-1903. 6 parts. Trans. Wagner Inst., vol. 3, 1654 pp., 60 pls. A monumental work containing many important revisions. Contains many recent species, but the nomen- clature is out-of-date. 500 American Seashells Greenland, Labrador and Newfoundland Mollusca of the Crocker Land Expedition to Northwest Greenland and Grinnel Land. F. C. Baker. 1919. Bull. Amer. Mus. Nat. Hist., vol. 41, pp. 479-517. Report on the Mollusks Collected by L. M. ‘Turner at Ungava Bay, North Labra- dor. W. H. Dati. 1886. Proc. U.S. Nat. Mus., vol. 9, pp. 202-208, 3 figs. Observations . . . Recent Invertebrate Fauna of Labrador. A. S. Packarb. 1867. Mem. Boston Soc. Nat. Hist., vol. 1, pp. 210-303, pl. 7-8. A List of the Mollusks Collected by O. Bryant along the Coasts of Labrador, Newfoundland and Nova Scotia. C. W. JoHNson. 1926. The Nautilus, vol. 39, pp. 128-135, and vol. 4o, pp. 21-25. Eastern Canada The Mollusca of Nova Scotia. J. M. Jones. 1877. Proc. Trans. Nova Scotian Inst. Nat. Hist., vol. 4, pp. 321-330. Catalogue of the Marine Invertebrates of Eastern Canada. J. F. Whiteaves. 1901. 272 pp. Ottawa: Geol. Survey of Canada. Bivalve Larvae of Malpeque Bay, Prince Edward Island. Bull. 77, Fish. Research Board Canada, pp. 1-36, 22 pls. M. C. SuLrivan. 1948. New England Report on the Invertebrata of Massachusetts. Second ed. 1870. A. A. GouLp. W. G. Binney, ed. 524 pp., 755 fig., 27 pls. Mollusca. Boston: Wright and Potter, State Printers. Fauna of New England. List of the Mollusca. C. W. JoHNson. 1915. Occas. Papers, Boston Soc. Nat. Hist., vol. 7, no. 13, pp. 1-231. Plankton of the Offshore Waters of the Gulf of Maine. H. B. BiceLow. 1926. Bull. U.S. Bur. Fish., vol. 40, pp. 1-509, figs. 1-134. List of Shell-bearing Mollusca of Frenchman’s Bay, Maine. D. BLANry. 1906. Proc. Boston Soc. Nat. Hist., vol. 32, pp. 23-41, pl. 1. Preliminary Catalogue of the Marine Invertebrata of Casco Bay, Maine. J. S. Kinestey. 1go1. Proc. Portland Soc. Nat. Hist., vol. 2, pp. 159-183. A Bibliography of the Recent Mollusca of Maine—1605-1930. N. W. LermMonp and A. H. Norton. 1930. Maine Nat., vol. 10, pp. 49-73; 100-121. Shells of Maine, A Catalogue. N. W. Lermonp. 1909. State Entomol. of Maine, Ann. Report 4, pp. 25-70. Report Upon the Invertebrate Animals of Vineyard Sound . . . Mollusca. A. E. VeERRILL. 1873. Moll. Rep. U.S. Fish Comm., vol. 1, pp. 634-698, pls. 20-32. (Also numerous similar reports by same author in Trans. Conn. Acad.) Notes on the Marine Mollusks of Cape Ann, Mass. R. W. DexTER. 1942. The Nautilus, vol. 56, pp. 57-61. Good list. See also ibid., vol. 58, pp. 18-24; 135- 142. The Shell-bearing Mollusca of Rhode Island. H. F. Carpenter. 1884-1902. Nu- merous articles by this title in The Nautilus, vols. 1-16. Marine Mollusca of the Bridgeport, Conn. Region. A. P. Jacor. 1924. The Nauti- lus, vol. 38, pp. 49-51. Molluscan Fauna of New Haven. G. W. Perkins. 1869. Proc. Boston Soc. Nat. Hist., vol. 13, pp. 109-164. Guide to the Molluscan Literature 501 New York Check List of the Mollusca of New York. E. J. Lerson. 1905. Bull. N.Y. State Museum, vol. 88, pp. 1-112. Some Marine Mollusca about New York City. A. P. Jacor. 1919. The Nautilus, vol. 32, pp. 90-94; vol. 34, pp- 59-60. List of Marine Mollusca of Coldspring Harbor, Long Island. F. N. Batcu. 1899. Proc. Boston Soc. Nat. Hist., vol. 29, pp. 133-162, pl. 1. On the Mollusca of Peconic and Gardiner’s Bays, Long Island, N.Y. S. Smiru. 1860. Ann. Lyceum Nat. Hist. N.Y., vol. 7, pp. 147-168; also vol. 9, pp. 377- 407, 6 figs. Maryland and Virginia Recent Oyster Researches on Chesapeake Bay in Maryland. R. V. TRurttT. 1931. Report Chesapeake Biol. Lab. 1931, pp. 1-28. Littoral Marine Mollusks of Chincoteague Island, Virginia. J. B. HENDERSON and P. Bartscu. 1914. Proc. U.S. Nat. Mus., vol. 47, pp. 411-421, 2 pls. Out of print. Oyster Bars of the Potomac River. D. G. Frey. 1946. Fish and Wildlife Service, Special Sci. Report, 32, pp. 1-93, mimeo. List of Mollusks. North and South Carolina Additions to the Shallow-water Mollusca of Cape Hatteras, N. C., dredged by the . . . Albatross in 1883-84. K. J. BusH. 1885. Trans. Conn. Acad. Arts Sci., vol. 6, pp. 453-480, illus. List of Mollusca from around Beaufort, N. Carolina, with Notes on Tethys. A. G. Hackney. 1944. The Nautilus, vol. 58, pp. 56-64. 174 marine species listed with habitats. Notes on the Natural History of Fort Macon, N.C., and Vicinity. E. Cougs. 1871. Proc. Acad. Nat. Sci. Phila. for 1871, pp. 120-148; and ibid. for 1878, PP: 297-315. Some Marine Molluscan Shells of Beaufort and Vicinity. A. P. Jacor. 1921. Journ. Elisha Mitchell Sci. Soc., vol. 36, pp. 129-145, pls. 11-13. Catalog of Mollusca of South Carolina. W. G. Maz¥cx. 1913. Contrib. Charles- ton Mus., 2, xvi-39 pp. Florida Marine Shells of the Southwest Coast of Florida. Loutsr Perry. 1940. Bull. Paleontol. Research Inst., Ithaca, N.Y. 260 pp., 39 excellent plates. Catalogue of the Marine Shells of Florida, with Notes and Descriptions of Several New Species. W. W. Carkins. 1878. Proc. Davenport Acad. Nat. Sci., vol. 2, pp: 232-252, 1 pl: An Annotated List of the Shells of St. Augustine, Fla. C. W. JoHNson. 1890. The Nautilus, vol. 3, pp. 103-105. List of Mollusca Obtained in South Carolina and Florida in 1871-72. J. C. Met- VILLE. 1881. Journal of Conchology (Great Britain), vol. 3, pp. 155-173. 502 American Seashells Mass Mortality of Marine Animals on the Lower West Coast of Florida, Nov. 1946 to Jan. 1947. Gorpon GunTER et al. Science, vol. 105, pp. 256-257. Numerous articles on Florida mollusks appear in The Nautilus. Gulf States Recent Molluscs of the Gulf of Mexico, and Pleistocene and Pliocene Species from the Gulf States. C. J. Maury. 1920-22. Bull. Amer. Paleont., vol. 8, No. 34, pp. 1-115; vol. 9, no. 38, pp. 34-142. Some New and Interesting Mollusks from the Deeper Waters of the Gulf of Mexico. H. A. ReHper and R. T. Aszpotr. 1951. Revista Soc. Malac. “C. dea: Worre; vol. 8, no. 2, pp..53-66, 2 pls. A Contribution to the Fauna of the Coast of Louisiana. L. R. Cary. 1906. Gulf Biol. Sta., Louisiana Bull., vol. 6, pp. 50-59. Pteropoda from Louisiana. M. D, Burkenroap. 1933. The Nautilus, vol. 47, - 94°57. Be hanatce and Marine Assemblages of the Texas Coast, with Special Refer- ence to Mollusks. H. S. Lapp. 1951. Publ. Inst. Marine Sci. Texas, vol. 2, no. I, pp. 129-163, tables, maps. Notes on the Marine Shells of the Texas Coast. J. K. Srrecker. 1935. Baylor Bull., vol. 38, no. 3, pp. 48-60. Mollusks from Point Isabel in Texas. H. B. SteNzEL. 1940. The Nautilus, vol. 54, pp. 20-21 (list only). An Illustrated Check List of the Marine Mollusks of Texas. T. E. PuLLEy. 1952. Texas Jour, Science, vol. 4, no. 2, pp. 167-199, 13 pls. PACIFIC COAST General An Abridged Check List and Bibliography of West North American Marine Mollusca. A. Myra Kren. 1937. Stanford Univ. Press, 87 pp. Very valuable paper with a useful bibliography. Catalogue of the Marine Pliocene and Pleistocene Mollusca of California and Adjacent Regions. U.S. Grant, 1v and H. R. Gare. 1931. Mem. San Diego Soc. Nat. Hist., vol. 1, 1036 pp., 32 pls. The Marine Shells of the West Coast of North America. Ipa S. OLDRoyp. 1924- 1927. Stanford Univ. Publ., Univ. Ser., Geol. Sci., vol. 1 (1924), Pelecypoda and Brachiopoda, 248 pp., 57 pls.; vol. 2, Gastropoda, Scaphopoda and Am- phineura. Pt. 1, 298 pp., 29 pls.; Pt. 2, 304 pp., 42 pls.; Pt. 3, 340 pp., 35 pls. A compilation of original descriptions. Illustrations recommended with the corrections given by A. Myra Keen; see above. Summary of the Marine Shell-bearing Mollusks of the Northwest Coast of America, from San Diego, California, to the: Polar'Sea... . .; W. Hi DArr: 1921. Bull. 112, U.S. Nat. Mus., 217 pp., 22 pls. Good bibliography and illustrations. Names out-of-date. Ranges since extended. Illustrated Key to West North American Pelecypod Genera. A. M. KEEN and D. Frizzeiy. 1946 ed. Stanford Univ. Press. 28 pp., illus. Very helpful. Guide to the Molluscan Literature 503 Illustrated Key to West North American Gastropod Genera. A. M. Kren and J. C. Pearson. 1952. Stanford Univ. Press. 39 pp., illus. Rather helpful, with useful pen drawings. Mollusks from the West Coast of Mexico and Central America. L. G. HEerTLein and A. M. Srrone. 1940-50. Pts. 1 to 10. Zoologica (N.Y. Zool. Soc.), vols. 25 to 36. Very useful for more southern species. Distributional List of the West American Marine Mollusks. By numerous au- thors; edited by Joun Q. Burcu. Proc. Conch. Club Southern Calif. 1945- 46. Mimeographed. Very valuable, with up-to-date names, locality records, habits, some identification hints and drawings. Alaska Marine Shells of Drier Bay, Knight Island, Prince William Sound, Alaska. W. J. EYERDAM. 1924. The Nautilus, vol. 38, pp. 22-28. Shell Collecting in Puget Sound and Alaska. Frep Baker. 1910. The Nautilus, vol. 24, pp. 25-31. Notes on the Mollusca of Forrester Island, Alaska. G. WiLtetr. 1918. The Nautilus, vol. 32, pp. 65-69; ibid., vol. 33, pp. 21-28. British Columbia Notes on the Marine Mollusca of the Pacific Coast of Canada. G. W. Taytor. 1899. Trans. Royal Soc. Canada, ser. 2, vol. 5, sec. 4, pp. 233-250; see also ibid., 1895, vol. 1, pp. 17-100. Report on the Marine Shells of British Columbia. C. F. Newcomer. 1893. Bull. Nat. Hist. Soc. Brit. Col., pp. 31-72. On Some Marine Invertebrata from the Queen Charlotte Islands. J. F. WuItTEAvEs. 1880, Geol. Survey Canada, Report of Progress, 1878-79, pp. 190B-205B. Washington Marine Shells of Puget Sound and Vicinity. Ipa S. OLpRoyp. 1924. Puget Sound Biol. Sta., Univ. Wash., vol. 4, Pp. 1-272, 49 pls. Oregon Edible Mollusca of the Oregon Coast. C. H. Epmonpson. 1920. Occas. Papers, B. P. Bishop Mus., Honolulu, vol. 7, no. 9, pp. 179-201, 6 figs. The Pelecypoda of the Coos Bay Region, Oregon. Yocum, H. B. and E. R. Epce. The Nautilus, vol. 43, pp. 49-51. 19209. An Index Method for Comparing Molluscan Faunules. H. G. Scuenck and Myra KEEN. 1937. Proc. Amer. Philos. Soc., vol. 77, pp. 161-182. California The Marine Molluscan Fauna from the Vicinity of Bolinas Bay, California. BRUCE L. Crark. 1914. The Nautilus, vol. 28, pp. 25-28. The Gastropod Fauna of the Intertidal Zone at Moss Beach, San Mateo Co., Calif. H. E. Vokes. 1936. The Nautilus, vol. 50, pp. 46-50. 504 American Seashells Molluscan Fauna from San Francisco Bay. E. L. Packarp. 1918. Univ. Calif. Publ. Zool., vol. 14, no. 2, pp. 199-452, pls. 14-60. Ecological Aspects of a California Marine Estuary. G. E. MacGrnirie. 1935. Amer. Midland Naturalist, vol. 16, no. 5, pp. 629-765. Partial List of the Molluscan Fauna of Catalina Island. A. M. Strona. 1923. The Nautilus, vol. 37, pp. 37-43. Mollusks of Anaheim Bay, California. E. P. Cnace. 1916. The Nautilus, vol. 29, . 129-131. The Meee Mollusks and Brachiopods of Monterey Bay, California, and Vicinity. A. G. SmitH and M. Gorpon. 1948. Proc. Calif. Acad. Sci., 4th ser., vol. 26, no. 8, pp. 147-245. Excellent and with a full bibliography of the region. Mollusks and Brachiopods Collected in San Diego, California. F. W. Ketsey. 1907. Trans. San Diego Soc. Nat. Hist., vol. 1, no. 2, pp. 31-55. Common Marine Bivalves of California. J. E. Frrcu. 1953. Calif. Fish Bull., no. 90, 102 pp., 63 figs. Excellent and reliable, ADDITIONAL REFERENCES Appott, R. Tucker 1955: Introducing Seashells. vi + 64 pp., 10 pls. (6 in color), text figs. D. Van Nostrand, N.Y. $2.50. A guide and introduction for beginners. American Matacorogicar Society 1955: How to Collect Shells. 50 pp. Buffalo Museum of Science, Buffalo 11, N.Y. $1.00. A very useful booklet compiled by numerous experts. Barnard, K. H. 1952: A Beginner's Guide to South African Shells. 215 pp., 5 color pls., numerous text figs. Maskew Miller Ltd., Cape Town. $3.00. GutseLi, J. S. 1931: Natural History of the Bay Scallop. 63 pp. Bulletin Bureau Fisheries, vol. 46 (Document no. 1100). Washington, DC. Vechnical: Hornevr, James 1951: Indian Molluscs. iv + 96 pp., 1 color pl., 70 text figs. Bombay Natural History Society, Apollo St., Bombay. $1.50. Excellent and interesting reading. Hurcuinson, W. M. 1954: A. Child’s Book of Sea Shells. 28 pp., illustrated in color. Maxton Publishers Inc., N.Y. 75 cents. Excellent for 7 to 9 year olds. Jounson, Myrtie FE. 1954: West Coast Marine Shells. 36 pp., 16 text figs. Natural History Museum, San Diego 1, Calif. 65 cents. A useful beginner’s booklet. Oxsson, A. A. and Anne Harsison 1953: Pliocene Mollusca of Southern Florida. viii + 457 pp., 65 pls. Academy Natural Sciences, Phila. 3, Pa. $8.00. Many living species included. Excellent plates. Perry, L. M. and J. S. Scoweneer 1955: Marine Shells of the Western Coast of Florida. 198 pp., 55 pls. Paleontological Research Institution, Ithaca, N.Y. $7.00, Very useful. Abalone Borer, 464 Abalone, Great Keyhole, 99, pl. 18a Abalone Jingle, see False Jingle Shell, 372 Abalones, species of, 92-94, pl. 2 Abbreviations of author names, 87 Abra Clams, species of, 437 _Academy Natural Sciences of Phila., 68 _Acrior Chiton, 321 Adams’ Baby-bubble, 275, pl. 26t Adams’ Miniature Ark, 344, fig. 26b Adams’ Miniature Cerith, 158, pl. 22t _Adams’ Spiny Margarite, 109, fig. 31h _ Adanson’s Pleurotomaria, 92, pl. 3e Adductor muscles, definition of, 81 Admete, Common Northern, 253, fig. 55a _ Affinis Tagelus, 440 _ Agate Chama, see Clear Jewel Box, 393 _ Age, of clams, 34 of snails, 21 _ Aguayo, C. G., 493 _ Alaskan Gaper, 450 _ Alphabet Cone, 260, pl. 14p _ Alternate Bittium, 155 Alternate Keyhole Limpet, see Cayenne, 96 Alternate Tellin, 427, pl. gon _ Amber Pen Shell, 360, pl. 27w American Malacological Union, 492 _ American Pelican’s Foot, 173, pl. 23 American Star-shell, 124, pl. 3] American Thorny Oyster, see Atlantic Thorny Oyster, 369 Amethyst Gem Clam, 418, pl. 38k; fig. 84 Amphissas, species of, 223-225 Ample Rough Mya, 454 Ancula, Atlantic, 306, pl. 15f Angel Wing, 460, fig. 94a habits of, 32 Index to Angel Wing, Campeche, 462, pl. 32t Angel Wing, Fallen, 461 Angel Wing, False, pl. 32z; fig. 94b Angular Triton, 195, pl. 5d Angulate Periwinkle, 133, pl. 19a Angulate Wentletrap, 164, pl. 22b Anthus Clam, see Florida Marsh Clam, 381 Antillarian Date, see Giant Date Mussel, 357 Antillean Lima, 370 Antillean Limpet, 106, pl. 17a Antillean Miter, 248 Antillean Nerite, 129, pl. 4c Antillean Scallop, 366, pl. 34g Antillean Trivia, 178 Antillean Tusk, 330 Aperture, definition of, 75, fig. 23 Apple Murex, 202, pl. 1o- Apple Seed (Erato), 176, pl. 20-0 Approximate Lucina, 387, fig. 78g Archaeology, 7 Arctic Barrel-bubble, 280, fig. 59a Arctic Cancellate Chiton, 312 Arctic Natica, 191, fig. 43b Arctic Paper-bubble, 277, fig. s9b Arctic Rock-borer, see Arctic Saxicave, 452 Arctic Rough Mya, 453 Arctic Saxicave, 452, fig. 92a Arctic Wedge Clam, 451, pl. 32r Arenes, species of, 122 Argonaut, see Paper Nautilus, 485 Arks, species of, 342-346 Arrow Dwarf Triton, 232, pl. 25x Astartes, species of, 375 Atlanta, Peron’s, 184, fig. 41 Atlantic Bay Scallop, 367, pl. 331 Atlantic Bittersweet, 348, pl. 27g Atlantic Bob-tailed Squid, 480, fig. 99d Atlantic Carrier-shell, 173, pl. 5b 505 Subject Matter and Common Names Common names not used in this book appear in italics and are followed by the modern usage. Atlantic Cleft Clam, 384 Atlantic Crenulate Nut Clam, 335 Atlantic Deep-sea Scallop, 365, pl. 33¢ Atlantic Deer Cowrie, 180, pl. 6 Atlantic Distorsio, 196, pl. 25aa Atlantic Dogwinkle, 214, pl. 25g Atlantic Flat Lepton, 395 Atlantic Gem Turret, 267, fig. 57¢ Atlantic Gray Cowrie, 180, pl. 6c Atlantic Grooved Macoma, 434, pl. 32y Atlantic Hairy Triton, 195, pl. 9-1 Atlantic Jackknife Clam, 443, pl. 30k Atlantic Left-handed Jewel Box, 393, pl. 37¢ Atlantic Long-finned Squid, 480, fig. 99a Atlantic Modulus, 151, fig. 38 Atlantic Nut Clam, 334, fig. 70a, b Atlantic Oval Squid, 482 Atlantic Oyster Drill, 212, fig. 47¢ Atlantic Partridge Tun, 199, pl. 9d Atlantic Pearl Oyster, 359, pl. 35¢ Atlantic Plate Limpet, 104, fig. 22b Atlantic Razor Clam, 442, pl. 30f Atlantic Ribbed Mussel, 351, pl. 28h Atlantic Rupellaria, 420, pl. 30e Atlantic Sanguin, 439, pl. god Atlantic Strawberry Cockle, 398, pl. 39m Atlantic Surf Clam, 446, pl. 32p Atlantic Thorny Oyster, 369, pl. 36b Atlantic Wing Oyster, 359, pl. 35d Atlantic Yellow Cowrie, 180, pl. 6a Augers, species of, 265-267 Austin’s Cone, 264 Author names, list of, 87 Awl Miniature Cerith, 157, pl. 19w Awning Clams, species of, 333 Axial, definition of, 76 Baby-bubbles, species of, 275 Baby’s Cradle, see Common Atlantic Slipper-shell, 170 506 Baby’s Ear (Sinum), 190, pl. 22s Baby’s Foot Print, see Common Jingle Shell, 372 Baby’s Teeth, see Tessellate Nerite, 128 Baer’s Buccinum, 226, pl. 24v Baily-shells, species of, 231 Baily’s Miniature Ark, 343 Baird’s Liotia, 121, pl. 17u Baird’s Spiny Margarite, 109, pl. 3c Baird’s Top-shell, 113, pl. 3-0 Bales, B. R., 50, 172, 460 Bales’ False Dial, 139 Ballast shells, 10 Balthic Macoma, 431, fig. 88g Band Shell, see Tulip Shells, 242 Banded Tulip, 242, pl. 13¢ Barbados Chink, see Barbados Keyhole Limpet, 100 Barbados Keyhole Limpet, 100, pl. 17f Barbados Miter, 249, pl. 26d Bark Semele, 435, pl. 29z Barratt’s Corbula, 458, fig. 93a Barrel-bubbles, species of, 280 Bartsch, Paul, 68, 491 Bartsch’s Shipworm, 467 Basket Cockle, see Nuttall’s Cockle, 403 Basket Shell, see Nassa Shells, 237 see Contracted Corbula, 457 Bat-wing Sea-slug, 283, fig. 60e habits, 17 Baughman’s Ark, 345 Bay Mussel, see Blue Mussel, 354 Beaded Miter, 248, pl. 26b Beaded Periwinkle, 134, pl. 19g Beaded Turret, 273, fig. 57m Beak in bivalve shell, 81 Bean Clam, see Gould’s Donax, 438 Bearded Ark, see Red-brown Ark, 343 Bearded Hoof-shell, 167 Bear Paw Clam, 37 Beatic Dwarf Olive, 247, pl. 20q Beau’s Murex, 202, pl. 10d Beau’s Vitrinella, 138 Beautiful Little Caecum, 147, fig. 37d Beautiful Striped Semele, see Cancellate Semele, 435 Beautiful Top-shell, 112 Beautiful Trifora, 159, pl. 19z Benedict’s Scallop, 364 Bent Mussel, see Hooked Mussel, 353 Bent-nose Macoma, 432, fig. 88d Bequaert, J. C., 205 Bequaert’s Murex, 205 Berry Dwarf Turban, 126 Berry, S. Stillman, 51, 341, 493 Bifurcate Mussel, 354 Big-end Chiton, 323 Bird Shell, see Broad-ribbed Cardita, 378 Bittersweet Clams, species of, 348 Bittiums, species of, 155-156, pl. 19 Bivalves, see clams Black Abalone, 92, pl. 2f Black Atlantic Planaxis, 150 Blackberry Drupe, 211, pl. 25v Black Clam, see Ocean Quahog, 381 Index Black Date Mussel, 356, pl. 28m Black Hebknet Shell, see Emperor Helmet, 193 Black Katy Chiton, 316, fig. 66b Black Limpet, 104 Black-lined Trifora, 159, pl. roy Black Musculus, 355, pl. 28g Black Screw Shell, see Fine-ribbed Auger, 266 Black Tegula, 119 Black Worm Shell, 143, pl. 21¢e Blake Report, 499 Blake’s Turret, 273, fig. 57h Bleeding Tooth, 128, pl. 4a Blind Limpet, Northern, 107, pl. 17} Blood Ark, 345, pl. 27t Blood-fluke disease, 4 Blown Basket Shell, see Common East- ern Nassa, 237 Blue Glaucus, 309 Blue Mussel, 354, pl. 35m Blue Point Oysters, 375 Blunt Jackknife Clam, 444, pl. 29v Boat Shell, see Slipper-shells, 170 Bonnets (Phalium), species of, 192-193, 19 Borel Astarte, 375, pl. 28q Boreal Awning Clam, 333 Boreal Hairy-shell, 167, pl. 24d Boreal Marginella, 257, fig. 56f Boring Clams, 32 Boring Petricola, 419 Boring Turret-shell, 141, pl. 21) Breathing, by snails, 24 by clams, 38 Briar Octopus, 487, fig. 100c Bridle Rimula, 95, fig. 30d Brief Squid, 482, fig. 99g Bright Ark, see White Bearded Ark, 342 British Columbia Crenella, 351, fig. 26g Broad-eared Scallop, see Kelp-weed Scallop, 365 Broad-ribbed Cardita, 378, pl. 30a Broad-ribbed Venus, see Imperial venus, 409 Broad Yoldia, 340, pl. 27e Bronn’s Dwarf Lima, 371 Brota Macoma, 433, fig. 88a Brown-banded Genota, 271, fig. 57g Brown-banded Wentletrap, 165, pl. 22e Brown-corded Neptune, 229, pl. 23s Brown Gem Clam, 419, fig. 85 Brown Horn Shell, see Florida Cerith, 153 Brown-lined Latirus, 241, pl. 11a Brown-lined Paper-bubble, 276, pl. 13q Brown Moon-shell, 186, pl. 5} Brown Paper Nautilus, 485, fig. g9e, f Brown Sargassum Snail, 156, pl. 21k Brown’s Barrel-bubble, 282 Brown Tegula, 119 Bubbles, species of, 277 Buccinums, species of, 225-227 Bull’s-eye, see Moon-shell, 186 Burch, John Q., 492 Burnt Rock Shell, see Lace Murex, 203 Burry, Leo, 200, 487 Burry’s Octopus, 487, fig. 10ob Bush’s Barrel-bubble, 280, pl. 26w Buttercup Lucina, 389, pl. 38f Cabinet, shell, 64, fig. 21 Cabrit’s Murex, 201, pl. 10h Cadulus, species of, 327 Caecums, species of, 146, fig. 37 Calico Clam, 416, pls. 1b; 39e Calico Scallop, 368, pl. 33} California Academy of Sciences, 69 California Bubble, 278 California Caecum, 147, fig. 37g California Donax, 438, pl. 31p California Horn Shell, 152 California Horse Mussel, 352, pl. 29-0 California Latiaxis, 220 California Lucina, 390, pl. 31¢ California Lyonsia, 468 California Pedicularia, 182, pl. 7b, ¢ California Sea-mussel, see Californian’ Mussel, 354 Californian Banded Pheasant, 127 Californian Cap-shell, 168 Californian Cone, 265 Californian Cumingia, 436, pl. 31v Californian Date Mussel, 356, pl. 29h Californian Frog-shell, 199, pl. zor Californian Glass Mya, 456 Californian Irus Venus, 412, pl. 3147 Californian Jackknife Clam, 443 Californian Liotia, 122, pl. 18u Californian Mactra, 445, fig. god Californian Marginella, 256 Californian Mussel, 354, pl. 29p Californian Nassa, 239 Californian Nuttall Chiton, 314 Californian Sunset Clam, 441, pl. 29n Californian Tagelus, 440, pl. 29u Californian Trivia, 179, pl. 20v Cameo Helmet Shell, see Emperor Helmet, 193 Campeche Angel Wing, 462, pl. 32t Cancellate Cantharus, 234 Cancellate Cyclostreme, 121 Cancellate Fleshy Limpet, 98, pl. 17k Cancellate Hairy-shell, 167, pl. 24b Cancellate Nut Clam, 335, fig. 70 Cancellate Semele, 435, pl. 30] Cancellated Lucapina, see Cancellate Fleshy Limpet, 98 Candé’s Phos, 231, pl. 25u Candy Stick Tellin, 426, pl. 4om; fig. 86e Canoe-bubbles, species of, 281 Cantharus, species of, 233 Capax Horse Mussel, 352 Cap-shells, species of, 168 Cardinal tooth in bivalve shell, 84 Caribbean Paper-bubble, 278, fig. 59¢ Caribbean Shipworm, 466, fig. 95¢ Caribbean Vase, 245, pl. 23-l Carinaria, Lamarck’s, 185, fig. 42 Subject Matter and Common Names Carinate Dove-shell, 222 Carinate Lacuna, 131, fig. 36a Carmine Marginella, 254, fig. 56a Carolina Cadulus, 327, fig. 69a Carolina Caecum, 149, fig. 37¢ Carolina Marsh Clam, 381, pl. 30bb Carolina Moon-shell, 187, pl. 22-1 Carol’s Fig Shell, 200 Carpenter’s Amphissa, 224, fig. 50c Carpenter’s Baby-bubble, 275 Carpenter’s Caecum, 148, fig. 371 Carpenter’s Doris, 304, pl. 16k Carpenter’s Dwarf Triton, 216, fig. 49a Carpenter's Dwarf Turban, 126, pl. 181 Carpenter’s Miniature Cerith, 157 Carpenter’s Nut Clam, 337 Carpenter’s Onchidella, 274 Carpenter’s Tellin, 426 Carrier-shells, species of, 172-173 Carrot Cone, 260, pl. 14a ) Carved Star-shell, 124, pl. 3h Catalina Forreria, 201, fig. 44c, d Catilliform Surf Clam, 448, fig. god Cat’s Eye Moon Shell, see Shark Eye, 186 Cat’s Eyes (operculum), 78 _ Cat’s Paw, see Kitten’s Paw, 361 _ Cavolines, species of, 296, fig. 64 _ Cayenne Keyhole Limpet, 96, pl. 17m | Ceriths, species of, 153-155, fig. 39; pl. | 19 _ Cerros Forreria, 200, fig. 44a, b _ Chace’s Wentletrap, 162 _ Chaffy Limpet, 105 _ Chalky Buttercup, 389, pl. 38e _ Chalky Macoma, 430, fig. 88f _ Chambered Nautilus, 48 _ Chank, West Indian, 244 _ Channeled Barrel-bubble, 280, pl. 26x _ Channeled Dogwinkle, 216, figs. 48b, c _ Channeled Duck Clam, 449, pl. 32q Channeled Neptune, 230, fig. 51d _ Channeled Solarelle, 110, fig. 32b, c Channeled Top-shell, 115, pl. 3q _ Channeled Turban, 123, pl. 3b _ Channeled Whelk, 236, pl. 23n _ Checked Borer, see Chubby Mya, 456 - Checked Pheasant, 126 _ Checkerboard, see Calico Clam, 416 Checkered Periwinkle, 134, pl. 20c Checkered Thorn Drupe, 212 _ Chestnut Astarte, see Smooth Astarte, 376 _ Chestnut Buccinum, 226, fig. 51¢ _ Chestnut Cowrie, 181, pl. 6b _ Chestnut Frog-shell, 198, pl. 25p — Chestnut Latirus, 240, pl. 11d _ Chestnut Turban, 123, pl. 3g Chest Rock Oyster, see Florida Spiny Jewel Box, 394 China Cockle, see Prickly Cockle, 398 Chinese Alphabet Cone, see Alphabet Cone, 260 Chinese Hat, Pacific, 169, pl. 20-1 Chink-shells, see Lacunas, 130 Chitons, collecting, 51 shell parts, 52, fig. 18 species of, 312-325 Chocolate-lined Top-shell, 112, pl. 3n Chubby Mya, 456 Cigar Pteropod, 299, fig. 64m Cingulas, species of, 135 Circled Dwarf Triton, 218, fig. 49b Circular Cup-and-saucer, 169, pl. 21-0 Clam, Soft-shell, 455, pl. 32x Clams, habitats, 31 feeding of, 35 growth, 33 habits, 43 reproduction, 41 Clark, Austin H., 264 Clark’s Cone, 264, pl. 14i Classification of clams, 332 Clathrate Trophon, 206 Cleaning shells, 62 Clear Jewel Box, 393, pl. 37a Cleft Clams, species of, 384 Clench, Mrs. W. J., 261 Clench, W. J., 68, 493, 499 Clench’s Helmet, 194 Clios, species of, 294, fig. 64 Clipped Semele, see Bark Semele, 435 Cloudy Cone, see Crown Cone, 262 Coat-of-Mails, species of, 312-325 Cock Stromb, see Rooster-tail Conch, 175 Cockle Clam, see Gaudy Asaphis, 439 Cockles, species of, 397-404 Coffee Bean Trivia, 177, pl. 21bb Collecting methods, 51, 56 Collection, making a, 63, fig. 21 Collections, outstanding, 68 Collections, private, 9 Color, production of, 20 Colorful Atlantic Natica, 191, pl. 5-l Columbelle Erato, 176 Columbian Amphissa, 224, fig. sob Columella, definition of, 76 Colus, species of, 22 Comb Bittersweet, 348, pl. 271 Common Atlantic Abra, 437, pl. 30v Common Atlantic Auger, 265, pl. 261 Common Atlantic Awning Clam, 333, pl. 27a Common Atlantic Diplodon, 383 Common Atlantic Marginella, 257, pl. 1m Common Atlantic Octopus, 486, fig. 100a Common Atlantic Slipper-shell, 170, pl. 21m Common Baby’s Ear, 1go, pl. 22s Common Californian Venus, 407, pl. 31] Common Crown Conch, 234, fig. 52 Common Dove-shell, 220, pl. 25bb Common Eastern Chiton, 319, fig. 68 Common Eastern Nassa, 237, pl. 23q Common Egg Cockle, 399, pl. 39k Common Fig Shell, 200, pl. gi Common Jingle Shell, 372, pl. 35k OF Common Northern Buccinum, 225 Common Northern Lacuna, 130, pl. 22p Common Northern Moon-shell, 189, fig. 22a Common Northwest Neptune, 230, pl. 24 Conan Nutmeg, 252, pl. 13k Common Pacific Egg Cockle, 400 Common Pacific Littleneck, 410, pl. 31m, n Common Pacific Octopus, 488 Common Pacific Squid, 482 Common Periwinkle, 132, pl. r9b Common Prickly-winkle, 134, pl. 19i Common Purple Sea-snail, 160, pl. 4j Common Rangia, 450, fig. 91 Common Rice Olive, 247 Common Shipworm, 467 Common Short-finned Squid, 483, fig. g9b Common Star Turret, 268, fig. 57e Common Sun-dial, 142, pl. 4m Common Washington Clam, 417, pl. 31-1 Common Western Corbula, 459 Common Western Spoon Clam, 473, fig. 97a Common West Indian Bubble, 277, pl. 26 Common West Indian Chiton, pl. 1d Common West Indian Simnia, 182, pl. 7a Compostella, 11 Concave Auger, 266, pl. 26] Concealed Arctic Chiton, 316, fig. 66c Concentric Nut Clam, 338 Concentric sculpture, definition of, 84 Conchologists, directory of, 492 Conchs (Strombus), species of, 174, pl. 324, 23 Cone shell sting, 5, fig. 1 Cones, species of, 260-265, pl. 14 Conrad’s False Mussel, 382 Conrad’s Thracia, 471, pl. 28y Conrad’s Transennella, 413, fig. 83¢ Conserved names in mollusks, 87 Conspicuous Chiton, 321 Constricted Macoma, 431 Contracted Corbula, 457 Convex Slipper-shell, 171, pl. 21n Coon Oyster, 31, 373, pl. 28d Cooper’s Atlantic Caecum, 148, fig. 37b Cooper’s Chiton, 323 Cooper’s Clam, Shiny, 421 Cooper’s Nutmeg, 253, pl. 24y Cooper’s Turret-shell, 141, pl. 20g Coquina Clam, habits of, 32 Coquina Shell, 437, pl. 30r Coral-boring Clam, 382, pl. 28p Coral-shell, Short, 220 Corbulas, species of, 456 Corrugated Razor Clam, 444 Costate Cuspidaria, 476 Costate Horn Shell, 152, pl. 19u Costate Lucina, 390 508 Costate Wentletrap, 162 Cowrie-helmet, 194, pl. 9c Cowrie, Panther, 7 Cowrie, Tiger, 7 Cowries, species of, 180, pl. 6 Crawford’s Nutmeg, 252, fig. 55b Crenellas, species of, 350 Crenulate Tellin, 429, fig. 86h Crenulated Paper-bubble, 283 Crested Oyster, 373, pl. 28c Crispate Slit-shell, 91 Cristate Limopsis, 347 Cross-barred Venus, 407, pl. 39h Cross-hatched Lucina, 391, pl. 30m Crosse’s Tun, 199, pl. 23g Crown Conch, Common, 234, fig. 52 Crown Cone, 262, pl. 14m Crusaders, 11 Cuming, Hugh, 5 Cumingias, species of, 436 Cup-and-saucers, species of, 169 Cup and Saucer Limpet, see Striate Cup-and-saucer, 170 Cuspidarias, species of, 475-477 Cut-ribbed Ark, 344, pl. 27-0 Cuttlefish bone, 480 Cuttlefish, species of, 479 Cyclostreme, 121 Cylinder Sun-dial, 142 Cyphomas, species of, 183, pl. 4 Dall’s Black Turret, 268, fig. 57] Dall’s Caecum, 147, fig. 37h Dall’s Deepsea Hoof-shell, 166 Dall’s Dwarf Gaza, 111, fig. 32d, e Dall’s Dwarf Tellin, 424, fig. 86d Dall’s Egg Cockle, 400 Dall’s Little Abra, 437, pl. 30w Dall’s Pitted Murex, 205, pl. 25) Dall’s Razor Clam, 443 Dall’s Rosy Top-shell, 112 Dall’s Treasured Simnia, 182, pl. 7f Dall’s Trophon, 208, fig. 46a Dall’s Wentletrap, 161, pl. 22c Dall, William H., 7 Dark Dwarf Turban, 126 Date Mussels, species of, 356 Decussate Bittersweet, 348, pl. 27h Decussate Crenella, 350 DeKay’s Dwarf Tellin, 423 Delicate Giant Turret, 268, pl. 13m Delphinula Nut Clam, 335, fig. 70 Deltoid Rock-shell, 214, pl. 25b, k de Marco, Simon, 68 Dentaliums, species of, 327, fig. 69 Diplodons, species of, 383 Dire Whelk, 232, fig. 50d Discord Musculus, 355, pl. 28c Disk Dosinia, 417, fig. 81¢ Dislocated Auger, see Common Atlantic Auger, 265 Dispersal of shells, 9, 10 Distorsios, species of, 196, pl. 25 Distribution, bathymetric, 18, 32 Divaricate Nut Clam, 336, fig. 72¢ Index Doc Bales’ Ark, 343, pl. 27k Docoglossate, 79 Dog-head Triton, 196, pl. 9] Dog-whelk, see Nassa or Dogwinkle Dogwinkles, species of, 214 Dohrn’s Volute, 251, pl. 13} Domingo Cardita, 378 Donax, species of, 437 Dosinias, species of, 417 Dotted Horn Shell, see Fly-specked Cerith, 154 Doris, species of, 299-307, pls. 15, 16 Dove-shells, species of, 220-224 Drake’s Moon-shell, 187, fig. 43a Dredging, 59, fig. 20 Drillias, species of, 270 Drills, species of, 211-213, 219 Drupes, species of, 211 Dubious Volute, 251 Duck Foot, see American Pelican’s Foot, 173 Dusky Tegula, 120, pl. 18y Dwarf Atlantic Planaxis, 150 Dwarf Balloon Eolis, 309, pl. 15¢ Dwarf Brown Periwinkle, 133, pl. 19k Dwarf Cerith, 154, pl. 19-0 Dwarf Deepsea Miter, 248 Dwarf Glass-haired Chiton, 318 Dwarf Hairy Triton, 195, pl. 25n Dwarf Keyhole Limpet, 97 Dwarf Olives, species of, 246 Dwarf Purple Sea-snail, 160, pl. 4-1 Dwarf Red Ovula, 181, pl. 22q Dwarf Suck-on Limpet, 106, pl. 17b Dwarf Surf Clam, 449, pl. 32-0 Dwarf Tiger Lucina, 391, pl. 30-1 Dwarf Tritons (Ocenebra), species of, 216 Dwarf Turbans, species of, 125 Dwarf Turton Clam, eggs of, 41 Dwarf White Moon-shell, 186 Dyes, 11 Dye Shell, see Wide-mouthed Purpura, 21 Dyson’s Keyhole Limpet, 97, pl. 17n Eared Ark, 344, pl. 27p Eastern Micro-cockle, 399 Eastern Mud Nassa, 240, pl. 23p Eastern Oyster, 375, pl. 28a Eastern Turret-shell, 141, pl. 21h Eastern White Slipper-shell, 172 Edentulous bivalve shell, 84 Edible Mussel, see Blue Mussel, 354 Egg-cases, of snails, 29, figs. 8, 9 literature on, 495 Egg Cockles, species of, 399 Egg laying, of Paper Nautilus, 49 of Periwinkle, 29 of Whelk, 30 Eggs, of clams, 41 Elegant Dosinia, 417 Elegant Fossarus, 176, pl. 25¢ Emarginate Dogwinkle, 216, fig. 48a Emerald Nerite, 130, pl. 4h Emperor Helmet, 193, pl. 23v Empress Venus, 404, pl. 38-1; fig. 81d Engina, White-spotted, 232, pl. 25w Eolis, species of, 307-310, pls. 15, 16 Equilateral, definition of, 82 Equivalve, definition of, 82, fig. 26h Eratos, species of, 176, pl. 22 Erect Worm-shell, 143-144 Eroded Periwinkle, 134, pl. 20a Eroded Turret-shell, 140, pl. 21-1 Ervilia, Concentric, 452 Escutcheon, fig. 27 Excavated Slipper-shell, 172 Exchanging shells, 66 Eye, of chitons, 53 of scallops, 43 Faba Crenella, 350, fig. 75a Falcate Date Mussel, 356, pl. 29k Fallen Angel Wing, 461 False Angel Wing, 420, pl. 32z; fig. ogt False Cerith, 153, fig. 39, pl. 19s False Cup-and-saucer, 165, pl. 21p False Dials, species of, 139 False Drill, 211, fig. 47f False Jingle Shell, 372, pl. 29d False Limpet, species of, 310, fig. 65 — False Mussel, Conrad’s, 382 False Prickly-winkle, 135, pl. 19h Fan Shell, see Zigzag Scallop, 362 Fargo’s Worm-shell, 145, pl. 21b Fat Colus, pl. 23u, not in text Fat Dove-shell, 221 Fat Gulf Donax, 438 Fathom = 6 feet Fat Horsemussel, see Capax Horse Mus sel, 352 Fat Neptune, 230, pl. 24s Fat Pacific Lepton, 397, fig. 80b Faust Tellin, 428, pl. 40] Fecal pellets, 36, fig. 13 Feeding, by snails, 21 by clams, 35 Fenestrate Limpet, 102, pl. 18t Festive Murex, 206, pl. 24-1 Fighting Conch, Florida, 174, pl. 5h Fig Shell, Common, 200, pl. 91 File Dogwinkle, 216, fig. 48d File Fleshy Limpet, 98, pl. 171 File Limpet, 102, pl. 18-0 File Paper-bubble, 283, fig. sof File Shell, see Lima, 370 File Yoldia, 340, fig. 71b Filose Turret, 273, fig. 57-1 Fimbriated Shipworm, 467, fig. 95f Fine-lined Lucina, 387, fig. 78h Fine-ribbed Auger, 266, pl. 26k Fine-sculptured Frog-shell, 198 Fingered Limpet, 103, pl. 18f Fingerprint Cyphoma, 184, pl. 4t Flame Auger, 265, pl. 13h Flame Helmet, 193 Flamingo Tongue, 183, pls. 8, 4r Flap-tipped Piddock, 463 Subject Matter and Common Names Flat Moon Shell, see Common Baby’s Ear, 190 Flat Slipper Shell, see Eastern White Slipper-shell, 172 Flattened Cardita, 380, pl. 28-l Flattish Surf Clam, 448, fig. goe Flat Tree Oyster, 358, pl. 35b Flat Worm-shell, 144, pl. 20d Flesh Sea Pen, see Amber Pen Shell, 360 Fleshy Limpets, species of, 98, pl. 17, 18 Florida Auger, 265 Florida Bubble, see Common West In- dian Bubble, 277 Florida Button, see Atlantic Modulus, 151 Florida Caecum, 146, fig. 37a Florida Cask Shell, see Giant Tun, 199 Florida Cerith, 153, pl. 19n Florida Cone, 261, pl. 14d Florida Horse Conch, 242, pl. 13a Florida Lucina, 387, pl. 381 Florida Marsh Clam, 381, pl. 30y Florida Purple, see Florida Rock-shell, 213 Florida Rock-shell, 213, pl. 25a Florida Semele, see White Atlantic Semele, 434 Florida Slender Chiton, 320 Florida Slit-shell, 91, fig. 29 Florida Spiny Jewel Box, 394, pl. 37g Florida Tivela, 412 Florida Top-shell, see Jubjube Top- shell, 113 Florida Tusk, 330 Florida Worm-shell, 145, pl. 21a Flying Squid, 47, 484 Fly-specked Cerith, 154, pl. 19m Foliated Thorn Purpura, 218, pl. 24h Food, influence on growth, 21 of snails, 21-23 of clams, 35 Forreria, species of, 200 Fossa Nut Clam, 337 Fossarus, Elegant, 176, pl. 25¢ Fossor Donax, 437 Four-ribbed Lucina, 387, fig. 78d, e Four-spotted Trivia, 178 Four-threaded Bittium, 156 : Four-toothed Cadulus, 328, fig. 6gb Four-toothed Nerite, 128, pl. 4b Fragile Atlantic Mactra, 445, pl. 32s Frail Clam, see Fragile Atlantic Mactra, 445 Frilled Californian Venus, 408, pl. 311 Frilled Dogwinkle, 215, figs. 48e-h Frilled Panama Venus, not in text, pl. 31d Frilled Paper Cockle, 398, pl. 32¢ Frog-shells, species of, 197-199 Frond Eolis, 307, pl. 15e Fucan Cockle, 403 Fuzzy Chiton, 326 Gabb’s Mangelia, 272 Gape in bivalve shell, 82 Gaper, Pacific, 450, pl. 312z Gardner’s Yoldia, 340 Garrett, Andrew, 5 Gastropods, Life of, 16 Gaudy Asaphis, 439, pl. 40a Gaudy Cantharus, 233 Gaudy Frog-shell, 198, pl. 9k Gazas, species of, 111, 118 Gem Arene, 122, pl. 17q Gem Murex, 206, pl. 24e Gem Top-shell, 115, fig. 33d Geoduck, 454 Geographic limits of this book, 89 Giant American Bittersweet, 349 Giant Atlantic Cockle, gor, pl. 32a Giant Atlantic Pyram, 2809, pl. 4q Giant Band Shell, see Florida Horse Conch, 242 Giant Clam, habits of, 37 Giant Conch, see Queen Conch, 174 Giant Date Mussel, 357, pl. 28k Giant Eastern Murex, 203, pl. rob Giant False Donax, 439, pl. 32u Giant Forreria, 200, pl. 241 Giant Ow! Limpet, to1, pl. 18} Giant Pacific Chiton, 318, fig. 66d Giant Pacific Coast Bittium, 155 Giant Pacific Cockle, 398, pl. 31a Giant Pacific Oyster, see Japanese Oys- ter, 375 Giant Pacific Scallop, 361, pl. 29b Giant Panama Spindle, pl. 24zz Giant Panope, see Geoduck, 454 Giant Rock Scallop, 369, pl. 29a Giant Squid, 47 Giant Squid, Harvey’s, 483, fig. 99c Giant Tun, 199, pl. 23f Giant Western Nassa, 240, pl. 20s Gibb’s Clam, 377, pl. 30z Gilded Tegula, 120, pl. 18k Gills, of clams, 37, 39, fig. 15 Glacial Buccinum, 226, pl. 24t Glacial Cuspidaria, 475, fig. 97b Glandular Crenella, 350, pl. 28} Glass-haired Chiton, 318 Glassy Lyonsia, 468, pl. 28u Glaucus, Blue, 309 Globe Purple Sea-snail, 160, pl. 4k Glorious Top-shell, 116, fig. 33a Glory-of-the-Atlantic Cone, 264, pl. 14-1 Glory-of-the-Seas Cone, 5 Glory-of-the-Seas Venus, 415, pl. 391 Glossary of terms, 74-84, figs. 23-28 Glossy Dove-shell, 222, pl. 25dd Golden-banded Cone, 260, pl. 14g Golden Cowrie, 6 Golden-lined Marginella, 254, fig. 56b Golden-mouthed Lucina, see Buttercup Lucina, 389 Gold-mouthed Triton, 196, pl. 25q Goliath Conch, 6 Golisch’s Lepton, 396 Gooeyduck, see Geoduck, 454 Gould’s Baby Chiton, 313 Gould’s Barrel-bubble, 282, pl. 26r 509 Gould’s Donax, 438, pl. 31q Gould’s Dove-shell, 222, pl. 20m Gould’s Pacific Mactra, 446 Gould’s Pandora, 470, fig. 96c Gould’s Paper-bubble, 279 Gould’s Shipworm, 466, fig. 95d Graceful Dwarf Triton, 217, pl. 24m Grant and Gale Macoma, 433, fig. 88h Grant’s Chama, 393 Granular Frog-shell, 198, pl. 25-0 Granulated Cuspidaria, 476 Granulated Sundial, see Common Sun- dial, 142 Granulose Top-shell, 115, pl. 18s Gray Atlantic Auger, 266, pl. 26g Gray Hairy-shell, 168, pl. 24c Gray Pygmy Venus, 408, pl. 321 Great Alaskan Tellin, 425, fig. 87c, d Great Heart Cockle, see Giant Atlantic Cockle, 402 Great Keyhole Abalone, 99, pl. 18a Great Piddock, 462, fig. 94¢ Great Tellin, 427, pl. 4oi Great White Lucine, see Tiger Lucina, 391 Greedy Dove-shell, 221, pl. 25ee Green Abalone, 93, pl. 2b Green-base Tegula, 119 Green Jackknife Clam, 444, pl. 30n Greenland Cockle, 4o1, pl. 32d Greenland Margarite, 108, fig. 31d Greenland Moon-shell, 189, pl. 22k Green Music Volute, 250 Green Neritina, see Emerald Nerite, 130 Green Razor Clam, see Green Jackknife Clam, 444 Green’s Miniature Cerith, 157, pl. 19v Green Star-shell, 124, pl. 3) Growth, of clams, 33 of snails, 19, fig. 5 Growth lines, definition of, 77 Gulf Oyster Drill, 212 Gulf Periwinkle, see Marsh Periwinkle, 132 Haas, Fritz, 68 Habitats, of snails, 17 Hairy Colus, 229, pl. 23t Hairy Mopalia, 315 Hairy-shells, species of, 167 Half-scratched Tusk, 331 Half-slipper Shell, 170 Hamate Nut Clam, 339, fig. 26d Handsome Trophon, 207, fig. 46d Hanna, G. Dallas, 69 Hard-edged Fleshy Limpet, 99, pl. 18d Hard-shelled Clam, see Quahog, 406 Harford’s Spindle, 243, fig. 54a Hartweg’s Baby Chiton, 314 Harvester Murex, see Rose Murex, 202 Hatchet Surf Clam, 448, fig. 90a Hawk-wing Conch, 175, pl. 5¢ Hay’s Rock-shell, 213 Hearty Rupellaria, 421 Heath’s Doris, 300, pl. 161 510 Hectocotylus arm, 50 Helix Vitrinella, 138 Helmet-bubble, Orbigny’s, 276, pl. 26v Helmet Puncturella, 96, fig. 30c Helmets, species of, 193 uses of, 193 Hemphill?’s Dish Clam, see Hemphill’s Surf Clam, 448 Hemphill’s Lima, 371, pl. 29c¢ Hemphill’s Surf Clam, 448, fig. gob Henderson’s Miter, 249, pl. 26c Heptagonal Caecum, 148, fig. 37k Hertlein, Leo, 69 Heteropods, species of, 184, 185 Hidalgo’s Murex, 203, fig. 45a Hinds’ Mopalia, 316 Hinds’ Nut Clam, 339 Hinds’ Scallop, 365, pl. 34-1 Hinge of clam shells, 81, fig. 28 Hooded Puncturella, 96, fig. 30a, b Hoof-shells, species of, 166, pl. 21 Hooked Mussel, 353, pl. 35n Hooked Surf Clam, 447 Hopkins’ Doris, 307, pl. 16a Horn Shells, species of, 151-152, pl. 19 Horse Conch, Florida, 242, pl. 13a Hotessier’s Wentletrap, 162, pl. 22 Humphrey’s Wentletrap, 164, pl. 22d Hundred-lined Cockle, 399 Iceland Cockle, 403, pl. 32e Iceland Moon-shell, 187, pl. 22r Iceland Scallop, 365, pl. 27-1 Identification features, 72, 81 Identification services, 67 Ida’s Miter, 249, pl. 20p Ida’s Tellin, figs. 87a, 28h Immaculate Moon-shell, 186 Imperial Venus, 409, pl. 39¢ Incongruous Ark, 346, pl. 27y Incurved Cap-shell, 168 Indian Money Tusk, 330, fig. 6of Inequilateral, definition of, 82 Inequivalve, definition of, 82 Inflexed Simnia, 183, pl. 7h Ink from mollusks, 14 Intricate Baily-shell, 231, pl. 25t Iris Tellin, 427 Irregular Worm-shell, 143, pl. 21d Irus Macoma, 433, fig. 88e Ivory Cerith, 154, pl. 19q Ivory Tusk, 331, fig. 69e Jackknife Clams, species of, 443 Jacob’s Scallop, 11 Jamaica Limpet, 106, pl. 17¢ Janthina snails, 17 Japanese Abalone, 94, pl. 2e Japanese Littleneck, 410 Japanese Oyster, 375, pl. 29¢ Jasper Cone, 262, pls. 14n, 22x Jasper Dwarf Olive, 246, pl. 111 Jewel Boxes (Chama), species of, 391- 394 Jewett’s Marginella, 258 Index Jingle Shells, species of, 372 Johnsonia (Journal), 493, 499 Joseph’s Coat Amphissa, 223, fig. 50a Joubin’s Octopus, 488, fig. rood Jubjube Top-shell, 113, pl. 3p Julia’s Cone, 261, pl. 14b Junonia, 250, pl. 13f Juno’s Volute, see Junonia, 250 Kamchatka Abalone, see Japanese Aba- lone, 94 Keeled Sun-dial, 143, fig. 22g; pl. 4n Keen, Myra, 69 Keep’s Baby Chiton, 314 Kellet’s Whelk, 231, pl. 24w Kelp-weed Scallop, 365, pl. 341 Kelsey’s Cingula, 135 Kelsey’s Date Mussel, 357, pl. 291 Kelsey’s Milner Clam, 380, fig. 76 Kennerley’s Venus, 410 Kennicott’s Buccinum, 227, fig. 51g Keraudren’s Atlanta, 184 Key Caecum, 147 Keyhole Limpet, growth of, fig. 5 Keyhole Limpets, species of, 94-98, pls. 17, 18 King Helmet, 193 King’s Crown Conch, see Common Crown Conch, 234 King Venus, 409, pl. 39a Kitten’s Paw, 361, pl. 35¢e Knave Marginella, 259, fig. 56-1 Knobbed Triton, 196, pl. 25r Knobbed Whelk, 235, pl. 231 Knobby Keyhole Limpet, 100, pl. 17d Knobby Top, see Chestnut Turban, 123 Kobelt’s Spindle, 243, fig. 54b Krebs’ Sun-dial, 143, pls. 4-0, 21y Krebs’ Wentletrap, 163, fig. 4oc La Belle Marginella, 256, fig. 56d Lace Murex, 203, pl. roe Lacunas, species of, 130 Ladder Horn Shell, 152, pl. 19x Ladder Shell, see Ladder Horn Shell, 152 Lady-in-Waiting Venus, 407, pl. 39g Lamarck’s Carinaria, 185, fig. 42 Lamellaria, San Diego, 175, fig. 43d Lamellose Solarelle, 110, pl. 17x Lamellose Wentletrap, 165, pl. 22a Lamp Shell, see West Indian Chank, 244 La Perouse’s Lepton, 394 Large Cockle, see Giant Cockle, 4o1 Large Strigilla, 428, pl. 4oc Lateral Musculus, 355, fig. 75c Lateral tooth in bivalve shell, 84 Latiaxis, California, 220 Latirus, species of, 240 Laurent’s Scallop, 362, pl. 33f Leafy Jewel Box, 392, pl. 37b Leafy Rock Oyster, see Leafy Jewel Box, 392 Lean Spoon Clam, 474, pl. 28v Atlantic Lebour, Marie, 30 Left-handed Whelk, see Whelk, 236 Lentil Astarte, 376, pl. 28-0 Lepton Clams, species of, 394 Lettered Olive, 245, pl. 12a Lewis and Clark Expedition, 7 Lewis’ Moon-shell, 189, pl. 24n Life cycle, of snail, 30 Ligament, definition of, 83 Lightning Venus, 414, pl. 39d Lightning Whelk, 236, pl. 23-0 Ligula index, explanation of, 486 Limas, species of, 370 Limopsis, species of, 347, fig. 73 Limpets, Keyhole, 96-101 Limpets, species of, 101-107, pls. 17, 18 Lindsley’s Crassinella, 377, pl. 30b Lined Bittersweet, see Atlantic Bitter- sweet, 348 Lined Periwinkle, see Marsh Periwinkle. 132 Lined Red Chiton, 313 Lined Tellin, see Rose Petal Tellin, 4277 Linne’s Puncturella, 95 | Lintea Tellin, 430, fig. 86g Lion’s Paw, 366, pl. 33b Liotias, species of, 121 Lip Triton, 196, pl. 25m Lirulate Margarite, 108, fig. 31e Lister’s Keyhole Limpet, 96, pl. 17-1 Lister’s Tree Oyster, 358, pl. 35a | Lister’s Venus, see Princess Venus, 404) Little Box Lepton, 395 Little Corrugated Jewel Box, 392, pl 37d Little Horn Caecum, 150, fig. 37e | Little Horn Shell, see Middle-spineé © Cerith, 154 Little Knobby Scallop, 364, pl. 34f | Little Moon Shell, see Colorful Atlantic 9 Natica, 191 Little Oat Marginella, 259, fig. 56k | Little Screw Shell, see Common Atlan- 9) tic Auger, 265 | Little White Lucine, see Dwarf Tiger } Lucina, 392 | Little White Trivia, 178, pl. z1cc Littorine, see Periwinkles, 132 Livid Macron, 234, pl. 24x Livid Natica, 191, pl. 22-0 Lobed Moon Shell, see Shark Eye, 186 Locomotion, in clams, 43, 45, fig. 17 in octopus, 49 Loebbeck’s Simnia, 183, pl. 71 Long Clan, see Soft-shell Clam, 455 Longhorned Smoke Shell, pl. 23w Long-spined Star-shell, 123, pl. 3k, m Lord’s Dwarf Venus, 411, fig. 82 Lovely Miniature Lucina, 385, fig. 78¢ Lovely Pacific Solarelle, 111, fig. 31b Lucinas, species of, 385-391 Luminescence in squid, 49 Lunar Dove-shell, 223, pl. 25g¢ Lunar-marked Columbella, see Lunar Dove-shell, 223 Lunate Crassinella, 377, fig. 28k Lunule, definition of, 82, fig. 27 Lurid Dwarf Triton, 217, figs. 49c, d Lynnhaven Oysters, 375 Lyonsias, species of, 468 MacFarland’s Blue Doris, 303 MacFarland’s Grand Doris, 304, pl. 16b MacFarland’s Pretty Doris, 300, pl. 16g Macomas, species of, 430-434 Macron, Livid, 234, pl. 24x Mactra Clams, species of, 445 Maculated Baby’s Ear, 190 Maculated Doris, 304, pl. 16f Magdalena Chiton, 321 Magnum Cockle, 397 Magpie Shell, see West Indian Top- shell, 117 Mahogany Clam, see Ocean Quahog, 381 Mahogany Date Mussel, 357, pl. 28n Maltbie’s Trivia, 178, pl. 21z Mangelias, species of, 272 Mantle-arm index, 486 Many-Angled Drill, see False Drill, 211 Many-lined Lucina, 386, fig. 78f Many-named Caecum, 147, fig. 37m Many-ribbed Ark, 344 Many-ribbed Scallop, see Atlantic Bay Scallop, 367 Many-ribbed Trophon, 207, fig. 46c Marbled Chiton, 325 Margarites, species of, 107-110, fig. 31, Ib3 Marvinsl tooth (radula), 79 Margin of bivalve shell, 82 Marginellas, species of, 254-260, pl. 11; fig. 56 Maria’s Turret-shell, 142, pl. 2oh Marsh Periwinkle, 132, pl. 19¢ Martesias, species of, 464 Mask Limpet, 103, pl. 18q Mauger’s Erato, 176, pl. 22w Mauve-mouth Drill, 211, fig. 47¢ Mayor’s Cadulus, 328 Mayr, Ernst, 72 Maze’s Cone, 264, pl. 14k McGinty’s Cyphoma, 184, pls. 8, 4s McGinty’s Distorsio, 197, pl. 25z McGinty’s Latirus, 241, pl. 11b Measled Cowrie, 180, pl. 6d Melo, Miniature, 276, pl. 26u Mera Tellin, 423, fig. 86c ~ Meropsis Tellin, 426, pl. 30u Merten’s Chiton, 322 Mesh-pitted Chiton, 320 Messanean Nut Clam, 337 Middle-spined Cerith, 154, pl. r9p Mildred’s Scallop, 363, pl. 34c Milk Conch, 174, pl. 23b Milk Moon-shell, 185, pl. 221 Milky Pacific Venus, 411, pl. 31f Subject Matter and Common Names Milky Turret-shell, 141 Miniature Ceriths, species of, 157 Miniature Melo, 276, pl. 26u Miniature Pheasant, 127 Miniature Triton Trumpet, 233, pl. 13-0 eee Wentletrap, 163, fig. gob; pl. 22 Miters, species of, 248, pls. 13, 26n Modest Tellin, 425, pl. 31u Modulus, Atlantic, 151, fig. 38 Money Cowrie, 7 Money Wentletrap, 165 Monterey Cingula, 135 Monterey Doris, 299, pl. 16h Monterey Miniature Cerith, 158 Monterey Tegula, 121, pl. 18x Moon Snail, feeding, 22, fig. 6 Moon-shells, species of, 185-190, piss 5; 22 Moore, Hilary B., 247 Moore’s Dwarf Olive, 246 Mopalias, species of, 315 Morch’s Pitted Murex, 205, pl. 251 Morrhua Venus, 414, pl. 32-1; fig. 81e Morris, Percy, 153, 164, 174, 203 Morrison, J. P. E., 68 Morro Mangelia, 272, fig. 571 Morton’s Egg Cockle, 400, pl. 39-1 Mossy Ark, 342, pl. 27] Mossy Mopalia, 315 Mottled Caecum, 149, fig. 37f Mottled Red Chiton, 313 Mottled Trifora, 159, pl. 19zz Mottled Venus, see Lady-in-waiting Venus, 407 Mouse Cone, 262, pl. 14-0 Mud-flat Octopus, 489 Muller’s Nut Clam, 336 Murex, species of, 201-204, pl. 10 Muscle scars in bivalves, 83 Musculus, species of, 355 Museum Comparative Zodlogy, 68 Music Volute, Common, 250, pl. 13g Mussel poisoning, 39 Mussels, species of, 351-354 Mya, Arctic Rough, 453 Myopsid squids, species of, 479 Name changing, 86 conservation, 87 Names of mollusks, 85 Narrow Dish Clam, see Catilliform Surf Clam, 448 Nassa Mud Snail, 18, fig. 3 Nassas, species of, 237-240 Naticas, species of, 191 Native Pacific Oyster, 374, pl. 20f Nautilus, Chambered, 48 Paper, 49, 485 Nautilus, The (Journal), 492 Near Nut Shell, see Atlantic Nut Clam, 334 Neat-ribbed Keyhole Limpet, 98 Needle-pteropods, species of, 294, fig. 64 Salat Neptunes, species of, 229-231 Nerites, species of, 128-130, pl. 4 Netted Olive, 245, pl. 12 New England Nassa, 239, pl. 23} Noble Canoe-bubble, 281 Noble False Dial, 139 Noble Pacific Doris, 300, pl. 16c Noble Wentletrap, 161, fig. 4oc Nomenclature, 85 Norris Shell, 117, pl. 18m North Atlantic Top-shell, 113 Northeast Lucina, 389, pl. 38; Northern Blind Limpet, 107, pl. 17} Northern Cardita, 379, pl. 28t Northern Dwarf Cockle, 404, pl. 30c pea Dwarf Tellin, 422, pl. 30x; fig. 86 Northern Green Abalone, 93 Northern Horse Mussel, 351, fig. 26} Northern Propeller Clam, 453 Northern Quahog, 406, pl. 32h Northern Razor Clam, see Pacific Razor Clam, 442 Northern Rosy Margarite, 107, pl. 17t Northern Rough Periwinkle, 133, pl. 19d Northern Yellow Periwinkle, 133, pl. 1of Northwest Onchidella, 275 Northwest Pacific Trophon, 208, fig. 46f Northwest Ugly Clam, 469, pl. 29m Nucleus Scallop, 368, pl. 34h Nudibranchs, species of, 299-310, pls. NS epelO Nut Clam, feeding by, 38, fig. 14 Nut Clams, species of, 334 Nutmegs, species of, 252 Nuttall’s Bladder Clam, 469, pl. 29q Nuttall’s Cockle, 403, pl. 31b Nuttall’s Lucina, 388, pl. 31¢ Nuttall’s Mahogany Clam, 439, pl. 29x Nuttall’s Thorn Purpura, 219, pl. 24f Obscure Solarelle, 110, fig. 31f, g Ocean Quahog, 381, pl. 32f Octopus, habits, 47 species of, 485-489 Odostomes, species of, figs. 62, 63 Oigopsid squid, species of, 483 Oldroyd’s Fragile Moon-shell, 188, fig. 43€ Olive Nerite, 129, pl. 4g Olives, species of, 245 Onchidella, Florida, 274 One-banded Lacuna, 131, fig. 36b Onyx Slipper-shell, 171, pl. 20f Open-mouthed Purple, see mouthed Purpura, 213 Operculum, definition of, 77, fig. 24 Opisthobranchs, species of, 274-310 Orange-banded Marginella, 258, pl. 11p Orange Hoof-shell, 166 Orange Marginella, 254, pl. 11k Orange-spiked Doris, 305, pl. 16e Wide- 512 Orange-tipped Eolis, 308, pl. 15) Orbigny’s Barrel-bubble, 282, pl. 26q Orbigny’s Sun-dial, 142, pl. 21x Orcutt’s Caecum, 149, fig. 37-1 Oregon Triton, 194, pl. 24g Ornamented Spindle, 243, pl. ric Ornate Scallop, 363, pl. 34b Orpheus Trophon, 208, fig. 46e Otto’s Spiny Margarite, 110 Oval Corbula, 456 Owl Limpet, see Giant Owl Limpet, 101 Oyster Drills, species of,213 Oysters, species of, 373-375, pls. 28, 29 Oyster Turret, 270, pl. 26n Pacific Awning Clam, 333 Pacific Bob-tailed Squid, 479 Pacific Chinese Hat, 169, pl. 20-1 Pacific Cleft Clam, 384, fig. 77a Pacific Crenulate Nut Clam, 335 Pacific Gaper, 450, pl. 312 Pacific Grooved Macoma, 434 Pacific Half-slipper Shell, 170, pl. 20k Pacific Left-handed Jewel Box, 393 Pacific Mud Piddock, 461 Pacific Orange Hoof-shell, 166 Pacific Orb Diplodon, 383 Pacific Pink Scallop, 364, pl. 34k Pacific Plate Limpet, 104 Pacific Razor Clam, 442, pl. 29y Pacific Rough Piddock, 462 Pacific Spear Scallop, 364, pl. 34] Pacific Thorny Oyster, 370, pl. 36a Pacific White Venus, 416 Painted Balloon Eolis, 310, pl. 15h Painted Cantharus, see Tinted Can- tharus, 233 Painted Limpet, 104 Painted Spindle, 244, fig. 54c Pale Northern Moon-shell, 190, fig. 43¢ Pale Tulip, see Banded Tulip, 242 Pallial sinus, definition of, 84 Panama Horse Conch, 242 Panamanian Vase, 245 Pandoras, species of, 469 Panelled Tusk, 328 Panther Cowrie, 7 Paper-bubbles, species of, 276, 283 Paper Fig Shell, see Common Fig Shell, 200 Paper Mussel, 353, pl. 281 Paper Nautilus, Common, 485, plo 1c egg laying, 49 Paper Scallop, 362 Paper Spoon Clam, 472, pl. 28w Papillose Eolis, 308, pl. 15g Parasitism, 19, fig. 4 of sea cucumber, 23 Parietal wall, definition of, 76 Partridge Tun Shell, see Atlantic Par- tridge Tun, 199 Pea-pod Borer, see Falcate Date Mussel, 356 Pea Strigilla, 429 Index Pearl Oyster, Atlantic, 359, pl. 35¢ Pearly Jingle, see Peruvian Jingle Shell, 372 Pearly Monia, see False Jingle Shell, 372 Pear-shaped Marginella, 260, fig. 56n Pear Whelk, 236, pl. og Pebble-shell, see Lord’s Dwarf Venus, 4ll Pectens, species of, 361 Pectinate Cuspidaria, 477 Pedicularia, Decussate, 181, pl. 7d Pelagic mollusks, Janthina, 17 pteropods, 17 Pelecypod features, 81 Pelican’s Foot, American, 173, pl. 23c Penciled Dove-shell, 221 Pender’s Nut Clam, 339 Pennsylvania Lucina, 385, pl. 38h Pen Shells, species of, 360 structure of, 34 Periostracum, definition of, 77 Peristome, definition of, 75 Periwinkles, species of, 132-134, pls. 19, 20 Perry’s Drillia, 270 Peruvian Jingle Shell, 372, pl. 29e Perverse Whelk, 236, pl. 23k Pheasants, species of, 126 Philippi’s Nutmeg, 253, fig. 55d Phoenicians, 11, 12 Piddocks, species of, 461 Pillowed Lathe-shell, see Western Bar- rel-bubble, 281 Pilose Doris, 305, pl. 15b Pilsbry, H. A., 68, 138 Pilsbry’s Tusk, 330, fig. 69d Pimpled Diplodon, 383 Pink Abalone, 93, pl. 2c Pink Conch, see Queen Conch, 174 Pisa Shell, see Miniature Triton Trum- pet, 233 Pismo Clam, 412, pl. 31h, fig. 28d Pitted Murex, 204, fig. 45b Planaxis, species of, 150 Platform Mussel, see Conrad’s False Mussel, 382 Plectrum Buccinum, 225, fig. 51a Plee’s Stripped Squid, 483 Pleurobranch, Atlantic, 286, fig. 61 Pleurotomarias, 92 Plicate Egg Shell, see Single-toothed Simnia, 182 Plicate Horn Shell, 152, pl. rot Pliny, 11 Pointed Cingula, 136 Pointed Egg Shell, see Common West Indian Simnia, 182 Pointed Marginella, see Common Atlan- tic Marginella, 257 Pointed Nut Clam, 338 Pointed Venus, 409, pl. 39} Poisoning by mussels, 39 Poisonous snails, 4 Polishing shells, 63 Polite Marginella, 258 Ponderous Ark, 346, pl. 27z; fig. 28a Popular books listed, 491 Popular names, 85 Poromya, Granular, 475, pl. 30s Porter’s Blue Doris, 303, pl. 16-1 Portuguese Oyster, 374 Posterior canal, definition of, 76 Poulson’s Dwarf Triton, 218, pl. 24k Pourtales’ Abalone, 94 Pourtales’ Glass Scallop, 369, pl. 27¢ Precious Wentletrap, 6 Prehistoric uses, 7 Pribiloff Neptune, 230, pl. 24r Prickly Cockle, 397, pl. 39-0 Prickly Jingle Shell, 372 Prickly-winkles, species of, 134 Princess Marginella, 257, fig. 56] Princess Venus, 404, pl. 32m Priority, rule of, 85, 86 Prodissoconch, definition of, 81 Promera Tellin, 424, fig. 86c Pronunciation of scientific names, 87 Propeller Clam, Northern, 453 Protobranchs, species of, 334 Pteropods, species of, 292-299, fig. 64 Punctate Mangelia, 272, fig. 57a Puncturellas, species of, 95, 96 Puppet Margarite, r1o9, fig. 31¢ Purple Clam, see Nuttall’s Mahogany Clam, 439 ; Purple Drill, see Mauve-mouth Drill. 211 Purple Dwarf Olive, 247, pl. 121 Purple Dye,-12; 13 Purple-hinged Scallop, see Giant Rock Scallop, 369 Purple Sea-snails, habits, 17 species of, 160, pl. 4 Purplish Pacific Tagelus, 441, pl. 29s Purplish Semele, 435, pl. gob Purplish Slender Chiton, 320 Purplish Tagelus, 440, pl. 30g Purpuras, species of, 213 Pygmy Colus, 229, pl. 23m Pyrams, species of, 288, figs. 62, 63 Quadrate Paper-bubble, 283, fig. 59e Quahog, Northern, 406, pl. 32h Queen Charlotte Macoma, 433 Queen Conch, 174, pl. 23a Queen Helmet Shell, see Emperor Hel- met, 193 Queen Marginella, 256, fig. 56¢e Queen Tegula, 120, pl. 3f Queen Venus, 405, pls. 38m, 32n Quoy’s Pleurotomaria, 92 Rachidian tooth, 78 Rachiglossate, 79 Radial sculpture, definition of, 84 Radula, 78, figs. 6, 25 Ragged Sea-hare, 286 Ram’s Horn, see Common Spirula, 478 Rangia, Brown, 450, fig. 91 Rattle Shell, see Blackberry Drupe, 211 Ravenel’s Dove-shell, 223, pl. 25cc Ravenel’s Egg Cockle, 400 Ravenel’s Scallop, 362, pl. 33g Rayed Cockle, see Gaudy Asaphis, 439 _ Razor Clams, species of, 442 Recluz’s Moon-shell, 187, pl. 20i _ Red Abalone, 92, pl. 2a ~ Red-brown Ark, 343, pl. 27q Reddish Mangelia, 272 Red-fingered Eolis, 310, pl. 15a Red Northern Chiton, 322 Red tide, 39 Red Turban, 125, fig. 35 Reed Tusk, 331 Reflexed Haloconch, 131 Regular Chiton, 321 Regular Marginella, 258 ee cider, Harald A., 68 Rehder’s Baby-bubble, 275 Reproduction, in snails, 24 in clams, 4o -Resilium, definition of, 83 Respiration, in snails, 24 in clams, 38 _Reticulate Ark, see White Miniature ; Ark, 343 -Reticulate Wentletrap, 163, fig. god ‘Reticulated Cowrie-helmet, 194, pl. 9c Reticulated Helmet, see Reticulated Cowrie-helmet, 194 Rhipidoglossate, 79 Ribbed Horsemussel, see . Ribbed Mussel, 351 1 Ribbed Pod, see Atlantic Razor Clam, 442 _ Ribbed Stromb, see Milk Conch, 174 _ Ribbed Top-shell, 116, fig. 33g Ribbed Western Corbula, 459 Rice Shell, see Common Rice Olive, 247 Rim Shell, see Common Atlantic Margi- nella, 257 Rimulas, species of, 94, 95 Ringed Top-shell, 115, fig. 33f Rio Janeiro Chiton, 319, fig. 67¢ Rissoinas, species of, 136-138 Ritter’s Trivia, 179 Rocellaria, Atlantic, 459 _Rock-boring Mussel, see Kelsey’s Date Mussel, 357 Rock-dwelling Semele, 435, pl. 29t Rock Oyster, see Jewel Box, 392 Rock-shells (Thais), species of, 213 Roden Mounds, 7 Rollins College, 68 Roosevelt, F. D., 4or1 Roosevelt’s Marginella, 254, pl. 11-0 Rooster-tail Conch, 175, pl. 5e Rose Cockle, see Prickly Cockle, 397 Rose Murex, 202 Rose Petal Semele, 435, pl. z29w Rose Petal Tellin, 427, pl. goh Rostrate Cuspidaria, 476, pl. 32) Rostrate Piddock, 464 Rosy Jackknife Clam, 444 Atlantic Hel Subject Matter and Common Names Rosy Keyhole Limpet, 100, pl. 17e Rough File Shell, see Antillean Lima, 370 Rough Girdled Chiton, 317, fig. 67a Rough Keyhole Limpet, 97, pl. 18b Rough Lima, 370, pl. 35f, o Rough Limpet, 103, pl. 18-1 Rough Nuttall Chiton, 314 Rough Scallop, 367, pl. 34d, e Rough Vase Shell, see Caribbean Vase, 245 Royal Bonnet, 192, pl. oh Royal Comb Venus, 415, pl. 39f Royal Florida Miter, 248, pl. 131 Royal Marginella, 256, pl. 11-1 Ruffled Rimula, 94, pl. 17-0 Rupellarias, species of, 420 Rustic Rock-shell, 214, pl. 25f Rusty Dove-shell, 220 Sailor's Ear, see Channeled Duck Clam, 449 Sallé’s Auger, 267 Salmon Tellin, 426, pl. 31ry Samuel, Marcus, 11 Sanded Lyonsia, 468 Sanderson’s Paper-bubble, 278, fig. 59d San Diego Lamellaria, 175, fig. 43d San Diego Limopsis, 347, fig. 73 San Diego Scallop, 361, pl. 33e San Diego Shipworm, 467 Sand Pandora, 470 Sandpaper Trophon, 208 San Pedro Auger, 267 San Pedro Dwarf Olive, 247 San Pedro Trifora, 159 Santa Barbara Spindle, 244, pl. 24z Santa Rosa Murex, 206, fig. 45d Sardonyx Helmet, see King Helmet, 193 Sargassum Nudibranch, 308 Sargassum Snail, Brown, 156, pl. 21k Saw-toothed Pen Shell, 360, pl. 27v Saxicave, Arctic, 452, fig. 92a Say, Thomas, 68 Say’s Chestnut Mussel, 356 Say’s False Limpet, 311, fig. 65 Say’s Pandora, 469, fig. 96b Say’s Tellin, 424 Scalas, see Wentletraps, 161 Scaled Worm-shell, 144, pl. 20e Scale-sided Piddock, 464 Scallop-edged Wentletrap, 162 Scallops, species of, 361-369 Scaly Chiton, see Rough Nuttall Chiton, 314 Schmitt’s Volute, 251, pl. 13e Schramm’s Chiton, 326, fig. 67e Schramn?’s Loripinus, see Chalky But- tercup, 390 Schwengel, J. S., 205, 414 Schwengel’s Venus, 414, pl. 38n Scientific names, 85 Scissor Date Mussel, 357, pl. 29; Scorched Mussel, 352, pl. 35j Scotch Bonnet, 192, pl. ge Screw Shell, see Turret-shell, 141 ae Sculpture in shells, 76, 84 Sculptured Alabine, 158 Sculptured Top-shell, 112, pl. 17w Sea Butterflies (Pteropoda), species of, 292 Sea-hares, species of, 285, fig. 60 Seaweed Limpet, 105, pl. 18z Semeles, species of, 434 Sennott, John and Gladys, 261 Sennotts’ Cone, 261, pl. 14h Sentis Scallop, 363, pl. 34a Sepia ink, 480 Serene Gould Clam, 415 Sex reversal, in snails, 25 in clams, 41 Sexuality, in snails, 25, fig. 7 in clams, 41 Shapes of bivalves, 80, fig. 26 Shapes of gastropods, 73 Shark Eye (Polinices), 186, pls. 5k, 22h Sharp-knobbed Nassa, 237, fig. 53c Sharp-ribbed Drill, 219, fig. 47¢ Sharp-turn Scallop, see Zigzag Scallop, 362 Shell Oil Company, 11 Shell structure, 33, fig. 10 Shell Transport Co., 10, 11 Shield Limpet, 102, pl. 18n Shiny Atlantic Auger, 266, pl. 26h Shiny Cooper’s Clam, 421 Shipping shells, 67 Shipworm, copulation, 42 destruction, 4 habits, 45 species of, 465 Short Coral-shell, 219 Short-frond Murex, see West Indian Murex, 203 Short-tailed Latirus, 241, pl. if Short Yoldia, 340, pl. 27b Shouldered Pheasant, 127, pl. 17r Sickle Razor Clam, see Blunt Jackknife Clam, 443 Silky Buccinum, 225, pl. 24u Simnias, species of, 182 Simpson’s Venus, 414 Single-toothed Simnia, 182, pl. 7e Siphonal canal, definition of, 76 Siphons, of clams, 35, figs. 11, 12 of snails, 18, fig. 3 Sitka Periwinkle, 134, pl. zob Slender Bittium, 156 Slipper-shells, species of, 170-172, pls. 20;n2t Slit-shells, g1 Slit Worm-shell, 145, pl. 21¢ Small Cerithium, see False Cerith, 153 Small-eared Lima, 371 Small False Donax, 441, pl. 30i Smith’s Martesia, 465 Smoke Shell, Longhorned, pl. 23w, not in text Smooth Astarte, 376, pl. 28s Smooth Atlantic Tegula, 118, pl. 17p Smooth Duck Clam, 449 > le: Smooth Giant Cockle, see Giant Pacific Egg Cockle, 400 Smooth Musculus, 355, pl. 28f Smooth Nut Clam, 335, fig. 70 Smooth Pacific Venus, 408, pl. 31k Smooth Panama Chiton, 325 Smooth Scotch Bonnet, 193, pl. of Smooth Tellin, 422, pl. 40k Smooth Velutina, 175, pl. 22n Smooth Washington Clam, 417 Smooth Western Nassa, 237, fig. 53f Snails, Life of, 16 Snowflake Marginella, 257, fig. 56m Snub-nose Corbula, 457 Soft-shell Clam, 455, pl. 32x Solander’s Trivia, 179, pl. zou Solarelles, species of, 110-111 Solid Surf Clam, see Atlantic Surf Clam, 446 Sombrero Lucina, 385, fig. 78b Sooty Sea-hare, 285 Southern Dwarf Astarte, 376 Southern Miniature Natica, 191, pl. 22} Southern Quahog, 406, pl. 32g Southern Spindle-bubble, 280 Sowerby’s Fleshy Limpet, 98, pl. 17h Sowerby’s Paper-bubble, 279 Sowerby’s Tusk, 331 Sozon’s Cone, 261, pl. 14¢ Spathate Scallop, 367 Species, definition of, 71 Speckled Tegula, 119, pl. 18v Speckled Tellin, 422, pl. 4o-l Spengler Clam, Atlantic, 460 Sphenia, Fragile, 455 Spindle-bubbles, species of, 280 Spindles, species of, 243 Spined Spindle-bubble, 281, pl. 26-1 Spiny Cockle, see Giant Pacific Cockle, 398 Spiny Cup-and-saucer, 170, fig. 7i Spiny Lima, 370, pl. 35¢ Spiny Margarites, species of, 109-110 Spiny Paper Cockle, 398, pl. 39n Spiny Periwinkle, see Beaded Peri- winkle, 134 Spiny Slipper-shell, 171, pl. 21q Spiral sculpture, definition of, 76 Spiral Shell, see Common Spirula, 478 Spirula, Common, 478, fig. 98 Spitzbergen Colus, 229, fig. 51h Splendid Top-shell, 116, pl. 33¢ Sponge Oyster, 374, pl. 28b Spoon Clams, species of, 472 Spotted Clam, see Calico Clam, 416 Spotted Limpet, 106 Spotted Northern Moon-shell, 1809, pl. 22m Spotted Periwinkle, pl. 19}, not in text Spotted Sea-hare, 285 Spotted Slipper-shell, 171 Spotted Thorn Drupe, 211, pl. 24-0 Squamose Chiton, 325 Squid, habits, 47 species of, 479 Index St. Martha’s Razor Clam, 445, pl. 30h St. Thomas Frog-shell, 197 Star Arene, 122 Star-shells, species of, 123 Stiff Pen Shell, 360, pl. 27x Stearns’ Cone, 262, pl. 22y Stearns’ Mussel, 353 Stearns’ Volute, 251 Stimpson’s Colus, 227, pl. 23x Stimpson’s Cone, 263, pl. 14} Stimpson’s Surf Clam, 446, pl. 31w; fig. 26k Stimpson’s Transennella, 412, fig. 83a, b Stimpson’s Tusk, 329 Stocky Cerith, 154, pl. 19-1 Stout Cardita, 379, pl. 29-1 Stout Tagelus, 440, pl. 30d Striate Bubble, 277, pl. 13p Striate Cup-and-saucer, 170, pl. 214r Striate Martesia, 464, pl. 32w Strigilla Clams, species of, 428 Striped False Limpet, 310, fig. 65 Stromboid notch, definition of, 76 Stuart’s Trophon, 207, pl. 24] Subgeneric names, 86 Suffuse Trivia, 177, pl. 21aa Sulcate Barrel-bubble, 280 Sulcate Limopsis, 347, pl. 27f Sun-dials, species of, 142 Sun-ray Shell, see Sunray Venus, 416 Sunray Venus, 416, pl. 39b Sunrise Tellin, 421, pl. goe Sunset Clam, see Californian Sunset Clam, 441 Superb Gaza, 118, pl. 3b Surf Clams, species of, 446-449 Swift’s Corbula, 458, fig. 93b Swimmer’s itch, 4 Swollen Egg Shell, see Flamingo Tongue, 183 Tabled Neptune, 231, fig. 51f Taenioglossate, 78 Tagelus, species of, 440 Tall-spired Turret, 271, fig. 57b Tampa Drill, 213 Tampa Tellin, 424, fig. 86b Tampa Urosalpinx, see Tampa Drill, 213 Tan Marginella, 254, fig. 56c Tantilla Transennella, 413 Taphria Nut Clam, 338, fig. 72a, b Tawny Murex, see Giant Eastern Mu- TeX, 203 Teardrop Marginella, 259, fig. 56-0 Tectibranchs, species of, 275 Teeth, in mouth, 79, figs. 6, 75 of shell material, 76, 84 Tegulas, species of, 118-121, pls. 3, 17, 18 Teinostomas, species of, 139 Tellin-like Cumingia, 436 Tellins, species of, 421-430 Ten-ridged Whelk, see Brown-corded Neptune. 229 Tenta Macoma, 431 Teredos, species of, 465 Tereinus Scallop, 363 Tessellate Nerite, 128, pl. 4f Test’s Limpet, 102, pl. 18g Texas Tusk, 329, fig. 69c Texas Venus, 416, pl. 32k; fig. 28c Textbooks on mollusks, 490 Thea Drillia, 270, fig. 57f Thick Buttercup, see Thick Lucina, 388 Thick-lipped Drill, 219, fig. 47b Thick Lucina, 388, pl. 38g Thick-ribbed Buccinum, 227, fig. 51b Thick-shelled Heart, see Pointed Venus, 409 Thin Nut Clam, 336, fig. 71a Thin Nut Shell, see Smooth Nut Clam, 335 Thin-shelled Littleneck, 410 % Thorn Drupes (Acanthina), 211 y Thorny Oysters, species of, 369, pl. 36 Thorny Scallop, see Sentis Scallop, 363. Thorny Slipper Shell, see Spiny Slip-_ per-shell, 171 # Thorson, Gunnar, 30 ( Thracias, species of, 471 Threaded Abalone, 93, pl. 2d Threaded Vitrinella, 138, pl. 17r Three-colored Top-shell, 113, fig. 33e Three-toothed Cardita, 380 Tides, 57 Tiger Cowrie, 7 Tiger Lucina, 390, pl. 38d Tile-roof Dog-avhelk, see Western Mud Nassa, 238 Tindaria, Brown, 341 ‘Tinted Cantharus, 232, pl. 25y Tollin’s Wentletrap, 164 Top-shells, species of, 112-117, fig. 33; pls. 3, 17 Tower-shell, see Turrets, 267 Toxoglossate, 79 Trade routes, 8, fig. 2 Trader Pyrene, see Common Dove- shell, 220 Transennellas, species of, 412 Transparent Razor Clam, 442 Transverse Ark, 345, pl. 27s Trapping mollusks, 59 Trellised Chiton, 323 Triangular Limpet, 104 Triangular Marginella, 258 Triangular Trophon, 208, fig. 46b Tridacna Clam, 37 Triforas, species of, 159 Tritons, species of, 194-197, pls. 9, 24, 25 Trivias, species of, 177-179, pls. 20, 21 Trophons, species of, 206-209, fig. 46 True Spiny Jewel Box, 394, pl. 37h True Tulip, 242, pl. 13b Trumpet Triton, 197, pl. sf Truncate Soft-shell Clam, 455, pl. 32v Truncated Angel Wing, see Fallen Angel Wing, 461 Tryon, George W., 68 Tryon’s Scallop, 366, pl. 33a Tucked Margarite, 109, fig. 31a Wulip Band Shell, see True Tulip, 242 Tulip Mussel, 351, pl. 35-1 \Tulips, species of, 242 Tuns, species of, 199 Turbans, species of, 123-126, pls. 3, 18 Turbine-shell, see Turbans, 123 __ {Turbonilles, species of, figs. 62, 63 ‘! Turkey Wing, 342, pl. 27n Turner, Ruth D., 68, 460 Turnip Spindle, 243, pl. 11g Turnip Whelk, 237, pl. 1a “\)Turrets (Turris), species of, 267-273 /Turret-shells (Turritella), 140-142 Tusk-shells, habits, 53 morphology, 54, fig. 19 species of, 327, fig. 69 }Two-kneeled Hairy-shell, 168, pl. 24a . Two-spotted Keyhole Limpet, 99, pl. h Dl 39 18e 3} Two-spotted Octopus, 488 'y Sip-§ Pwo-tinted Amphissa, 225 }Tyrian Purple Dye, 12 Umbilicus, definition of, 76 Umbo, definition of, 81 Umbrella Octopus, Common, 485 Uncinal teeth (radula), 79 Unequal Spoon Clam, 473, pl. 28x United States National Museum, 9, 68 Unstable Limpet, 105, pl. 18zz Uses of mollusks, 3 aie 3 ie rn Mud Value of shells, 6 Valve (bivalve shell), 81 Van der Schalie, H., 68 Vanhyning’s Cockle, go1, pl. 32b Vanikoro shell, 167 Variable Arene, 123, pl. 17s Variable Bittium, 155, pl. ror Variable Cerithium, see Dwarf Cerith, 154 Variable Dwarf Olive, 246, pl. 22v Variable Nassa, 239, pl. 23r Variable Top-shell, 116, fig. 33b Variable Wedge Shell, see Coquina Shell, 437 Variation in shells, 71 Variegated Dove-shell, 223 Variegated Lacuna, 131 Variegated Screw Shell, see Variegated Turret-shell, 141 Variegated Turret-shell, 141, pl. 211 Varix, definition of, 75 Vase Shell, 245 Vatikiotis, Sozon, 262 Veiled Pacific Chiton, 316, fig. 66a Velie’s Marginella, 258 Velutina, Smooth, 175, pl. 22n Venus Clams, species a 404-416 Venus-heart, see Astarte, 375 Verticord, Ornate, 474, fig. 97c, d Villepin’s Cone, 263, pl. 14f Violet Snails, see Purple Sea-snails, 160 fo 3 Uae $y Dove- Subject Matter and Common Names Virgin Marginella, 257, fig. 56h Virgin Nerite, 129, pl. 4i Virginia Oyster, see Eastern Oyster, 375 Virgulate Chiton, 325 Vitrinellas, species of, 138 Viviparity, 28, 42 Volcano Limpet, 100, pl. 18c Volute Turret, 273 Volutes, species of, 250 Walking Sea-hare, 286 Wart-necked Piddock, 436 Warty Cone, 263, pl. 22z Washington Clam, Common, 417, pl. 31-1 Washington Wood-eater, 463 Water glass, 59, fig. 20 Watson’s Canoe-bubble, 281, pl. 26m Watson’s Gaza, 118, fig. 32a Waved Astarte, 376, pl. 28r Wavy-lined Scallop, 367 Wavy Pacific Thracia, 472, pl. 31s Wavy Turban, 124, pl. 18p Weathervane Scallop, see Giant Pacific Scallop, 361 Wedge Clam, Arctic, 451, pl. 32r Wedge-shaped Martesia, 465 W edge-shell, see Donax, 437 Well-ribbed Dove-shell, 221, pl. 25ff Wentletrap, Precious, 6 Wentletraps, species of, 161-165, pl. 20, 22 West Coast Bittersweet, 349, pl. 31¢€ West Coast Rupellaria, 420, pl. 31t Western Atlantic Tusk, 329 Western Atlantic Wentletrap, 163 Western Baby’s Ear, 190 Western Banded Tegula, 120, pl. 18h Western Barrel-bubble, 281 Western Caecum, 149, fig. 37} Western Chubby Simnia, 183, pl. 7g Western Fat Nassa, 239, fig. 53e Western Lean Nassa, 240, fig. 53d Western Mud Nassa, 238, pl. 2on Western Pandora, 470 Western Ringed Lucina, 389, fig. 28f Western Three-winged Murex, 205, fig. 45C Western Tree Oyster, 358 Western White Slipper-shell, 172 West Indian Awning Clam, 333 West Indian Chank, 244 West Indian Crown Conch, 235, pl. 23h West Indian Cup-and-saucer, 169, pl. 21S West Indian Fighting Conch, 173, pl. sg West Indian Dwarf Olive, 246, pl. 1th, j West ea Murex, 203, pl. 10a West Indian Pointed Venus, 409 West Indian Tegula, 118 West Indian Top-shell, 117, fig. 34 West Indian Vanikoro, 167 West Indian Worm-shell, 144, fig. 221, pl. 21¢ 515 Whelks (Busycon), species of, 235-237 White Amiantis, see Pacific White Venus, 416 White Atlantic Doris, 302 White Atlantic Semele, 434, pl. gog White-banded Drillia, 270 White-barred Chiton, 317, fig. 67b White Bearded Ark, 342, pl. 27r White Cancellate Bittium, 156 White-cap Limpet, ror, pl. 18r White Crested Tellin, 430, pl. 30-0 White Dwarf Turban, 125 White Giant Turret, 268, pl. 13-1 White Globe Trivia, 179 White Hoof-shell, 166, pl. 2it White-knobbed Drillia, 271, fig. 574 White Miniature Ark, 343, pl. 27u White Northern Chiton, 322 White Pygmy Venus, 408 White Sandclam, see White Sand Ma- coma, 432 White Sand Macoma, 432, fig. 88c White Smooth-edged Jewel Box, 392 White-spotted Dove-shel!, 222, pl. 25hh White-spotted Engina, 232, pl. 25w White-spotted Latirus, 241, pl. 11e White-spotted Marginella, 256, pl. 11m White Strigilla, 429 Wide-mouthed Purpura, 14, 213, pl. 25-1 Willcox’s Sea-hare, 285 Wine-colored Auger, see Concave Au- er, 266 Winged Stromb, see Fighting Conch, 174 Winged Tree Oyster, see Flat Tree Oyster, 358 Wobbly Keyhole Limpet, ror, pl. 17g Wood-louse, Atlantic, 192, pl. 25s Woody Mopalia, 315 Worm-shells, species of, 143-145, pls. 20, 21 Woven Lucina, 388 Wrinkled Lepton, 395, fig. 80a Wrinkled-ribbed Wentletrap, 164 Writhing Shell, see Atlantic Distorsio, 196 Wroblewski’s Wentletrap, 162, pl. 20] Yellow Apolymetis, see Pacific Grooved Macoma, 434 Yellow Cockle, 397, pl. 39p Yellow False Doris, 306, pl. 15] Yellow Helmet, see Emperor Helmet, 193 Yellow Mussel, 352, pl. 351 Yellow-spotted Cowry, see Yellow Cowrie, 180 Yoldia-shaped Macoma, 433 Atlantic Zebra Cowrie, see Measled Cowrie, 180 Zebra Nerite, 129, pl. 4e Zebra Periwinkle, 132, pl. 19e Zebra Shell, see Zebra Nerite, 129 Zigzag Scallop, 362, pl. 33d Zoological Record (publication), 490 Index to Scientific Names This is a cross-index to subspecies, species, subgenera, genera and families. Names that are considered synonyms or homonyms have been entered in italics. abbreviata, Coralliophila, 219 abbreviata, Phalium, 193 Abra, 436 aequalis, 437, pl. 30v lioica, 437, pl. 30w profundorum, 32 Acanthina, 211 lapilloides, 211 paucilirata, 212 punctulata, 211 spirata, 211, pl. 24-0 Acanthinucella, 211 Acanthochitona, 318 astriger, 318 balesae, 318 pygmaeus, 318 spiculosus, 318 Acanthodoris, 305 brunnea, 306 pilosa, 305, 306, pl. 15b Acanthopleura, 314, 326 flexa, 314 granulata, 326 Acar, 343 Acephala, 332 acicula, Creseis, 294, fig. 64n acicularis, Neosimnia, 182, pl. 7a Acila castrensis, 336, fig. 72¢ Acirsa, 162 borealis, 162 costulata, 162 Aclididae, 160 Acmaea, 101-107 albicosta, 107 alveus, 105 antillarum, 106, pl. 17a asmi, 104 candeana, 106 conus, 102, 104, pl. 18g cribraria, 102, pl. 18w cubensis, 106 depicta, 104 digitalis, 102, 104, pl. 18f fenestrata, 102, pl. 18t fungoides, 107 insessa, 105, pl. 18z instabilis, 105, pl. 18zz jamaicensis, 106, pl. 18c leucopleura, 106, 310, pl. 17b limatula, 102, pl. 18-0 mitra, 1o1, pl. 18r paleacea, 105 patina, 104 pelta, 102, pl. 18n persona, 103, pl. 18q pulcherrima, 106 punctulata, 106 pustulata, 106 scabra, 102, 103, pl. 18-1 scutum, 103, 104 simplex, 106 Spectrum, 104 strigatella, 103 tenera, 106 tessulata, 104, 105 testudinalis, 104, 105 triangularis, 104 Acmaeidae, 101 acra, Turbonilla, 290, fig. 63c acrior, Ischnochiton, 321 acropora, Turritella, 141, pl. 21) Actaeon, see Acteon, 275 Acteocina, 281 candei, 280 cerealis, 282 culitella, 281 Acteocinidae, 281 Acteon, 275 candens, 275 punctocaelatus, 275 punctostriatus, 275, pl. 26t vancouverensis, 275 Acteonidae, 275 aculeata, Anomia, 372 aculeata, Crepidula, 171, pl. 21q aculeus, Cingula, 136 acuta, Crepidula, 171 acuta, Mopalia, 315 a7 acutilineatus, Phacoides, 389 acutus, Nassarius, 237, fig. 53e acutus, Rhizorus, 281, pl. 26-1 Adalaria proxima, 306, pl. 151 adamsi, Arcopsis, 343, 344, fig. 26b adamsi, Pyramidella, 290, fig. 63a adamsi, Seila, 158, pl. 22t adamsianus, Brachidontes, 353 adansonianus, Perotrochus, 92, pl. 3d Adapedonta, 442 adelae, Cancellaria, 252 Adesmacea, 460 Admete couthouyi, 253, fig. 55a adspersa, Lucapina, 98, pl. 17h Adula, 356 Aeolidia papillosa, 308, pl. 15g Aeolidiidae, 308 aepynota, Inodrillia, 271, fig. 57b aepynota, Odostomia, 290, fig. 63h aequalis, Abra, 436, pl. 30v aequalis, Neosimnia, 183 Aequipecten, 361, 366 borealis, 368 dislocatus, 368 exasperatus, 367 fusco-purpureus, 367 gibbus, 368, pl. 33) gibbus nucleus, 368, pl. 34h glyptus, 366, pl. 33a irradians, 367, pl. 331 irradians amplicostatus, 367 irradians concentricus, 368 lineolaris, 367 mayaguezensis, 367 muscosus, 364, 367, pl. 34d, e nucleus, 368 phrygium, 367 tryoni, 367 affinis, Bursa, 198 affinis, Cavolina, 296 affinis, Hyalaea, 296 affinis, Tagelus, 440 affinis, Tricolia, 126 agilis, Tellina, 422, pl. 30x; fig. 86f 518 Agriodesma, 469 Agriopoma, 416 Alabina, 158 diegensis, 159 tenuisculpta, 158 alaskana, Spisula, 447 alata, Isognomon, 358, pl. 35b alatus, Strombus, 174, pl. 5h alba, Anodontia, 389, pl. 38f alba, Cylichna, 282 alba, Murex, 205 albicosta, Acmaea, 107 albida, Homalopoma, 125 albida, Pitar, 414 albida, Polystira, 268, pl. 13-1 albinodata, Monilispira, 270 albocincta, Mitra, 249 albolineatus, Chiton, 325 albomaculata, Monilispira, 271, pl. 26f album, Tonna (Dolium), 199 albus, Ischnochiton, 313, 322 Aldisa sanguinea, 301 Aletes squamigerus, 144, pl. 20e algicola, Cerithium, 154, pl. 19p Allopora californica, 182 Aloidis, 457 alta, Apolymetis, 434 alta, Siliqua, 443 alternata, Diodora, 96 alternata, Siphonaria, 310, fig. 65a alternata, Tellina, 427, pl. gon alternatum, Bittium, 155 altispira, Melongena, 234 altus, Polinices, 187 alveus, Acmaea, 105 amabile, Cyclostrema, 121 amabile, Prunum, 256, fig. 56e Amaea, 163 mitchelli, 163, pl. 22f; fig. gob retifera, 163, fig. 4od Amaura, 290 Amauropsis, 187 islandica, 187, pl. 22r purpurea, 188 ambiguus, Nassarius, 239, pl. 23r; fig. 53a americana, Anadara, 345 americana, Argonauta, 485 americana, Astraea, 124, pl. 31 americana, Glycymeris, 349 americana, Odostomia, 290, fig. 63¢ americana, Volsella, 351, 352, pl. 35-1 americanus, Octopus, 487 americanus, Spondylus, 369, pl. 36b amianta, Gibberulina, 260 amianta, Odostomia, 290, fig. 63p Amiantis, 416 callosa, 416 nobilis, 417 amiantus, Lucina, 385, fig. 78c Amicula, 316 Amicula stelleri, 318, fig. 66d Amphineura, 312 Amphissa, 223 bicolor, 225 columbiana, 224, fig. sob Index undata, 224, fig. 50c versicolor, 223, 225, fig. 50a Amphithalamus, 136 inclusus, 136 lacunatus, 136 tenuis, 136 amphiurgus, Conus, 263 ampla, Panomya, 454 ampullacea, Volutharpa, 78 Amusium, 361, 362 amygdala, Bulla, 277 Amygdalum, 353 papyria, 353, pl. 281 sagittata, 353 Anachis, 221 avara, 221, pl. 25ee obesa, 221 ostreicola, 221 penicillata, 221 translirata, 221, pl. 25ff Anadara, 344 americana, 345 auriculata, 344 baughmani, 345 brasiliana, 346, pl. 27y campechiensis, 345 chemnitzi, 346 deshayesi, 344 grandis, 344 incongrua, 346 lienosa floridana, 344, pl. 27-0 multicostata, 344 notabalis, 344, pl. 27p ovalis, 345, pl. 27t pexata, 345 secticostata, 345 springeri, 345 sulcosa, 345 transversa, 345, pl. 27s Anatina Schumacher, 449 Ancistrolepsis, 230 Ancistrosyrinx, 268 elegans, 268 radiata, 268, fig. 57¢e Ancula, 306 cristata, 306, 307, pa. 15f pacifica, 307 sulphurea, 306 angulata, Cavolina, 296 angulata, Crassostrea, 374 angulata, Hyalaea, 296 angulatum, Epitonium, 164, 165, pl. 22b angulatus, Xancus, 244 angulifera, Littorina, 132, 133, pl. 19a angulosa, Tellina, 428 Angulus, 422 angusta, Fissurella, 100 Anisodoris, 299 anniae, Murex, 202 annulatum, Calliostoma, 115, fig. 33f annulatus, Phacoides, 389, fig. 28f annulatus, Spiroglyphus, 144 Annulicallus, 139 Anodontia, 389 alba, 389, pl. 38f chrysostoma, 389 philippiana, 389, pl. 38e schrammi, 390 Anomalocardia, 409 brasiliana, 409 cuneimeris, 409, pl. 39} Anomalodesmacea, 468 Anomia, 371 aculeata, 372 peruviana, 372, pl. 29e simplex, 372 Anomiidae, 371 Anopsia, 299 Antalis, see Dentale, 329 Antigona, 404 listeri, 404, pl. 32m rigida, 405 rugatina, 405, pls. 38m, 32n strigillina, 404, pl. 38-1; fig. 81d antillarum, Acmaea, 106, pl. 17a antillarum, Dentalium, 330 antillarum, Haminoea, 279 antillarum, Lithophaga, 357, 382, pl. 28k antillarum, Lyropecten, 366, pl. 34g antillarum, Trivia, 178 antillensis, Lima, 370 antillensis, Limopsis, 347 Antillophos candei, 231, pl. 25u antiquatus, Hipponix, 166, 168, pl. 21t Aperiploma, 474 apicinum, Prunum, 257, pl. 11n; fig. 56g apiculata, Chaetopleura, 319, figs. 67d, 68 Aplysia, 285 badistes, 286 dactylomela, 285 floridensis, 285 perviridis, 285 protea, 285 willcoxi, 285 Aplysidae, 285 Apolymetis, 434 alta, 434 biangulata, 434 intastriata, 434, pl. 32y Aporrhaidae, 173 Aporrhais, 173 labradorensis, 173 Mainensis, 173 occidentalis, 173, pl. 23¢ approximata, Lucina, 387, fig. 78g Aptyxis luteopicta, 244, fig. 54c aquitile, Cymatium, 195 aragoni, Turbonilla, 290, fig. 63k arborescens, Dendronotus, 307 Arca, 343 balesi, 343 occidentalis, 342 pernoides, 343 reticulata, 342 umbonata, 342, pl. 27j zebra, 342, pl. 27n arcella, Cirsotrema, 162 Archidoris, 299 montereyensis, 299, 301, pl. 16h nobilis, 300, 302, pl. 16c Architectonica, 142 granulata, 143 krebsi, 143, pl. 4-0; 21y nobilis, 142, 143, pl. 4m peracuta, 143, pl. qn; fig. 22g Architeuthis, 483 harveyi, 483, fig. 99c princeps, 483 Arcidae, 341 arcinella, Echinochama, 394, pl. 37h Arcopagia fausta, 428, pl. 40] Arcopsis adamsi, 343, 344, fig. 26b arctatum, Mesodesma, 451, pl. 32r Arctica islandica, 381, pl. 32f arctica, Hiatella, 452, fig. 92a arctica, Panomya, 453 arctica, Saxicava, 452 Arcticidae, 381 Arctomelon stearnsi, 251 arenaria, Mya, 41, 455, pl. 32x arenarius, Murex, 204 Arene, 122 cruentata, 122 gemma, 122, pl. 17q vanhyningi, 122 variabilis, 123, pl. 17s venustula, 122 arenosa, Lyonsia, 468 arenosa, Pandora, 470 Argina, 345 Arginarca, 345 argo, Argonauta, 485, pls. 1c, 26y Argobuccinum oregonense, 194, pl. 24g Argonauta, 485 americana, 485 argo, 485, pls. 1c, 26y hians, 485, fig. g9e, f aristata, Lithophaga, 357, pl. 29} armandina, Trivia, 177 Asaphis deflorata, 439, pl. 4oa asmi, Acmaea, 104 aspera, Diodora, 97, pl. 18b aspera, Mitromorpha, 273, fig. 57m aspinosus, Rhizorus, 281 asser, Cingula, 135 assimilis, Haliotis, 93, pl. 2d Astarte, 375 borealis, 375, pl. 28q castanea, 376, pl. 28s nana, 374 subequilatera, 375, 376, pl. 28-0 undata, 376, pl. 28r Astartidae, 375 Astraea, 123 americana, 124, pl. 3i brevispina, 123, pl. 3-1 caelata, 124, pl. 3h gibberosa, 125, fig. 35 guadeloupensis, 124 imbricata, 124 inaequalis, 125 longispina, 123, pl. 3k, m spinulosa, 123, pl. 3m tuber, 124, pl. 3] undosa, 124, pl. 18p Scientific Names Astralium, 123 astriger, Acanthochitona, 318 Astyris, 223 atacellana, Nucula, 335, fig. 70e Atlanta peroni, 184, fig. 41 atlantica, Charonia, 197 atlanticus, Glaucus, 309 atlanticus, Pleurobranchus, 286, fig. 61 Atlantidae, 184 atra, Polycera, 305, pl. 16¢e Atrina, 360 rigida, 360, pl. 27x serrata, 360, pl. 27Vv atropurpurea, Ocenebra, 217 attenuatum, Bittium, 156 Atydae, 278 Atys, 278 caribaea, 278, fig. 59c sandersoni, 278, fig. 59d aulaea, Haliotis, 93 aurantia, Catriona, 308, pl. 15] aureocincta, Marginella, 254, fig. 56b aureofasciatus, Conus, 260, pl. 14g aureotincta, Tegula, 120, pl. 18k auricula, Crucibulum, 169, pl. 21s auriculata, Anadara, 344 Aurinia, 251 auritula, Cantharus, 233 Austrotrophon, 200 avara, Anachis, 221, pl. 25ee avena, Hyalina, 258, pl. 11p; fig. 56i avena, Neosimnia, 183, pl. 7g avenacea, Hyalina, 259, fig. 56k avenella, Hyalina, 259 bacula, Homalopoma, 126 badistes, Aplysia, 286 baeri, Buccinum, 226, pl. 24v baetica, Olivella, 247, pl. 20q Bailya, 231 intricata, 231, pl. 25t parva, 231 bailyi, Barbatia, 343 bairdi, Calliostoma, 113, pl. 3-0 bairdi, Liotia, 121, pl. 17u bairdi, Lischkeia, 109, pl. 3c bakeri, Caecum, 150 bakeri, Rissoina, 137 balantium, Clio, 295 balea, Limacina, 292 balea, Spiratella, 292 balesae, Acanthochitona, 318 balesi, Arca, 343 balesi, Pseudomalaxis, 139 balthica, Macoma, 431, fig. 88g Bankia, 465 canalis, 467 caribbea, 466, fig. gs5e fimbriatula, 467, fig. o5f gouldi, 42, 466, figs. 16, 95d mexicana, 466 Bankiella, 466 Bankiopsis, 466 barbadensis, Fissurella, roo, pl. 17f barbadensis, Mitra, 249, pl. 26d ye) barbarensis, Fusinus, 244, pl. 24z barbarensis, Neosimnia, 183 Barbarofusus, 243 barbata, Barbatia, 343 Barbatia, 342 bailyi, 343 barbata, 343 cancellaria, 343, pl. 27q candida, 342, 343, pl. 27r domingensis, 343, pl. 27u helblingi, 343 jamaicensis, 343 tenera, 343, pl. 27k barbatus, Hipponix, 167 barkleyensis, Caecum, 148 Barnea, 460 costata, 41, 460, fig. 94a pacifica, 462 spathulata, 461 truncata, 461 barrattiana, Corbula, 458, fig. 93a bartrami, Sthenoteuthis, 484 Bartschella, 290 bartschi, Teredo, 467 Basommatophora, 310 Batillaria minima, 153, 155, pl. 19s baughmani, Anadara, 345 bayeri, Olivella, 18 beaui, Murex, 202, pl. 10d, g beaui, Vitrinella, 138 belcheri, Forreria, 200, pl. 24i bellastriata, Semele, 435, pl. 30) Bellucina, 385 bellum, Prunum, 256, fig. 56d benedicti, Chlamys, 363, 364 benthophila, Hipponix, 166 bequaerti, Murex, 205 Beringius, 227 beyerleana, Hyalina, 258 biarigulata, Apolymetis, 434 biangulata, Trigoniocardia, 399 bicarinata, Trichotropis, 168, pl. 24a bicincta, Neptunea, 230 bicolor, Amphissa, 225 bicolor, Isognomon, 358 bicolor, Murex, pl. 10m, not in text bidentata, Cylichna, 282, pl. 26q bifida, Janthina, 160 bifurcata, Tapes, 411 bifurcatus, Septifer, 353, 354 bilineata, Melanella, pl. 21w, not in text bilirata, Pandora, 471 bimaculata, Heterodonax, 441, pl. 301 bimaculatus, Megatebennus, 99, pl. 18e bimaculatus, Octopus, 488 bimaculoides, Octopus, 489 biplicata, Cylichna, 282 biplicata, Olivella, 247, pl. 12i biscaynensis, Teinostoma, 140 bisecta, Thyasira, 384, fig. 77a bispinosa, Melongena, 234 bispinosa, Peracle, 293, fig. 64f bisulcata, Lithophaga, 357, pl. 28n bisulcata, Torinia, 142, pl. 21x bisuturalis, Odostomia, 288, fig. 62h 520 bitruncata, Panope, 454 Bittium, 155 alternatum, 155 attenuatum, 156 eschrichti, 155, 156 interfossum, 156 montereyense, 156 quadrifilatum, 156 varium, 155, pl. ror virginicum, 155 bituberculatus, Strombus, 175 Bivalvia, 332 Bivetiella, 253 blakeana, Gymnobela, 273, fig. 57h Blepharopoda occidentalis, 396 bombix, Litiopa, 157 bombyx, Litiopa, 157 bonita, Haliotis, 92 borealis, Acirsa, 162 borealis, Aequipecten, 368 borealis, Astarte, 375, pl. 28q borealis, Marginella, 257 borealis, Onchidella, 275 borealis, Pranum, 257 borealis, Scalaria, 162 borealis, Solemya, 333 borealis, Trichotropis, 167, pl. 24d borealis, Venericardia, 379, 380, pl. 28t Boreomelon, 251 Boreotrophon, 206 clathratus, 206 dalli, 208, fig. 46a multicostatus, 207, 208, fig. 46c orpheus, 208, fig. 46e pacificus, 208, fig. 46f peregrinus, 208 scalariformis, 207 scitulus, 207, fig. 46d smithi, 207 stuarti, 207, pl. 24] triangulatus, 208, fig. 46b Bornia longipes, 396, fig. 80, not in text Botula, 356 californiensis, 356, pl. zgh falcata, 356, pl. 29k fusca, 356 Brachidontes, 352 adamsianus, 353 citrinus, 352, 353, pl. 351 exustus, 352, pl. 35) hamatus, 353 multiformis, 353 recurvus, 351, 353, pl. 35n stearnsi, 353 brandaris, Murex, 12, pl. 10] branhamae, Fasciolaria, 242 brasiliana, Anadara, 346, pl. 27y brasiliana, Anomalocardia, 409 brasiliana, Crassostrea, 375 brasiliana, Tonna, 199 brasiliensis, Iphigenia, 439, pl. 32u brevicaudatus, Latirus, 241, pl. rf brevifrons, Murex, 203, pl. 10a brevipinna, Lolliguncula, 482 brevis, Lolliguncula, 482, fig. 99g Index brevispina, Astraea, 123, pl. 3-1 briareus, Octopus, 487, fig. 100c bronniana, Limea, 371 brota, Macoma, 433, fig. 88a browniana, Rissoina, 137 brunnea, Acanthodoris, 306 brunnea, Tegula, 119, 120 brunnea, Tindaria, 341 brunneus, Polinices, 186, pl. 5] bryerea, Rissoina, 137 Buccinidae, 223 (note), 225 Buccinum, 225 baeri, 226, pl. 24v glaciale, 226, pl. 24t plectrum, 225, fig. 50a tenue, 225, 226, pl. 24u undatum, 225 Bufonaria, 198 bulimoides, Spiratella, 293, fig. 64d Bulla, 277 amygdala, 277 gouldiana, 278 occidentalis, 277, pl. 26p punctulata, 278 striata, 277, pl. 13p Bullaria, see Bulla, 277 Bullidae, 277 Bursa, 197 affinis, 198 caelata, 198 californica, 199, pl. 2or corrugata, 198, pl. 9k crassa, 198 cubaniana, 198 granularis, 198, pl. 25-0 louisa, 198 ponderosa, 198 spadicea, 198, pl. 25p tenuisculpta, 198 thomae, 197 Bursatella leachi plei, 286 burryi, Murex, 203 burryi, Octopus, 487, fig. roob bushi, Rhizorus, 281 bushiana, Pandora, fig. 96a, not in text Busycon, 235 canaliculatum, 236, pl. 23n carica, 235, 236, pl. 231 coarctatum, 237, pl. 1a contrarium, 76, 236, pl. 23-0 Rieneri, 236 perversum, 236, pl. 23k plagosum, 237 pyrum, 236 spiratum, 236, pl. 9g Busycotypus, 236 butleri, Scaphella, 250 buttoni, Tellina, 425 buttoni, Turbonilla, 290, fig. 63d cabriti, Murex, 201, pl. roh Cadlina, 301 flavomaculata, 302 laevis, 302 marginata, 302 obvelata, 302 planulata, 302 repanda, 302 Cadulus, 150, 327 carolinensis, 327, fig. 69a mayori, 328 quadridentatus, 328 caeca, Lepeta, 107, pl. 17] Caecidae, 145 Caecum, 146 bakeri, 150 barkleyense, 148 californicum, 147, fig. 37g carolinianum, 149, fig. 37¢ carpenteri, 148, fig. 371 catalinense, 148 cayosense, 147 cooperi, 148, fig. 37g crebricinctum, 147, fig. 37m dalli, 147, fig. 37h diegense, 147 floridanum, 146, fig. 372 grippi, 147 hemphilli, 150 heptagonum, 148, fig. 37k lermondi, 150 licalum, 147 nebulosum, 149, fig. 37f nitidum, 150, fig. 37e occidentale, 149, fig. 37] orcutti, 149, fig. 37-1 oregonense, 148 pedroense, 148 pulchellum, 147, fig. 37d rosanum, 148 caelata, Astraea, 124, pl. 3h caelata, Bursa, 198 caelatus, Colus, 229 caelatus, Pyrunculus, 280, pl. 26w calamus, Dentalium, 331 calcarea, Macoma, 430, fig. 88f californiana, Trivia, 179, pl. 20v californianus, Mytilus, 354, pl. 29p californianus, Nassarius, 239 californianus, Tagelus, 440, pl. 29u californica, Allopora, 182 californica, Bursa, 199, pl. zor californica, Codakia, 390, pl. 31¢ californica, Cryptomya, 456 californica, Cumingia, 436, pl. 31v californica, Donax, 438, pl. 31p californica, Echinochama, 394, pl. 37e californica, Hyalina, 259 californica, Lyonsia, 468 californica, Mactra, 445, fig. 90d californica, Neptunea, 230 californica, Nuttallina, 314 californica, Parapholas, 464 californica, Pedicularia, 182, pl. 7b, c californica, Rissoina, 137 californica, Rupellaria, 421 californicum, Caecum, 147, fig. 37g californicum, Sinum, 190 californicus, Capulus, 168 californicus, Conus, 265 californicus, Ensis, 443 californiensis, Botula, 356, pl. 29h californiensis, Chione, 407, pl. 31) californiensis, Glossodoris, 303 californiensis, Haliotis, 92 californiensis, Ischnochiton, 323 californiensis, Rupellaria, 420 Callianax, 247 Calliostoma, 112 annulatum, 115, fig. 33f bairdi, 113, pl. 3-0 canaliculatum, 115 doliarium, 115, 116, pl. 3q; fig. 33h euglyptum, 112, pl. 17w gemmulatum, 115, fig. 33d gloriosum, 116, fig. 33a jujubinum, 113, pl. 3p ligatum, 116, fig. 33g occidentale, 113 psyche, 113 pulchrum, 112 roseolum, 112 splendens, 116, fig. 33¢ subumbilicatum, 113 supragranosum, 115, pl. 18s tampaense, 113 tricolor, 113, fig. 33¢€ variegatum, 116, fig. 33b zonamestum, 112, pl. 3n Calliotropis, 109 Callista eucymata, 415, pl. 391 Callocardia texasiana, 416, pl. 32k; fig. 28e Callogaza, 118 callomarginata, Lucapinella, 99, pl. 18d Calloplax janeirensis, 319, fig. 67¢ callosa, Amiantis, 416 Calyptraea, 169 candeana, 169 centralis, 169, pl. 21-0 contorta, 169 fastigiata, 169, pl. 20-1 Calyptraeidae, 169 campechensis, Raeta, 449 campechiensis, Anadara, 345 campechiensis, Mercenaria, 406, pl. 32g campechiensis, Pholas, 462, pl. 32t canaliculata, Raeta, 449 canaliculata, Retusa, 280, pl. 26x canaliculata, Thais, 216, fig. 48b, c canaliculatum, Busycon, 236, pl. 23n canaliculatum, Calliostoma, 115 canaliculatus, Strombus, 174 canaliculatus, Turbo, p. 123, pl. 3a canalis, Bankia, 467 Cancellaria, 252 adelae, 252 conradiana, 252 crawfordiana, 252, fig. 5sb reticulata, 252, pl. 13k cancellaria, Barbatia, 343, pl. 27q cancellaria, Cantharus, 234 Cancellariidae, 252 cancellata, Chione, 173, 407, pl. 39h cancellata, Herse, 299 Scientific Names cancellata, Lucapina, 98 cancellata, Nucula, 335 cancellata, Rissoina, 137 cancellata, Semele, 435 cancellata, Trichotropis, 167, pl. 24b cancellatum, Cyclostrema, 121 cancellatus, Lepidopleurus, 312 cancellatus, Platyodon, 456 candeana, Acmaea, 106 candeana, Calyptraea, 169 candeana, Tellina, 427 candei, Acteocina, 280 candei, Antillophos, 231, pl. 25u candei, Retusa, 280 candens, Acteon, 275 candida, Barbatia, 342, 343, pl. 27r candidula, Trivia, 178, pl. 21cc canrena, Natica, 191, pl. 5-l Cantharus, 233 auritula, 233 cancellaria, 234 tinctus, 214, 233, 234, pl. 25y capax, Schizothaerus, 450 capax, Volsella, 352 Capulidae, 168 Capulus, 168 californicus, 168 incurvatus, 168 intortus, 168 carchedonius, Modulus, 151 Cardiidae, 397 Cardiomya, 476 costellata, 476 gemma, 476 multicostata, 476 pectinata, 477 Cardita, 378 carpenteri, 378, pl. 29r dominguensis, 378, 380 floridana, 378, pl. 30a gracilis, 378 Carditamera, 378 Carditidae, 378 carditoides, Rupellaria, 421 Cardium, 37! caribaea, Atys, 278, fig. 59¢ caribaea, Lima, 370 caribaeum, Xenophora, 173 caribbea, Bankia, 466, fig. 95¢€ carica, Busycon, 235, 23, pl. 231 Carinaria, 185 lamarcki, 185, fig. 42 mediterranea, 185 Carinariidae, 185 carinata, Lacuna, 131, fig. 36a carinata, Nitidella, 222 carlottensis, Macoma, 433 carnaria, Strigilla, 428, pl. goc carnea, Pinna, 360, pl. 27w carnea, Primovula, 181, pl. 22q carneum, Prunum, 254, 256, pl. 11k carolae, Ficus, 200 carolinensis, Cadulus, 327, fig. 69a carolinensis, Octopus, 487 carolinensis, Pandora, 470 521 carolinensis, Sigatica, 187, pl. 22-1 caroliniana, Polymesoda, 381, pl. 30bb carolinianum, Caecum, 149, fig. 37¢ carpenteri, Caecum, 148, fig. 371 carpenteri, Cardita, 378, pl. 29r carpenteri, Homalopoma, 126, pl. 181 carpenteri, Murex, 205, fig. 45c carpenteri, Nuculana, 337 carpenteri, Onchidella, 274 carpenteri, Tellina, 426 carpenteri, Triopha, 304, pl. 16k Cassididae, 192 Cassis, 192 flammea, 193 madagascariensis, 193, pl. 23v spinella, 194 tuberosa, 193 castanea, Astarte, 376, pl. 28s castaneus, Lioberus, 356 castaneus, Turbo, 123, pl. 3g castaneus, Volutopsius, 226, fig. 51¢ castrensis, Acila, 336, fig. 72¢ catalinense, Caecum, 148 catalinensis, Neosimnia, 183 catenata, Persicula, 257, fig. 56] catilliformis, Spisula, 448, fig. goc Catriona, 308 aurantia, 308, pl. 15] aurantiaca, 309 caudata, Eupleura, 219, fig. 47b caurinus, Pecten, 361, pl. 29b Cavolina, 296 affinis, 296 angulata, 296 costata, 298 cuspidata, 298 elongata, 298 gibbosa, 296, fig. 64w imitans, 298 inermus, 298 inflexa, 298, fig. 64r intermedia, 298 labiata, 298 limbata, 298 longirostris, 296, pl. 64v minuta, 298 mucronata, 298 quadridentata, 298, fig. 64s reeviana, 298 telemus, 296 tridentata, 296, fig. 64u trispinosa, 298, fig. 64t uncinata, 298, fig. 64x uncinatif ormis, 298 Cavolinia, see Cavolina, 296 Cavolinidae, 294 cayenensis, Diodora, 96, pl. 17m cayosense, Caecum, 147 cellulosus, Murex, 204, fig. 45b Cenchritis, 134 centifilosum, Nemocardium, 399 centiquadrata, Phalium, 193 centralis, Calyptraea, 169, pl. 21-0 centrifuga, Phacoides, 389 Cephalopoda, 478-489 D2 cepio, Pododesmus, 372 Cerastoderma, pinnulatum, 404, pl. 30c Ceratostoma foliatum, 219 Ceratozona rugosa, 317, 326, fig. 67a cerealis, Acteocina, 282 cerina, Gouldia, 415 cerinella, Cingula, 135 Cerithidea, 151 costata, 152, pl. 19u hegewischi californica, 152 pliculosa, 152, pl. r9t scalariformis, 152, pl. 19x turrita, 152 Cerithideopsis, 152 Cerithiopsis, 157 carpenteri, 157 emersoni, 157 greeni, 157, pl. 19v grippi, 158 pedroana, 158 subulata, 157, pl. 19w vanhyningi, 157 virginica, 157 Cerithium, 153, 270 algicola, 154, pl. 19p eburneum, 154, pl. 19q floridanum, 153, pl. 19n literatum, 154, pl. 19-1 muscarum, 154, pl. 19m variabile, 154, pl. 19-0 versicolor, 154 Cerodrillia, 270 perryae, 270 thea, 270, fig. 57f cerrosensis, Forreria, 200, fig. 44a, b cervus, Cypraea, 180, pl. 6f cestum, Dentalium, 329 chacei, Opalia, 162 Chaetopleura apiculata, 319, figs. 67d, 68 Chama, 391, 392 congregata, 392, pl. 37d firma, 393 macerophylla, 392, fig. 79b; pl. 37b sinuosa, 392, fig. 79a Chamidae, 391 Charonia, 197 atlantica, 197 tritonis, 197 tritonis nobilis, 197, pl. 5f Cheila equestris, 165, pl. 21p chemnitzi, Anadara, 346 Chemnitzia, 290 chemnitziana, Isognomon, 358 chesneli, Rissoina, 137 Chicoreus, 203 Chione, 407 californiensis, 407, pl. 31] cancellata, 173, 407, pl. 39h fluctifraga, 408, pl. 31k gnidia, pl. 31d, not in text grus, 408, pl. 321 intapurpurea, 407, pl. 39g interpurpurea, 407 latilirata, 409, pl. 39¢ mazycki, 407 Index paphia, 4o9, pl. 39a pygmaea, 408 succincta, 408 undatella, 408, pl. 311 Chionidae, 404 Chiton, 324 albolineatus, 325 laevigatus, 324 marmoratus, 324, 325 squamosus, 324, 325 stokesi, 326 tuberculatus, 324, pl. 1d; fig. 67f virgulatus, 324 viridis, 325 Chitonidae, 324 Chlamys, 361, 363, 368 benedicti, 363, 364 hastatus, 364, pl. 34j hericius, 364, pl. 34k hindsi, 365, pl. 34-1 imbricatus, 364, pl. 34f islandicus, 365, pl. 24-1 mildredae, 363, pl. 34c ornatus, 363, pl. 34b sentis, 363, 364, pl. 34a Chlorostoma, 120 chlorostomum, Cymatium, 195, 196, pl. 25 ; cocaine Turbonilla, 290, fig. 63e Chrysallida, 288, 290 Chrysodomus lirata, 230 chrysostoma, Lucina, 389 cicatricosum, Phalium, 198, pl. of Cidarina, 109 cidaris, Lischkeia, 109, fig. 31h ciliata, Mopalia, 315, 316 ciliatum, Clinocardium, 403, pl. 32¢ cinerea, Cypraea, 180, pl. 6c cinerea, Terebra, 266, pl. 26g cinerea, Urosalpinx, 212, fig. 47¢e cinereum, Gastropteron, 285 cinereus, Margarites, 107 Cingula, 135 aculeus, 136 asser, 135 cerinella, 135 kelseyi, 135 kyskensis, 135 montereyensis, 135 palmeri, 135 cingulifera, Leucozonia, 241 Circinae, 415 Circomphalus, 404 Circulus, 138 circumtexta, Ocenebra, 218, fig. 49b Cirsotrema, 161 arcella, 162 dalli, 161, fig. goa; pl. 22¢ cistula, Lasaea, 353, 395 citrica, Ocenebra, 218 citrinus, Brachidontes, 352, 353, pl. 351 citrinus, Conus, 262 citrinus, Murex, 202 Cittarium, 117 clarki, Conus, 264, pl. 141 clathrata, Distorsio, 196, pl. 25aa clathrata, Ocenebra, 217 clathrata, Peracle, 293 clathratus, Boreotrophon, 206 clathratus, Ischnochiton, 323 clathrum, Epitonium, 165 clausa, Natica, 191, fig. 43b clavium, Teinostoma, 140 cleo, Rissoina, 137 Cleodora, 294, 295 Clinocardium, 403 ciliatum, 403, pl. 32e corbis, 403 fucanum, 403 nuttalli, 403, pl. 31b Clio, 295 balantium, 295 cuspidata, 295, fig. 64i exacuta, 295 falcata, 295 lanceolata, 295 polita, 295, fig. 64-1 pyramidata, 295, fig. 64k recurva, 295, fig. 64] clione, 299 Clionopsis, 299 Cliopsis, 299 Clypidella, rox coarctata, Cumingia, 436 coarctatum, Busycon, 237, pl. 1a Cochlodesma, 474 cockerelli, Laila, 304, pl. 16} cocolitoris, Teinostoma, 139 Codakia, 390 californica, 390, pl. 31¢ costata, 390, filiata, 391 orbicularis, 390, pl. 38d orbiculata, 391, pl. 30-1 coestus, Vasum, 245 Collisella, 102 Colubraria, 232 lanceolata, 232, pl. 25x swifti, 233 testacea, 233 Colubrellina, 198 Columbella, 220 mercatoria, 220, pl. 25bb rusticoides, 220 columbella, Erato, 176 Columbellidae, 220 columbiana, Amphissa, 224, fig. sob columbiana, Crenella, 351, fig. 26g, h columnella, Herse, 299, fig. 64m Colus, 227 caelatus, 229 pubescens, 229, pl. 23t pygmaeus, 229, pl. 23m spitzbergensis, 229, fig. 51h stimpsoni, 227, pl. 23x ventricosus, pl. 23u, not in text colymbus, Pteria, 359, pl. 35d commune, Epitonium, 164 communis, Ficus, 200, pl. 9i compressa, Pseudopythina, 395 ath | Compsomyax subdiaphana, 411, pl. 31f _ compta, Tricolia, 127 _ concava, Terebra, 266, pl. 26] concentrica, Ervilia, 452 _ concentrica, Nuculana, 338 conceptionis, Nuculana, 336 _conchaphila, Ostrea, 374 _conchyliophora, Xenophora, 173, pl. 5b | concinna, Tricolia, 127 _ Congeria leucophaeta, 382 | congregata, Chama, 392, pl. 37d | conica, Creseis, 294 _ conica, Styliola, 294 _ Conidae, 260 | coniformis, Creseis, 294 _ conradi, Thracia, 471, pl. 28y conradiana, Cancellaria, 252 _ conradina, Transennella, 413, fig. 83¢ consensus, Nassarius, 239, fig. 53b conspicuus, Ischnochiton, 321 _ constricta, Distorsio, 197 _ constricta, Macoma, 432 | contorquata, Epitonium, 163 contorta, Calyptraea, 169 contracta, Corbula, 457 contrarium, Busycon, 236, pl. 23-0 - Conus, 260 amphiurgus, 263 aureofasciatus, 260, pl. 14g austini, 264 californicus, 265 citrinus, 262 clarki, 264, pl. 14i daucus, 260, pl. 14a floridanus, 261, pl. 14d floridanus burryae, 261 floridensis, 261, pl. 14 frisbeyae, 264 granulatus, 264, pl. 14-1 jaspideus, 262, pl. 1qn; 22x juliae, 261, pl. 14b mazei, 264, pl. 14k mus, 262, pl. 14-0 peali, 263 sennottorum, 261, pl. 14h regius, 262, pl. 14m sozoni, 261, pl. 14¢ spurius atlanticus, 260, pl. 14p spurius spurius, 260 stearnsi, 262, pl. 22y stimpsoni, 263, pl. 14] vanhyningi, 263 verrucosus, 263, pl. 22z villepini, 263, pl. 14f conus, Acmaea, 102, 104, pl. 18g convexa, Crepidula, 171, pl. 21n cookeana, Cyclostrema, 122 cookeana, Liotia, 122 Cooperella subdiaphana, 421 cooperi, Caecum, 148, fig. 37b cooperi, Ischnochiton, 323 cooperi, Narona, 253, pl. 24y; fig. sse cooperi, Nassarius, 240 cooperi, Turritella, 141, 142, pl. 20g Scientific Names Coralliophaga coralliophaga, 382, pl. 28 Coralliophila, 219 abbreviata, 219 costata, 220 deburghiae, 220 hindsi, 220 Corbiculiidae, 381 corbis, Cardium, 403 Corbula, 457 barrattiana, 458, fig. 93a contracta, 457 dietziana, 457 disparilis, 456, 457 luteola, 459 nasuta, 457 porcella, 459 rosea, 459 swiftiana, 458, fig. 93b Corbulidae, 456 cordata, Pitar, 414, pl. 38n cornuta, Echinochama, 394, pl. 37g corona, Melongena, 234, fig. 52 coronadoensis, Rissoina, 137 corrugata, Bursa, 198, pl. 9k corrugata, Haliotis, 93, pl. 2c Coryphella rufibranchialis, 310, pl. 15a Costacallista, 415 costalis, Margarites, 107, 110, pl. 17t costata, Barnea, 460, fig. 94a costata, Cavolina, 298 costata, Cerithidea, 152, pl. rou costata, Codakia, 390 costata, Coralliophila, 220 costata, Siliqua, 442, pl. 30f costatus, Strombus, 174, pl. 23b costellata, Cardiomya, 476 costulata, Acirsa, 162 couei, Fusinus, 268, pl. 13d couthouyi, Admete, 253, fig. 55a cracherodi, Haliotis, 92, pl. 2f cranoides, Hipponix, 166 crassa, Bursa, 198 Crassatella, 377 Crassatellidae, 376 Crassatellites, 377 crassatelloides, Tivela, 412 Crassinella, 377 lunulata, 377, fig. 28k mactracea, 377, pl. 30b Crassispira, 268 ebenina, 268, fig. 57} ostrearum, 270, pl. 26n sanibelensis, 270 tampaensis, 270 Crassispirella, 270 Crassostrea, 374 angulata, 374 brasiliana, 375 floridensis, 375 gigas, 41, 374, 375, pl. 20g laperousi, 375 rhizophorae, 374, 375 virginica, 373, 375, pl. 28a Cratena, 308 523 crawfordiana, Cancellaria, 252, fig. 55b crebricinctum, Caecum, 147, fig. 37m crebricostata, Jumala, 227, fig. 51b Cremides, 100 crenata, Opalia, 162 Crenella, 349, 354 columbiana, 351, fig. 26g, h decussata, 350 divaricata, 350 faba, 350, fig. 75a glandula, 350, fig. 75b, c; pl. 28} crenella, Lucina, 387 crenimarginata, Opalia, 163 crenulata, Megathura, gg, pl. 18a crenulata, Nucula, 335 crenulatus, Turbo, 123 Crepidula, 170 aculeata, 171, pl. 21q acuta, 171 convexa, 171, pl. 21n excavata, 172 fornicata, 25, 28, 172, pl. 21m; fig. 7h glauca, 171 maculosa, 171 nummaria, 172 onyx, 171, pl. 2of plana, 172 Crepipatella lingulata, 170, pl. 20k Creseis, 294 acicula, 294, fig. 64n conica, 294 coniformis, 294 virgula, 294, fig. 64p vitrea, 294 cribraria, Acmaea, 102, pl. 18w cribraria, Nitidella, 222 crispata, Purpura, 215 crispata, Scissurella, 91 crispata, Thais, 215 crispata, Zirfaea, 462, fig. g4c cristata, Ancula, 306, 307, pl. 15f cristata, Limopsis, 347 cristata, Ostrea, 373 cristata, Tellidora, 430, pl. 30-0 Crossata, 199 crosseanum, Eudolium, 199, pl. 23g Crucibulum, 169 auricula, 169, pl. 21s spinosum, 25, 170, fig. 7i striatum, 169, 170, pl. 21r crucifera, Fissurella, 101 cruenta, Sanguinolaria, 439, pl. god cruentata, Arene, 122 Cryptochiton stelleri, 318, 319 Cryptoconchus floridanus, 317, fig. 67b Cryptomya californica, 456 Cryptonatica, 191 Cryptoplacidae, 317 cryptospira, Teinostoma, pl. 17y, not in text Ctena, 391 Ctenoides, 370 cubana, Sthenorytis, 161 cubaniana, Bursa, 198 cubensis, Acmaea, 106 524 cucullata, Puncturella, 96, fig. 30a, b culitella, Acteocina, 281 Cumingia, 436 californica, 436, pl. 31v coarctata, 436 tellinoides, 436 vanhyningi, 436 cumingianus, Solecurtus, 444 Cunearca, 346 cuneata, Rangia, 450, fig. 91 cuneiformis, Martesia, 465 cuneiformis, Rocellaria, 459, 460 cuneimeris, Anomalocardia, 409, pl. 39} curta, Thracia, 472 curtulosa, Nuculana, 337 Cuspidaria, 475 glacialis, 475, fig. 97b granulata, 476 jeffreysi, 475 rostrata, 476, pl. 32] cuspidata, Cavolina, 298 cuspidata, Clio, 295, fig. 641 Cuvieria, 299 Cuvierina, 299 Cyanoplax, 313 Cyathodonta, 472 dubiosa, 472 pedroana, 472 undulata, 472, pl. 31s Cyclocardia, 379 Cyclostrema, 121 amabile, 121 cancellatum, 121 cookeana, 122 Cyclotellina, 428 Cylichna, 282 alba, 282 bidentata, 282, pl. 26q Cylichnella, 282 cylindrica, Torinia, 142 Cymatiidae, 194 Cymatium, 195 aquitile, 195 chlorostomum, 195, 196, pl. 25q cynocephalum, 196, pl. 9j femorale, 195, pl. 5d gracile, 195, 196, pl. 25n labiosum, 196, pl. 25m martinianum, 195, 196, pl. 9-1 muricinum, 196, pl. 25r pileare, 195 tuberosum, 196 prima, 195 velei, 195 cymbiformis, Haminoea, 279 cynocephalum, Cymatium, 196, pl. 9j Cyphoma, 183 gibbosum, 183, pl. 8; pl. qr mecgintyi, 184, pl. 8; pl. 4s signatum, 184, pl. 4t Cypraea, 177, 180 cervus, 180, pl. 6f cinerea, 180, pl. 6c exanthema, 180 moneta, 7 Index mus, 181, pl. 6e pantherina, 7 spadicea, 180, pl. 6b spurca, 180 spurca acicularis, 180, pl. 6a tigris, 7 vallei, 180 zebra, 180, pl. 6d Cypraecassis, 194 rufa, 7 testiculus, 194, pl. 9c Cypraeolina, 259 Cyprina, 381 Cyrtodaria, 453 kurriana, 453 siliqua, 453 dactylomela, Aplysia, 285 dalli, Boreotrophon, 208, fig. 46a dalli, Caecum, 147, fig. 37h dalli, Cirsotrema, 161, pl. 22c, fig. 4oa dalli, Rissoina, 137 Daphnella lynneiformis, 273 daucus, Conus, 260, pl. 14a debile, Sinum, 190 debilis, Diaphana, 277 deburghiae, Coralliophila, 220 Decapoda, 478 decemcostata, Neptunea, 229, pl. 23s decipiens, Pododesmus, 372 decisa, Semele, 435, pl. 29z decora, Yellina, 426 decorata, Triphora, 159, pl. 192z decussata, Crenella, 350 decussata, Glycymeris, 348, pl. 27h decussata, Pedicularia, 181, pl. 7d decussata, Rissoina, 137 dehiscens, Lima, 371 delicatus, Murex, 202 delphinodonta, Nucula, 335, fig. 70 deltoidea, Thais, 214, pl. 25b, k demissa, Volsella, 351, pl. 38h demissa granosissima, Volsella, 352 Dendrodorididae, 303 Dendrodoris fulva, 303 Dendronotidae, 307 Dendronotus, 307 arborescens, 307 frondosus, 307, pl. 15e giganteus, 307 densiclathrata, Diodora, 98 Dentale, 329 Dentaliidae, 328 Dentalium, 328 antillarum, 330 calamus, 331 cestum, 329 eboreum, 331, fig. 69e elephantinum, 55 entale, 329 entale stimpsoni, 328 filum, 331 floridense, 330 laqueatum, 328 megathyris Dall, pl. 1e, not in text occidentale, 329 pilsbryi, 330, fig. 69d pretiosum, 330, fig. 6of pseudohexagonum, 330 semiostriolatum, 331 sowerbyl, 331 texasianum, 329, fig. 69e dentata, Divaricella, 391 denticulata, Donax, 438, pl. 30p denticulata, Marginella, 254, fig. 56c denticulata, Rupellaria, 420 dentiens, Lepidochitona, 313, 314 Dentilucina, 388 Dentiscala, 162 depicta, Acmaea, 104 deshayesi, Anadara, 344 despectus, Tergipes, 309, pl. 15d Diacria, 298 Diadora, 96 Diaphana, 277 debilis, 277 hiemalis, 277 globosa, 277 | minuta, 277, fig. 59b | Diaphanidae, 277 Diastomidae, 158 Diaulula sandiegensis, 301, pl. 16d Diberus, 357 Dibranchia, 478 diegense, Caecum, 147 diegensis, Alabina, 159 diegensis, Limopsis, 347, fig. 73 diegensis, Pecten, 169, 361, pl. 33e diegensis, Teredo, 467 diegoensis, Haliotis, 93 diegoensis, Lamellaria, 175, fig. 43d dietziana, Corbula, 457 | digitalis, Acmaea, 102, 103, pl. 18f Dinocardium, 401 robustum, qor, pl. 32a q vanhyningi, gor, pl. 32b Diodora, 96 alternata, 96 aspera, 97, pl. 18b cayenensis, 96, pl. 17m densiclathrata, 98 dysoni, 97, pl. 17n listeri, 96, pl. 17-1 minuta, 97 murina, 98 diomedea, Rubellatoma, 272 dione, Pitar, 415, pl. 39f Diplodonta, 383, 391 granulosa, 383 orbella, 383 punctata, 383 semiaspera, 383 subquadrata, 383 Diplodontidae, 383 dira, Searlesia, 232, fig. 50d | directus, Ensis, (35), 443, pl. 30k; fig. 11d Dischides, 327 Discodoris heathi, 300, pl. 16-i discors, Musculus, 355, pl. 28e discus, Dosinia, 417, fig. 81¢ discus, Periploma, 473, figs. 97a; 28-l disjuncta, Thyasira, 385 dislocata, Terebra, 265, pl. 26-1 dislocatus, Aequipecten, 368 disparilis, Varicorbula, 457 Dispotaea, 170 Dissentoma prima, 195 distans, Fasciolaria, 242 Distorsio, 196 clathrata, 196, pl. 25aa constricta, 197 constricta megintyi, 197, pl. 252 floridana, 197 divaricata, Crenella, 350 divaricata, Lacuna, 131 Divaricella, 391 dentata, 391 quadrisulcata, 391, pl. 30m divisus, Tagelus, 440, pl. 30g dohrni, Scaphella, 251, pl. 13] dolabrata, Pyramidella, 289, pl. 4q dolabriformis, Spisula, 448, fig. goa doliarium, Calliostoma, 115, 116, pl. 34q; fig. 33h Dolium, 199 domingensis, Barbatia, 343, pl. 27u dominguensis, Cardita, 378, 380 dominicensis, Spondylus, 370 Donax, 437 californica, 438, pl. 31p denticulata, 438, pl. 30p fossor, 437 gouldi, 438, pl. 31q roemeri, 437, pl. 30q striata, 438 tumida, 438 variabilis, 437, pl. 30r donilla, Odostomia, 290, fig. 63r Doridae, 299 Doriopsis, 303 dorsalis, Xylophaga, 463 Dorytewthis plei, 483 Dosina, 404 Dosinia, 417 discus, 417, fig. 81¢ elegans, 417 Dosinidia, 417 draconis, Polinices, 187, 189, fig. 43a Dreissenidae, 382 Drupa nodulosa, 211, pl. 25v dubia, Scaphella, 251 dubiosa, Cyathodonta, 472 dupetit-thouarsi, Fusinus, pl. 24zz, not in text duplicatus, Polinices, 186, 191, pls. sk, 22h dysoni, Diodora, 97, pl. 17n ebenina, Crassispira, 268, fig. 57} eboreum, Dentalium, 331, fig. 69e eburneola, Marginella, 254 eburneum, Cerithium, 154, pl. 19q eburneum, Epitonium, 164 Scientific Names echinata, Pseudochama, 393 echinatus, Spondylus, 370 Echininus nodulosus, 134, 135, pl. 19h Echinochama, 391, 394 arcinella, 394, pl. 37h californica, 394, pl. 37e cornuta, 394, pl. 37g edulis, Mytilus, 354, pl. 35m edulis, Ostrea, 373 edulis diegensis, Mytilus, 354 egmontianum, Trachycardium, 397, pl. _ 39-0 Egregia, 105 elatum, Laevicardium, 400 elegans, Ancistrosyrinx, 268 elegans, Dosinia, 417 elegans, Fossarus, 176, pl. 25¢ elegans, Haminoea, 279 Elephantanellum, 148 elephantinum, Dentalium, 55 Ellipetylus, 139 elongata, Cavolina, 298 elucens, Tellina, 423 emarginata, Thais, 216, fig. 48a Emarginula phrixodes, 94, pl. 17-0 emersont, Cerithiopsis, 157 Engina turbinella, 232, pl. 25w; (249) Ensis, 443 californicus, 443 directus, (35), 443, pl. 30k; fig. 11d megistus, 443 minor, 443 myrae, 443 entale, Dentalium, 329 entale stimpsoni, Dentalium, 328 Entemnotrochus, 92 Entoconchidae, note 160 Entodesma saxicola, 469, pl. 29m Eontia, 346 epae, Sthenorytis, 161 Epilucina, 390 Episiphon, 331 Epitonium, 163 angulatum, 164, 165, pl. 22b clathrum, 165 commune, 164 contorquata, 163 eburneum, 164 foliaceicostum, 164 humphreysi, 164, pl. 22d indianorum, 165 krebsi, 163, fig. goe lamellosum, 165, pl. 22a lineatum, 165 muricata, 165 occidentale, 163 pretiosula, 165 reynoldsi, 165 rupicolum, 165, pl. 22e spina-rosae, 165 Swifti, 163 tollini, 164 equalis, Rossia, 480 equestris, Cheila, 165, pl. 21p equestris, Ostrea, 373, pl. 28c Erato, 176 25 columbella, 176 maugeriae, 176, pl. 22w vitillina, 176, pl. 20-0 Eratoidae, 176 Eratoidea, 254 erectus, Petaloconchus, 143 erinaceoides rhyssus, Murex, 206 Erosaria, 180 erosum, Tachyrhynchus, 140, 141, pl. 21-1 Ervilia, 452 concentrica, 452 rostratula, 452 Erycina fernandina, 397 Erycinidae, 394 eschrichti, Bittium, 155, 156 estephomenos, Melongena, 234 etterae, Eupleura, 219 Eubranchus, 309 exiguus, 309, pl. 15¢ pallidus, 310, pl. 15h eucosmia, Neptunea, 230, fig. 51d eucosmius, Fusinus, 243, pl. 11¢; fig. 22k Eucrassatella, 376 floridana, 377 gibbesi, 377 speciosa, 377, pl. 30z eucymata, Callista, 415, pl. 39-i Eudolium crosseanum, 199, pl. 23g euglyptum, Calliostoma, 112, pl. 17w Eulamellibranchia, 332 Eulimidae, 160 Eulithidium, 127 rubrilineatum, 127 variegata, 128 Funaticina oldroydi, 188, fig. 43e Eupleura, 219 caudata, 219, fig. 47b etterae, 219 stimpsoni, 209, fig. 47a sulcidentata, 219, fig. 47¢ Euribia, 299 Eurytellina, 427 Euvola, 361, 362 Evalea, 290 Evalina, 290 exacuta, Cleodora, 295 exacuta, Clio, 295 exanthema, Cypraea, 180 exasperatus, Aequipecten, 367 excavata, Crepidula, 172 excavata, Tegula, 119 exigua, Janthina, 160, pl. 4-1 exigua, Nucula, 335 exiguus, Eubranchus, 309, pl. 15¢ exogyra, Pseudochama, 393 exoleta, Turritella, 141, pl. 21h expansa, Ostrea, 374 exustus, Brachidontes, 352, pl. 35} faba, Crenella, 350, fig. 75a falcata, Botula, 356, pl. 29k falcata, Clio, 295 falcata, Spisula, 447 farella, Odostomia, 290, fig. 63-1 fargoi, Vermicularia, 145, pl. 21b 526 Fartulum, 149 fasciata, Tegula, 118, pl. 17p fascicularis, Fissurella, 101, pl. 17g Fasciolaria, 242 branhamae, 242 distans, 242 gigantea, see Pleuroploca, 242 hunteria, 242, pl. 13c princeps, see Pleuroploca, 242 tulipa, 242, pl. 13b Fasciolariidae, 240 fastigiata, Calyptraea, 169, pl. 20-1 fausta, Arcopagia, 428, pl. 40} fausta, Tellina, 428 Favartia, 204 feldmanni, Yerebra, 265 femorale, Cymatium, 195, pl. 5d fenestrata, Acmaea, 102, pl. 18t fenestrata, Liotia, 122, pl. 18u fergusoni, Mitra, 248 Ferminoscala, 163 ferruginea, Pseudochama, 393 festivus, Murex, 206, pl. 24-1 fetella, Odostomia, 290, fig. 63s Ficidae, 200 Ficus, 200, 236 carolae, 200 communis, 200, pl. 9-1 papyratia, 200 reticulata, 200 filiata, Codakia, 391 Filibranchia, 332, 341 filosa, Mitromorpha, 273, fig. 57-1 filosa, Pandora, 470 filosus, Phacoides, 388, 389, pl. 38}; fig. 78a filum, Dentalium, 331 fimbriatula, Bankia, 467, fig. 95f firma, Chama, 393 fischeriana, Verticordia, 474 fissa, Mopalia, 315 Fissidentalium, 330 Fissurella, 100 angusta, 100 barbadensis, 100, pl. 17f crucifera, 101 fascicularis, 101, pl. 17g nodosa, 100, pl. 17d rosea, 100, pl. 17e volcano, 100, pl. 18c Fissurellidae, 94 Fistulana Bruguiére, 459 flabella, Venericardia, 380 Flabellinidae, 309 flammea, Cassis, 193 flammea, Terebra, 265 flavomaculata, Cadlina, 302 flexa, Acanthopleura, 314 flexa, Nuttallina, 314 flexuosa, Rangia, 450, fig. 91 flexuosa, Strigilla, 429 floralia, Olivella, 247 florida, Mitra, 248, pl. 13-1 florida, Scaphella, 251 floridana, Cardita, 378; pl. 30a Index floridana, Distorsio, 197 floridana, Eucrassatella, 377 floridana, Lucina, 387, pls. 30aa, 38-i floridana, Lyonsia, 468 floridana, Muricopsis, 211 floridana, Neritina, 130 floridana, Onchidella, 274 floridana, Pseudocyrena, 381, pl. 30y floridana, Terebra, 265 floridana, Tivela, 412 floridanum, Caecum, 146, fig. 37a floridanum, Cerithium, 153, pl. 19n floridanus burryae, Conus, 261 floridanus, Conus, 261, pl. 14d floridanus, Cryptoconchus, 317, fig. 67b floridanus floridensis, Conus, 261, pl. 14e floridanus, Ischnochiton, 320 floridense, Dentalium, 330 floridensis, Aplysia, 285 floridensis, Crassostrea, 375 florifer, Murex, 203, pl. roe fluctifraga, Chione, 408, pl. 31k folaceicostum, Epitonium, 164 foliata, Pterorytis, 218, pl. 24h foliatum, Ceratostoma, 219 foliatum, Purpura, 219 folium, Ostrea, 373 folly ensis, Urosalpinx, 212 fornicata, Crepidula, 170, 171, 172, pl. 21m fornicata, Volsella, 352, pl. 29-0 Forreria, 200 belcheri, 200, pl. 24-1 cerrosensis catalinensis, 201, 208, fig. 44c, d cerrosensis cerrosensis, 200, 208, fig. 44a, b pinnata, 201, 208 forsteri, Glaucus, 309 fossa, Nuculana, 337 Fossaridae, 176 Fossarus elegans, 176, pl. 25¢ fossatus, Nassarius, 240, pl. 20s fossor, Donax, 437 fragile, Periploma, 473 fragilis, Janthina, 160 fragilis, Mactra, 445, pl. 32s; fig. 89 fragilis, Sphenia, 455° Fraginae, 398 frenulata, Rimula, 95, fig. 30d fretensis, Gemma, 419 frisbeyae, Conus, 264 frondosus, Dendronotus, 307, pl. 15¢ frons, Ostrea, 373, pl. 28d fucanum, Clinocardium, 403 Fugleria, 343 fulgens, Haliotis, 93, pl. 2b Fulgur, 235 fulgurans, Nerita, 128, 129, pl. 4e Fulguropsis, 236 fulminata, Pitar, 414, pl. 39d fulva, Dendrodoris, 303 fulvescens, Murex, 203, pl. rob funebralis, Tegula, 104, 119 fungoides, Acmaea, 107 fusca, Botula, 356 fusca, Pyramidella, 288, fig. 62e fusco-purpureus, Aequipecten, 367 Fusinus, 241 barbarensis, 244, pl. 24z couel, 268, pl. 13d depetitthouarsi, pl. 24zz, not in text eucosmius, 243, pl. r1c; fig. 22k harfordi, 243, fig. 54a kobelti, 243, fig. 54b timessus, 243, pl. 11g Fusitriton, 194 gabbi, Glyphostoma, 272 gabbi, Zirfaea, 462 Gadila, 327, 328 galea, Tonna, 199, pl. 23f galeata, Puncturella, 96, fig. 30c Galeodes, 234 gallicana, Hiatella, 453 gallina, Tegula, 119, pl. 18v gallus, Strombus, 175, pl. 5e gardineri, Pleurobranchus, 287 Gari californica, 441, pl. 29n Gastrana, 433, fig. 88e Gastrochaena, 459 Gastropteridae, 283 Gastropteron, 283 cinereum, 285 meckeli, 284 pacificum, 285 rubrum, 17, 283, fig. 60e gausapata, Nitidella, 223 Gaza, 118 superba, 118, pl. 3b watsoni, 118, fig. 32a Gemma, 418 fretensis, 419 gemma, 418, pl. 38k; fig. 84 manhattensis, 419 | purpurea, 419 \ gemma, Arene, 122, pl. 17q gemma, Cardiomya, 476 gemma, Gemma, 418, pl. 38k; fig. 84 gemma, Murex, 206, pl. 24e Gemminae, 418 Gemmula periscelida, 267, fig. 57¢ gemmulatum, Calliostoma, 115, fig. 33d generosa, Panope, 454 Genota viabrunnea, 271, fig. 57g georgiana, Scaphella, 251 gibba, Melanella, pl. 21v, not in text gibberosa, Astraea, 125, fig. 35 Gibberula, 257 Gibberulina, 258, 259 amuanta, 260 hadria, 260 lacrimula, 260 ovuliformis, 258, 259, fig. 56-0 pyriformis, 260, fig. 56n gibbesi, Eucrassatella, 377 gibbosa, Cavolina, 296, fig. 64w gibbosa, Odostomia, 288, fig. 62k gibbosa, Plicatula, 361, pl. 35¢e gibbosum, Cyphoma, 183, pl. 8, pl. qr gibbus, Aequipecten, 368, pl. 33) gibbus nucleus, Aequipecten, 368, pl. 34h gibbus, Tagelus, 440 gigantea, Fasciolaria (see Pleuroploca), 242 gigantea, Lottia, 101, pl. 18} gigantea, Pleuroploca, 242, pl. 13a giganteus, Dendronotus, 307 giganteus, Hinnites, 369 giganteus, Saxidomus, 417 gigas, Crassostrea, 374, 375, pl. 29g gigas, Strombus, 174, pl. 23a glabra, Haminoea, 279 glaciale, Buccinum, 226, pl. 24t glacialis, Cuspidaria, 475, fig. 97b glandula, Crenella, 350, pl. 28); fig. 75b, c Glans, 378 glauca, Crepidula, 171 Glaucidae, 309 glaucum, Phalium, 192 Glaucus, 309 atlanticus, 309 forsteri, 309 marina, 309 radiata, 309 Glicymeris, see Glycymeris, 348 globosa, Diaphana, 277 globosa, Janthina, 160, pl. 4k globosa, Panope, 454 globosa, Trivia, 178 gloriosum, Calliostoma, 116, fig. 33a Glossaulax, 187 Glossodoris, 303 californiensis, 303 macfarlandi, 303 porterae, 303, pl. 16-1 universitatis, 303 Glycimeris, see Glycymeris, 348 Glycymeridae, 341, 346, 348 Glycymeris, 348 americana, 349 decussata, 348, pl. 27h lineata, 348 pectinata, 348, pl. 27-i pennacea, 348 spectralis, 348 subobsoleta, 349, pl. 31e undata, 348, 349, pl. 27g Glyphostoma gabbi, 272 glyptus, Aequipecten, 366, pl. 33a gnidia, Chione, pl. 31d, not in text Gobraeus, 442 goliath, Strombus, 6 golischi, Mysella, 396 goniogyrus, Teinostoma, 140 Gonyaulax catanella, 39 gouldi, Bankia, 466, figs. 16, 95d gouldi, Cylichna, 282 gouldi, Donax, 438, pl. 31q gouldi, Nitidella, 222, pl. 2om gouldi, Spiratella, 292 gouldi, Thyasira, 384 Gouldia cerina, 415 Scientific Names gouldiana, Bulla, 278 gouldiana, Pandora, 470, fig. g6c gracile, Cymatium, 195, 196, pl. 25n gracilis, Cardita, 378 gracilis, Melanella, pl. 21u, not in text gracillima, Ocenebra, 217, pl. 24m grandis, Anadara, 344 grandis, Placopecten, 366 grandis, Triopha, 304, pl. 16b granti, Pseudochama, 393 Granula, 258 granularis, Bursa, 198, pl. 25-0 granulata, Acanthopleura, 326 granulata, Architectonica, 143 granulata, Cuspidaria, 476 granulata, Pandora, 471 granulata, Poromya, 475, pl. 30s granulatum, Phalium, 192, pl. 9e granulatus, Conus, 264, pl. 14-1 granulosa, Diplodonta, 383 Graptacme, 331 grata, Protothaca, 411 greeni, Cerithiopsis, 157, pl. 19v grippi, Caecum, 147 grippi, Cerithiopsis, 158 groenlandica, Littorina, 133 groenlandica, Lunatia, 189, 190, pl. 22k groenlandica, Margarites, 107 groenlandicus, Margarites, 108, fig. 31d groenlandicus, Serripes, 401, pl. 32d grus, Chione, 408, pl. 32-1 Gryphaea, 374 guadeloupensis, Astraea, 124 guttatum, Prunum, 256, pl. 11m Gutturnium, 196 Gymnobela blakeana, 273, fig. 57h Gymnosomata, 292, 299 Gyroscala, 165 hadria, Gibberulina, 260 haemastoma, Thais, 213 haemastoma floridana, Thais, 213, 214, pl. 25a haemastoma haysae, Thais, 213 haematita, Marginella, 254, fig. 56a Haliotidae, 92 Haliotis, 92, 372 assimilis, 93, pl. 2d aulaea, 93 bonita, 92 californiensis, 92 corrugata, 93, pl. 2c cracherodi, 92, pl. 2f diegoensis, 93 fulgens, 93, pl. 2b holzneri, 92 imperforata, 92 kamtschatkana, 94, pl. 2e lusus, 92 pourtalesi, 94 TeEVEA, 93 rufescens, 92, pl. 2a smithsoni, 93 ay SOrensent, 93 splendens, 93 splendidula, 92 turveri, 93 walallensis, 93 Haliris, 474 Haloconcha reflexa, 131 Halopsyche, 299 hamata, Nuculana, 339, fig. 26d hamatus, Brachidontes, 353 hamatus, Mytilus, 353 Haminoea, 279 antillarum, 279 cymbiformis, 279 elegans, 279 glabra, 279 olgae, 279 solitaria, 279, pl. 26s succinea, 279 vesicula, 279 virescens, 279 haudignobilis, Pinna, 360 harfordi, Fusinus, 243, fig. 54a harpa, Volutopsius, 226, pl. 24p hartwegi, Lepidochitona, 314 harveyi, Architeuthis, 483, fig. 99c hastata, Terebra, 266, pl. 26h hastatus hastatus, Chlamys, 364, pl. 34] hastatus hericius, Chlamys, 364, pl. 34k heathi, Discodoris, 300, pl. 161 hegewischi californica, Cerithidea, 152 belblingi, Barbatia, 343 helga, Odostomia, 290, fig. 63n helicina, Spiratella, 292, fig. 64a helicoidea, Vitrinella, 138 hemiptera, Lolliguncula, 482 hemphilli, Caecum, 150 hemphilli, Lima, 371, pl. 29¢ hemphilli, Spisula, 448, fig. gob hendersoni, Mitra, 249, pl. 26c hendersoni, Odostomia, 288, fig. 62g hendersoni, Sthenorytis, 161 heptagonum, Caecum, 148, fig. 37k Here, 385 heros, Lunatia, 189, fig. 22a Herse, see Cuvierina, 298 cancellata, 299 columnella, 299, fig. 64m Oryza, 299 urceolaris, 299 Hespererato, 176 Heterodonax, 441 bimaculata, 441, pl. 301 pacifica, 441 hexagona, Muricopsis, 209, pl. zsh Hexaplex, 202 hians, Argonauta, 485, fig. 99e, f hians, Lima, 370 hians, Rocellaria, 459 Hiatella, 452 arctica, 452, fig. 92a gallicana, 453 pholadis, 453 528 TULOSA, 453 striata, 453, fig. 92b hiatus, Papyridea, 398 hidalgoi, Murex, 203, fig. 45a hiemalis, Diaphana, 277 hindsi, Chlamys, 365, pl. 34-1 hindsi, Coralliophila, 220 hindsi, Mopalia, 315, 316 hindsi, Nuculana, 339 Hinia, 239 Hinnites, 361, 368 giganteus, 369 multirugosus, 369, pl. 29a Hipponicidae, 165 Hipponix, 166 antiquatus, 166, 168, pl 21t barbatus, 167 benthophila, 166 cranoides, 166 serratus, 166 subrufus subrufus, 166 subrufus tumens, 166 holograpta, Sigatica, 187 holzneri, Haliotis, 92 Homalopoma, 125 albida, 125 bacula, 126 carpenteri, 126, pl. 181 linnei, 126 lurida, 126 hongkongensis, Octopus, 488, fig. roof Hopkinsia rosacea, 307, pl. 16a Hormomya, 352 horridus, Strombus, 174 hotessieriana, Opalia, 162, pl. 22g hotessieriana, Tegula, 119 Humilaria kennerleyi, 410 hummi, Polycera, 306 humphreysi, Epitonium, 164, pl. 22d hunteria, Fasciolaria, 242, pl. 13¢ Hyalaea, 294, 296 affinis, 296 angulata, 296 coniformis, 294 limbata, 296 Hyalina, 258 avena, 258, pl. 11p; fig. 561 avenacea, 259, fig. 56 avenella, 259 beyerleana, 258 californica, 259 succinea, 259 torticula, 259, fig. 56-1 veliei, 258 hyalina, Lyonsia, 468, pl. 28u Hyalocylis striata, 294, fig. 64q Hydatina, 276 physis, 276 vesicaria, 276, pl. 13q Hydatinidae, 276 hyotis, Pycnodonta, 374, pl. 38a Hysteroconcha, 415 idae, Mitra, 249, pl. 2op idae, Tellina, 422, figs. 87a, 28h Index Idioraphe, 140 illecebrosus, Illex, 483 Illex illecebrosus, 483, fig. g9b Ilyanassa, 240 imbricata, Astraea, 124 imbricatus, Chlamys, 364, pl. 34f imbricatus, Thais, 215 imitans, Cavolina, 298 immaculatus, Polinices, 186 imperforata, Haliotis, 92 imperforatus, Polinices, 187 impressa, Odostomia, 288, fig. 621 inaequalis, Astraea, 125 inaequivalvis, Periploma, 473 inclusus, Amphithalamus, 136 incongrua, Anadara, 346 incongrua, Macoma, 434, fig. 88b incurvatus, Capulus, 168 indentata, Macoma, 432 indianorum, Epitonium, 165 indusi, Tegula, 118 inequale, Periploma, 473, pl. 28x inermis, Cavolina, 298 inflata, Lima, 370 inflata, Spiratella, 293, fig. 64h inflatula, Macoma, 433 inflatum, Phalium (Semicassis), 193 inflexa, Cavolina, 298, fig. 64r inflexa, Neosimnia, 183, pl. 7h infundibulum, Latirus, 241, pl. 11a Inodrillara, 271 Inodrillia aepynota, 271, fig. 57b inornata, Microgaza, 111 inquinata, Macoma, 433 insculpta, Opalia, 162 insculptus, Nassarius, 237, fig. 53f insessa, Acmaea, 105, pl. 18z insignis, Trichotropis, 168, pl. 24c inspinata, Melongena, 234 instabilis, Acmaea, 105, pl. 18zz intapurpurea, Chione, 407, pl. 39g intastriata, Apolymetis, 434, pl. 32y interfossa, Ocenebra, 216, fig. 49a interfossum, Bittium, 156 intermedia, Cavolina, 298 interpurpurea, Chione, 407 interrupta, Tellina, 422, pl. 4o-l interrupta, Turbonilla, 288, fig. 62b intorta, Olivella, 247 intortus, Capulus, 168 intricata, Bailya, 231, pl. 25t Tolaea, 288, 290 Iphigenia brasiliensis, 439, pl. 32u iris, Tellina, 427 irradians, Aequipecten, 367, pl. 32-1 irradians amplicostatus, Aequipecten, 368, fig. 26f irradians concentricus, Aequipecten, 368 irradians irradians, Aequipecten, 368 irregularis, Petaloconchus, 143, pl. 21d irrorata, Littorina, 132, pl. 19¢ irus, Gastrana, 433 Irus lamellifera, 412, pl. 31r Ischadium, 353 Ischnochiton, 313, 320 acrior, 321! albus, 313, 322 californiensis, 323 clathratus, 323 conspicuus, 321 cooper, 323 floridanus, 320 magdalenensis, 321 mertensi, 322 palmulatus, 323 papillosus, 320 purpurascens, 320 regularis, 322 Tuber, 313, 322 Ischnochitoniidae, 319 islandica, Amauropsis, 187, pl. 22r islandica, Arctica, 381, pl. 32f islandicus, Chlamys, 365, pl. 27-1 isocardia, Trachycardium, 397 Isognomon, 358 alata, 358, pl. 35b bicolor, 358 chemnitziana, 358 listeri, 358 radiata, 358, pl. 35a Isognomonidae, 358 Ivara, 290 Ividella, 290 jacobaeus, Pecten, 11 jamaicensis, Acmaea, 106, pl. 17¢ jamaicensis, Barbatia, 343 jamaicensis, Lucina, 388 jamaicensis, Phacoides, 388 Janacus, 172 janeirensis, Calloplax, 319, fig. 67¢ Janthina, 160, 309 bifida, 160 exigua, 160, pl. 4-1 fragilis, 160 globosa, 160, pl. 4k janthina, 160, pl. 4j janthina, Janthina, 160, pl. 4] Janthinidae, 160 japonica, Mya, 455 jaspidea, Marginella, 254 jaspidea, Olivella, 246, pl. 11-1 jaspideus, Conus, 262, pls. 14n, 22x jeffreysi, Cuspidaria, 475 jewetti, Persicula, 258 johnstoneae, Scaphella, 250 joubini, Octopus, 488, fig. rood jujubinum, Calliostoma, 113, pl. 3p juliae, Conus, 261, pl. r4b Jumala, 227 crebricostata, 227, fig. s1b kennicotti, 227, fig. 51g junonia, Scaphella, 250, 251, pl. 13f kamtschatkana, Haliotis, 94, pl. 2e Katharina tunicata, 316, fig. 66b keepiana, Lepidochitona, 314 Kelletia kelletia, 231, pl. 24w kelletia, Kelletia, 231, pl. 24w Kellia laperousi, 394 Kelliidae, 394 kelseyi, Cingula, 135 kelseyi, Milneria, 380, fig. 76 kelseyi, Rissoina, 136 kelseyi, Turbonilla, 290, fig. 63b kennerleyi, Humilaria, 410 Kennerlia, 470 kennicotti, Jumala, 227, fig. 51g keraudreni, Oxygyrus, 184 kieneri, Busycon, 236 knorri, Vermicularia, 145, pl. 21a kobelti, Fusinus, 243, fig. 54b krebsi, Architectonica, 143, pl. 4-0, 21y krebsi, Epitonium, 163, fig. 40e Krebsia, 168 kurriana, Cyrtodaria, 453 Kurtziella limonitella, 272, fig. 57a kyskensis, Cingula, 135 labiata, Cavolina, 298 labiatum, Prunum, 256, pl. 11-1 Labiosa, 449 campechensis, 449 canaliculata, 449 lineata, 449 plicatella, 449, pl. 32q labiosum, Cymatium, 196, pl. 25m labradorensis, Aporrhais, 173 laciniata, Protothaca, 410 lacrimula, Gibberulina, 260 lacteolum, Tachyrhynchus, 141 lacteus, Polinices, 185, 187, pl. 22-i Lacuna, 130 carinata, 131, fig. 36a divaricata, 131 porrecta, 131 solidula, 131 striata, 131 unifasciata, 131, fig. 36b variegata, 131 vincta, 130, 131, pl. 22p; fig. 36c-e lacunatus, Amphithalamus, 136 lacunella, Solariella, 110, fig. 32b, c. Lacunidae, 130 Laevicardium, 399 elatum, 400 laevigatum, 399, pl. 39k mortoni, 400, pl. 39-1 pictum, 400 serratum, 400 substriatum, 400 sybariticum, 400 laevigata, Rissoina, 137 laevigata, Tellina, 422, pl. 40k laevigata, Velutina, 175, pl. 22n laevigatum, Laevicardium, 399, pl. 39k laevigatus, Chiton, 324 laevigatus, Musculus, 355, pl. 28f laevis, Cadlina, 302 Laila cockerelli, 304, pl. 16) lamarcki, Carinaria, 185, fig. 42 Lamellaria, 175 diegoensis, 175, fig. 43d rhombica, 175 Lamellariidae, 175 Scientific Names Lamellibranchia, 332 lamellifera, Irus, 412, pl. 31r lamellosa, Solariella, 110, pl. 17x lamellosa, Thais, 215, 216, figs. 48e-h lamellosum, Epitonium, 165, pl. 22a laminata, Turbonilla, 290, fig. 63-1 Lampusia, 195 lanceolata, Clio, 295 lanceolata, Colubraria, 232, pl. 25x laperousi, Crassostrea, 375 laperousi, Kellia, 394 lapicida, Petricola, 419 lapilloides, Acanthina, 211 lapillus, Nucella, 215 lapillus, Thais, 214, pl. 25g laqueatum, Dentalium, 328 Larkinia, 344 Lasaea, 353, 395 cistula, 353, 395 subviridis, 353, 395 lasius, Trophonopsis, 208 Laskeya, 157 lateralis, Musculus, 355, fig. 75¢ Latiaxis, 220 latilirata, Chione, 409, pl. 39c Latirus, 241 brevicaudatus, 241, pl. 11f infundibulum, 241, pl. 11a megintyi, 241, pl. 11b laurenti, Pecten, 362, pl. 33f lavalleana, Persicula, 258 laxa, Odostomia, 290, fig. 63t leachi plei, Bursatella, 286 leanum, Periploma, 474, pl. 28v Leda, see Nuculana, 336 Ledella, 337 Leiomya, 476 Lepeta caeca, 107, pl. 17] Lepetidae, 107 Lepidochitona, 313 dentiens, 314 hartwegi, 314 keepiana, 314 Lepidopleuridae, 312 Lepidopleuroides, 322 Lepidopleurus cancellatus, 312 Lepidozona, 322 Leptegouana, 256 Leptonidae, 394 Leptothyra, 125 leremum, Teinostoma, 140 lermondi, Caecum, 150 lesueuri, Spiratella, 293, fig. 64b leucocyma, Lucina, 387, fig. 78d, e leucocyma, Monilispira, 271, fig. 57d leucophaeta, Congeria, 382 leucopleura, Acmaea, 106, 310, pl. 17b leucosphaera, Trivia, 178 Leucozonia, 240 cingulifera, 241 nassa, 240, pl. 11d ocellata, 241, pl. rre Levia, 149 lewisi, Lunatia, 187, 188, 189, pl. 24n licalum, Caecum, 147 322) lienosa, Anadara, 345 lienosa floridana, Anadara, 344, pl. 27-0 ligatum, Calliostoma, 116, fig. 33g lignosa, Mopalia, 315 ligulata, Tegula, 120, pl. 18h Lima, 370 antillensis, 370 caribaea, 370 dehiscens, 371 hemphilli, 371, pl. z9c hians, 370 inflata, 370 lima, 370, pl. 35¢ multicostata, 370 orientalis, 371 pellucida, 370 scabra, 370, pl. 35f, 0 squamosa, 370 tenera, 371 terica, 370 lima, Lima, 370, pl. 35g lima, Philine, 283, fig. sof lima, Thais, 216, fig. 48d limacella, Ostrea, 373 Limacina, 292 balea, 292 scaphoidea, 293 limatula, Acmaea, 102, pl. 18-0 limatula, Lucapinella, 98, pl. 171 limatula, Terebra, 266 limatula, Yoldia, (44), 340, fig. 71b limatula gardneri, Yoldia, 340 limatulum, Prunum, 257, fig. 56f limbata, Cavolina, 296 limbata, Hyalaea, 296 Limea bronniana, 371 Limidae, 370 limonitella, Kurtziella, 272, fig. 57a Limopsidae, 341, 346 Limopsis, 346 antillensis, 347 cristata, 347 diegensis, 347, fig. 73 minuta, 347 sulcata, 347, pl. 27f limula, Macoma, 432 lineata, Glycymeris, 348 lineata, Labiosa, 449 lineata, Tellina, 427, pl. 4oh lineata, Tonicella, 312, 313 lineatum, Epitonium, 165 lineatus, Planaxis, 150 lineolaris, Aequipecten, 367 lineolata, Philine, 283 lineolata, Siphonaria, 310 Linga, 385 lingulata, Crepipatella, 170, pl. zok linnei, Homalopoma, 126 lintea, Quadrans, 430, fig. 86g Lioberus castaneus, 356 lioica, Abra, 437, pl. 30w Liophora, 409 Liotia, 121 bairdi, 121, pl. 17u cookeana, 122 530 fenestrata, 122, pl. 18u lirata, Chrysodomus, 230 lirata, Neptunea, 230 lirulatus, Margarites, 108, fig. 31¢ Lischkeia, 109 bairdi, 109, pl. 3c cidaris, 109, fig. 31h Ottol, 110 regalis, 110 listeri, Antigona, 404, pl. 32m listeri, Diodora, 96, pl. 17-1 listeri, Isognomon, 358 literatum, Cerithium, 154, pl. 19-1 Lithophaga, 356 antillarum, 357, 382, pl. 28k aristata, 357, pl. 29] bisulcata, 357, pl. 28n nigra, 356, pl. 28m plumula, 357 plumula kelseyi, 357, pl. 29-1 Lithopoma, 124 Litiopa, 131, 156 bombix, 157 bombyx, 157 melanostoma, 156, pl. 21k litterata, Oliva, 245 littorea, Littorina, 132, 133, pl. 19b Littorina, 130, 132, 150 angulifera, 132, 133, pl. 19a groenlandica, 133 irrorata, 132, pl. 19c¢ littorea, 132, 133, pl. r9b meleagris, pl. 19}, not in text mespillum, 133, pl. 19k obtusata, 133, pl. rof palliata, 133 planaxis, 134, pl. 20a rudis, 133 saxatilis, 133, pl. 19d scabra, 133 scutulata, 134, pl. 20c sitkana, 134, pl. 2ob ziCzac, 132, pl. 19e lituellus, Spiroglyphus, 144, pl. 20d lituspalmarum, Teinostoma, 139 livida, Natica, 186, 191, pl. 22-0 lividomaculata, Tegula, 118 lividus, Macron, 234, pl. 24x Livona, 116 loebbeckeana, Neosimnia, 183, pl. 7-i Loligo, 480 opalescens, 482 pealei, 480, fig. 99a Lolliguncula, 482 brevipinna, 482 brevis, 482, fig. 99g hemiptera, 482 Lonchaeus, 290 longirostris, Cavolina, 296, fig. 64v longispina, Astraea, 123, pl. 3k, m longleyi, Xenophora, 173 lordi, Psephidia, 411, fig. 82a Lottia gigantea, ror, pl. 18) louisa, Bursa, 198 Lucapina, 98 Index adspersa, 98 cancellata, 98 sowerbii, 98 suffusa, 98 Lucapinella, 98 callomarginata, 99, pl. 18d limatula, 98, pl. 17-1 lucida, Siliqua, 442 Lucina, 385 amiantus, 385, fig. 78c approximata, 387, fig. 78g chrysostoma, 389 crenella, 387 floridana, 387, pls. 30aa, 38-1 leucocyma, 387, fig. 78d, e jamaicensis, 388 multilineata, 386, fig. 78f pensylvanica, 385, pl. 38h sombrerensis, 385, fig. 78b tenuisculpta, 387, fig. 78h Lucinidae, 385 Lucinisca, 388 Lucinoma, 389 Lunarca, 345 Lunatia, 189 groenlandica, 189, 190, pl. 22k heros, 189, fig. 22a lewisi, 187, 188, 189, pl. 24n pallida, 190, fig. 43¢ triseriata, 189, pl. 22m lunata, Mitrella, 223, pl. 25g¢ lunulata, Crassinella, 377, fig. 28k lupinaria, Pitar, 415 Luria, 180 lurida, Homalopoma, 126 lurida, Ocenebra, 217, fig. 49c, d lurida, Ostrea, 374, pl. 2of lusus, Haliotis, 92 lutea, Tellina, 425, fig. 87c, d luteola, Corbula, 459 luteopicta, Aptyxis, 244, fig. 54c lutescens, Terebra, 266 Lyonsia, 468 arenosa, 468 californica, 468 floridana, 468 hyalina, 468, pl. 28u lymneiformis, Daphnella, 273 lyrata, Neptunea, 230, pl. 24q Lyropecten, 361, 366 antillarum, 366, pl. 34¢ nodosus, 366, pl. 33b macerophylla, Chama, 392, pl. 37b; fig. gb macfarlandi, Glossodoris, 303 Machaeroplax, 110 Macoma, 430 balthica, 431, fig. 88g brota, 433, fig. 88a calcarea, 430, fig. 88f carlottensis, 433 constricta, 432 incongrua, 434, fig. 88b indentata, 432 inflatula, 433 inquinata, 433 Irus, 433 limula, 432 mitchelli, not in book nasuta, 432, fig. 88d planiuscula, 433, pl. 30t secta, 432, fig. 88c souleyetiana, 432 tenta, 431 tenuirostris, 432 yoldiformis, 433 Macrocallista, 416 maculata, 416, pls. 1b, 39e nimbosa, 416, pl. 39b Macron lividus, 234, pl. 24x macropterus, Murex, 205 macropus, Octopus, 487, fig. 100e macroschisma, Pododesmus, 372, pl. 294 Mactra, 445 californica, 445, fig. god fragilis, 445, pl. 32s; fig. 89 nasuta, 446 mactracea, Crassinella, 377, pl. 30b Mactridae, key to genera, 445 maculata, Macrocallista, 416, pl. 39e maculata, Triopha, 304, pl. 16f maculatum, Sinum, 190 maculosa, Crepidula, 171 maculosa, Tonna, 199, pl. od madagascariensis, Cassis, 193, pl. 23r madagascariensis spinella, Cassis, 194 magdalenensis, Ischnochiton, 321 magellanicus, Placopecten, 366, pls. 33c¢, — 27m Magilidae, 219 magna, Tellina, 427, pl. 40-i magnum, Trachycardium, 397 mainensis, Aporrhais, 173 Malletia, 341 Malletiidae, 334, 341 maltbiana, Trivia, 178, pl. 21z Mancinella, 214 Mangelia morra, 272, fig. 57-1 Mangilia, see Mangelia, 272 manhattensis, Gemma, 419 Mantellum, 371 marcida, Tegula, 120, pl. 18y Margarites, 107, 126 cinereus, 107 costalis, 107, 110, pl. 17t groenlandica, 107 groenlandicus, 108, fig. 31d lirulatus, 108, fig. 31¢€ obsoletus, 108 parcipictus, 108 pupillus, 109, fig. 31¢ succinctus, 109, fig. 31a umbilicalis, 108 Margaritifera, 359 marginata, Cadlina, 302 Marginella, 176, 254 aureocincta, 254, fig. 56b borealis, 257 denticulata, 254, fig. 56c ee eburneola, 254 haematita, 254, fig. 56a jaspidea, 254 philtata, 254 mariana, Turritella, 142, pl. zoh marina, Glaucus, 309 marmoratus, Chiton, 324, 325 marmorea, Tonicella, 312, 313, 322 Martesia, 464 cuneiformis, 465 smithi, 465 striata, 464, pl. 32w martiniana, Melongena, 234 martinianum, Cymatium, 195, 196, pl. 9-1 Massyla, 252 Mangeria, 326 maugeriae, Erato, 176, pl. 22w Maxwellia, 206 mayaguezensis, Aequipecten, 367 mayori, Cadulus, 328 mazei, Conus, 264, pl. 14k mazycki, Chione, 407 megintyi, Cyphoma, 184, pls. 8, 4s megintyi, Latirus, 241, pl. 11b meckeli, Gastropteron, 284 media, Siliqua, 443 mediterranea, Carinaria, 185 medium, Trigoniocardia, 398, pl. 39m Megatebennus bimaculatus, 99, pl. 18e Megathura crenulata, 99, pl. 18a megathyris Dall, Dentalium, pl. re, not in text Megayoldia, 340 megistus, Ensis, 443 Meioceras, 150 Melanella, pl. 21, not in text bilineata, pl. 21w gibba, pl. 21r gracilis, pl. 21u melanostoma, Litiopa, 156, pl. 21k meleagris, Littorina, pl. 19}, not in text Melongena, 234 altispira, 234 bispinosa, 234 corona, 234, fig. 52 corona perspinosa, 235 estephomenos, 234 inspinata, 234 martiniana, 234 melongena, 235, pl. 23h minor, 234 subcoronata, 235 melongena, Melongena, 235, pl. 23h Melongenidae, 234 mendicus, Nassarius, 240, fig. 53d Menestho, 288, 290 mera, Tellina, 423, fig. 86c mercatoria, Columbella, 220, pl. 25bb Mercenaria, 406 campechiensis, 406, pl. 32g mercenaria, 8, 41, 382, 406, pl. 32h notata, 406 texana, 406 mercenaria, Mercenaria, 8, 41, 382, 406, pl. 32h Scientific Names Meretricinae, 412 meropsis, Tellina, 426, pl. 30w mertensi, Ischnochiton, 322 Mesodesma arctatum, 451, pl. 32r Mesopleura, 440 mespillum, Littorina, 133, pl. 19k messanensis, Nuculana, 337 messorius, Murex, 202 Metaplysia, 286 mexicana, Bankia, 466 Micranellum, 147 Microcardium, 399 peramabile, 399 tinctum, 399 Microgaza, I11 inornata, 111 rotella, 111, fig. 32d, e Micromelo undata, 276, pl. 26u mildredae, Chlamys, 363, pl. 34¢ Milneria kelseyi, 380, fig. 76 minima, Batillaria, 153, 155, pl. 19s minor, Ensis, 443 minor, Melongena, 234 minuta, Cavolina, 298 minuta, Diaphana, 277, fig. s9b minuta, Diodora, 97 minuta, Limopsis, 347 minuta, Nuculana, 336 minuta, Persicula, 257, 260, fig. 56m minuta, Turtonia, 41 minutus, Rhizorus, 281 mirabilis, Strigilla, 429 Miralda, 290 mitchelli, Amaea, 163, pl. 22f; fig. gob mitchelii, Macoma, not in book Mitra, 248 albocincta, 249 barbadensis, 249, pl. 26d fergusoni, 248 florida, 248, pl. 13-1 hendersoni, 249, pl. 26c idae, 249, pl. 2o0p nodulosa, 248, pl. 26b styria, 248 sulcata, 232, 249, pl. 26a swainsoni antillensis, 248 mitra, Acmaea, ror, pl. 18r Mitrella, 223 lunata, 223, pl. 25g¢ raveneli, 223, pl. 25ee tuberosa, 223 variegata, 223 Mitridae, 248 Mitromorpha, 273 aspera, 273, fig. 57m filosa, 273, fig. 57-1 modesta, Odostomia, 288 modesta, Tellina, 425, pl. 31u modestus, Tenagodus, 145 Modiolaria, 355 Modiolus, 351 modiolus, Volsella, 351, fig. 26} Modulidae, 151 Modulus, 151 carchedonius, 151 531 modulus, 151, pl. 21f; fig. 38 modulus, Modulus, 151, pl. 21f; fig. 38 Moerella, 426 Monilispira, 270 albinodata, 270 albomaculata, 271, pl. 26f leucocyma, 271, fig. 57d Monostiolum, 233 montereyense, Bittium, 156 montereyensis, Archidoris, 299, 301, pl. 16h montereyensis, Cingula, 135 montereyensis, Seila, 158 montereyi, Tegula, 120, 121, pl. 18x moorei, Olivella, 246 Mopalia, 315 acuta, 315 ciliata, 315, 316 fissa, 315 hindsi, 315, 316 lignosa, 315 muscosa, 315 plumosa, 315 wosnessenski, 315 Mopaliidae, 315 Mormula, 290 morra, Mangelia, 272, fig. 57-i morrhuana, Pitar, 414, pl. 32-1; fig. 81e mortoni, Laevicardium, 400, pl. 39-1 Morula, 211 Morum oniscus, 192, pl. 25s mucronata, Cavolina, 298 multangula, Pseudoneptunea, 211, fig. 47f multicostata, Anadara, 344 multicostata, Cardiomya, 476 multicostata, Lima, 370 multicostata, Rissoina, 137 multicostatus, Boreotrophon, 207, 208, fig. 46c multiformis, Brachidontes, 353 multilineata, Lucina, 386, fig. 78f multirugosus, Hinnites, 369, pl. 29a multistriata, Vitrinella, 138, pl. 17r Murex, 201 alba, 205 anniae, 202 arenarius, 204 beaui, 202, pl. 10d bequaerti, 205 brandaris, 12, pl. 10j brevifrons, 203, pl. 10a burryi, 203 cabriti, 201, pl. roh carpenteri, 205, fig. 45¢ cellulosus, 204, fig. 45b citrinus, 202 delicatus, 202 erinaceoides rhyssus, 206 festivus, 206, pl. 24-1 florifer, 203, pl. 10e fulvescens, 203, pl. rob gemma, 206, pl. 24¢ macropterus, 205 MeSSOTIUS, 202 32 petri, 20§ pomum, 202, pl. 10-1 recurvirostris, 202 recurvirostris rubidus, 202 recurvirostris sallasi, 202 rufus, 204 tremperi, 205 trialatus, 205, fig. 45¢ trunculus, 12, 13, pl. 10-i tryoni, 202 Murexiella, 203 Index acutus, 237, fig. 53c ambiguus, 239, pl. 23r; fig. 53a californianus, 239 consensus, 239, fig. 53b cooperi, 240 fossatus, 240, pl. 20s insculptus, 237, fig. 53f mendicus, 240, fig. 53d obsoletus, 240, pl. 23p perpinguis, 239, fig. 53e tegulus, 238, pl. 2on rotundata, 130 sphaera, 130 virginea, 129, pl. 4-i weyssei, 130 nesaeum, Teinostoma, 140 Nesta, 94 Nettastomella rostrata, 464 Neverita, 186 newcombei, Rissoina, 137 niger, Musculus, 355, pl. 28g nigra, Lithophaga, 356, pl. 28m nigricans, Petaloconchus, 143, pl. 21¢e nigrocincta, Triphora, 159, pl. 19y nimbosa, Macrocallista, 416, pl. 39b Muricanthus, 203 trivittatus, 239, pl. 23) muricata, Epitonium, 165 vibex, 237, pl. 23q muricatum, Trachycardium, 397, pl. 39p _ massula, Phacoides, 388 muricatum, Vasum, 245, pl. 23-1 muricatus, Tectarius, 134, pl. 19g Muricidae, 200 Muricidea, 209 muricinum, Cymatium, 196, pl. 25r Lae ae 209 floridana, 211 hexagona, 209, pl. 25h ostrearum, 211, fig. 47g murina, Diodora, 98 mus, Conus, 262, pl. 14-0 mus, Cypraea, 181, pl. 6e muscarum, Cerithium, 154, pl. 19m muscosa, Mopalia, 315 muscosus, Aequipecten, 364, 367, pl. 34d, e Musculus, 354 discors, 355, pl. 28e laevigatus, 355, pl. 28f lateralis, 355, fig. 75¢ niger, 355, pl. 28g musica, Voluta, 250, pl. 13g mutica, Olivella, 246, pl. 22v Mya, 454 arenaria, (41), 455, pl. 32x japonica, 455 truncata, 455, pl. 32v Myacea, 454 myalis, Yoldia, 340, pl. 27d Myoforceps, 357 myrae, Ensis, 443 Mysella, 395 golischi, 396 pedroana, 396 planulata, 395 tumida, 397, fig. 80b Mytilimeria nuttalli, 469, pl. 29q Mytilopsis, 382 Mytilus, 351, 354, (338) californianus, 354, pl. 29p edulis, 354, pl. 35m edulis diegensis, 354 hamatus, 353 plicatulus, 352 nana, Astarte, 374 Naranio, 419 Narona cooperi, 253, pl. 24y; fig. 55e nassa, Leucozonia, 240, pl. 11d Nassariidae, 237 Nassarius, 237 nasuta, Corbula, 457 nasuta, Macoma, 432, fig. 88d nasuta, Mactra, 446 nasuta, Rangia, 450 Natica, 191 canrena, 191, pl. 5-1 clausa, 191, fig. 43b livida, 186, 191, pl. 22-0 pusilla, 191, pl. 22] Naticarius, 191 Naticidae, 185 naufragum, Siphonaria, 310 Nautilus pompilius, 48 navalis, Teredo, 467 Navea subglobosa, 464 Navicula ostrearia, 36 nebulosum, Caecum, 149, fig. 37f Neilonella, 341 Nemocardium centifilosum, 399 Neosimnia, 182 acicularis, 182, pl. 7a aequalis, 183 avena, 183, pl. 7g barbarensis, 183 catalinensis, 183 inflexa, 183, pl. 7h loebbeckeana, 183, pl. 7-1 piragua, 182, pl. 7f similis, 183 uniplicata, 182, pl. 7¢ variabilis, 183 Neptunea, 229 bicincta, 230 californica, 230 decemcostata, 229, pl. 23s eucosmia, 230, fig. 51d lirata, 230 lyrata, 230, pl. 24q pribiloffensis, 230, pl. 24r satura, 229 tabulata, 231, fig. 5rf ventricosa, 230, pl. 24s Nerita, 128 fulgurans, 128, 129, pl. 4e peloronta, 128, pl. 4a tessellata, 128, 129, pl. 4f variegata, 128 versicolor, 128, pl. 4b Neritidae, 128 Neritina, 129 floridana, 130 reclivata, 129, pl. 4g nitida, Ringicula, 276 Nitidella, 222 carinata, 222 cribraria, 222 gausapata, 223 gouldi, 222, pl. 2om nitidula, 222, pl. 25dd ocellata, 222, pl. 25hh nitidula, Nitidella, 222, pl. 25dd nitidum, Caecum, 150, We 37e nivea, Olivella, 246, pl. 11h, j nivea, Turbonilla, 288, fig. 62d nix, Trivia, 178, 179 noachina, Puncturella, 95 nobilis, Amiantis, 417 nobilis, Archidoris, 300, 302, pl. 16c nobilis, Architectonica, 142, 143, pl. gm — nobilis, Pseudomalaxis, 139 Nodilittorina tuberculata, 134, 135, pl. 19-1 Nodipecten, 366 nodosa, Fissurella, 100, pl. 17d nodosus, Lyropecten, 366, pl. 33b nodulosa, Drupa, 211, pl. 25v nodulosa, Mitra, 248, pl. 26b nodulosus, Echininus, 134, 135, pl. roh Nodulus, 135 Noetia, 346 ponderosa, 346, pl. 27z; fig. 28a reversa, 346 norrisi, Norrisia, 117, pl. 18m Norrisia norrisi, 117, pl. 18m nota, Odostomia, 290, fig. 63q notabilis, Anadara, 344, pl. 27p Notarchus, see Bursatella, 286 notata, Mercenaria, 406 Notobranchaea, 299 novangliae, Venericardia, 378 Nucella Japillus, 215 nucleus, Planaxis, 150 Nucula, 334 atacellana, 335, fig. 7oe cancellata, 335 crenulata, 335 delphinodonta, (42), 335, fig. 70d exigua, 335 proxima, 334, fig. 70a, b reticulata, 335 tenuis, 335, fig. 70c Nuculana, 336 carpenteri, 337 concentrica, 338 conceptionis, 336 curtulosa, 337 fossa, 337 hamata, 339, fig. 26d hindsi, 339 messanensis, 337 minuta, 336 penderi, 339 pernula, 336 redondoensis, 339 sculpta, 337 taphria, 338, fig. 72a, b tenuisulcata, 336, fig. 71a vaginata, 337 Nuculanidae, 334, 336 Nuculidae, 334 Nudibranchia, 299 nummaria, Crepidula, 172 nuttalli, Clinocardium, 403, pl. 31b nuttalli, Mytilimeria, 469, pl. 29q nuttalli, Phacoides, 388, pl. 31g nuttalli, Pterorytis, 219, pl. 24f nuttalli, Sanguinolaria, 439, pl. 29x nuttalli, Saxidomus, 417, pl. 31- nuttalli, Schizothaerus, 450, pl. 31z Nuttallia, 439 Nuttallina, 314 californica, 314 flexa, 314 scabra, 314 _ obesa, Anachis, 221 - obscura, Solariella, 110, fig. 31f, g obsoletus, Margarites, 108 _ obsoletus, Nassarius, 240, pl. 23p _ obsoletus, Septifer, 354 obtectum, Teinostoma, 140 obtusa, Retusa, 280, 282, fig. 59a obtusata, Littorina, 133, pl. 19f obvelata, Cadlina, 302 occidentale, Caecum, 149, fig. 37] occidentale, Calliostoma, 113 occidentale, Dentalium, 329 occidentale, Epitonium, 163 occidentalis, Aporrhais, 173, pl. 23¢ occidentalis, Arca, 342 occidentalis, Bulla, 277, pl. 26p occidentalis, Solemya, 333 ocellata, Leucozonia, 241, pl. 11e Ocenebra, 209, 216 atropurpurea, 217 circumtexta, 218, fig. 49b citrica, 218 clathrata, 217 gracillima, 217, pl. 24m interfossa, 216, fig. 49a lurida, 217, fig. 49c, d poulsoni, 218, 219, pl. 24k stearnsi, 218 tenuisculpta, 209 Ocinebra, see Ocenebra, 216 _ Octopoda, 484 _ Octopus, 485 americanus, 487 bimaculatus, 488 bimaculoides, 489 Scientific Names briareus, 487, fig. 100c burryi, 487, fig. roob carolinensis, 487 hongkongensis, 488, fig. roof joubini, 488, fig. rood macropus, 487, fig. rooe punctatus, 488 TUgOSUS, 487 vulgaris, 486, fig. rooa Odostomia, 288 aepynota, 290, fig. 63h americana, 290, fig. 63g amianta, 290, fig. 63p bisuturalis, 288, fig. 62h donilla, 250, fig. 63r farella, 250, fig. 63-1 fetella, 290, fig. 63s gibbosa, 288, fig. 62k helga, 290, fig. 63n ' hendersoni, 288, fig. 62g impressa, 288, fig. 62-1 laxa, 290, fig. 63t modesta, 288 nota, 290, fig. 63q pedroana, 290, fig. 63m phanea, 290, fig. 63} seminuda, 288, fig. 62] terricula, 290, fig. 63-0 trifida, 288, fig. 62f willisi, 288, fig. 62a Okeniidae, 306 oldroydi, Eunaticina, 188, fig. 43¢ olgae, Haminoea, 279 Oliva, 245 litterata, 245 reticularis, 245, pl. 12¢ sayana, 245, pl. 12a Olivella, 246 baetica, 247, pl. 20q biplicata, 247, pl. 12-1 floralia, 247 intorta, 247 jaspidea, 246, pl. r1-i moorei, 246 mutica, 246, pl. 22v nivea, 246, pl. rth, j pedroana, 247 porteri, 247 pycna, 247 Olividae, 245 Ommastrephidae, 483 Onchidella, 274, fig. 58 borealis, 275 carpenteri, 274 floridana, 274 Onchidiata, 274 Onchidiidae, 274 Onchidoridae, 305 oniscus, Morum, 192, pl. 25s Onoba, 136 onyx, Crepidula, 171, pl. 2of opalescens, Loligo, 482 Opalia, 162 chacei, 162 crenata, 162 33 crenimarginata, 163 hotessieriana, 162, pl. 22g insculpta, 162 wroblewskii, 162, pl. 20] operculata, Varicorbula, 456 Opisthobranchia, 274 orbella, Diplodonta, 383 orbella, Taras, 383 orbicularis, Codakia, 390, pl. 38d orbiculata, Codakia, 391, pl. 30-1 orcutti, Caecum, 149, fig. 37-1 oregonense, Argobuccinum, 194, pl. 248 oregonense, Caecum, 148 orientalis, Lima, 371 ornata, Verticordia, 474, fig. 97c, d ornatus, Chlamys, 363, pl. 34b ornatus, Triphora, 159 orpheus, Boreotrophkon, 208, fig. 46e oryza, Herse, 299 Ostrea, 373 conchaphila, 374 cristata, 373 edulis, 373 equestris, 373, pl. 28c expansa, 374 folium, 373 frons, 373, pl. 28d limacella, 373 lurida, 374, pl. 2of permollis, 374, pl. 28b rubella, 373 rufoides, 374 spreta, 373 thomtasi, 374 ostrearum, Crassispira, 270, pl. 26n ostrearum, Muricopsis, 211, fig. 47g ostreicola, Anachis, 221 Ostreidae, 373 ottoi, Lischkeia, 110 Oudardia, 425 ovalis, Anadara, 345, pl. 27t ovalis, Psephidia, 411, fig. 82b, not in text ovata, Rocellaria, 460 ovoidea, Pholadidea, 463 ovoidea, Sphenia, 456 Ovulidae, 181 ovuliformis, Gibberulina, 258, 259, fig. 56-0 ovuliformis, Pedicularia, 182, pl. 7¢ oxychone, Vanikoro, 167 Oxygyrus keraudreni, 184 oxytatus, Rhizorus, 280 Pachydesma, 412 Pachypoma, 125 pacifica, Ancula, 307 pacifica, Barnea, 462 pacifica, Heterodonax, 441 pacifica, Rossia, 479 pacifica, Spiratella, 292 pacificum, Gastropteron, 285 pacificus, Boreotrophon, 208, fig. 46f Paedoclione, 299 paleacea, Acmaea, 105 on o-e Paleoconcha, 332, 333 pallasi, Symmetrogephyrus, 317 palliata, Littorina, 133 pallida, Lunatia, 190, fig. 43¢ pallidus, Eubranchus, 310, pl. rsh palmeri, Cingula, 135 palmulatus, Ischnochiton, 323 Pandora, 469 arenosa, 470 bilirata, 471 bushiana, fig. 96a, not in text carolinensis, 470 filosa, 470 gouldiana, 470, fig. 96c granulata, 471 trilineata, 469, fig. g6b Panomya, 453 ampla, 453 arctica, 454 Panope, 454 bitruncata, 454 generosa, 454 globosa, 454 solida, 454 taeniata, 454 paphia, Chione, 409, pl. 39a papillosa, Aeolidia, 308, pl. 15g papillosa, Pleuroploca, 242 papillosus, Ischnochiton, 320 papyraceum, Periploma, 473 papyraceus, Pecten, 362 papyratia, Ficus, 200 papyratia, Pyrula, 200 papyratium, Periploma, 472, pl. 28w papyria, Amygdalum, 353, pl. 28-1 Papyridea, 398 hiatus, 398 semisulcata, 398 soleniformis, 398, pl. 39n Parapholas californica, 464 (and 463) Parastarte triquetra, 419, fig. 85 parcipictus, Margarites, 108 Paroctopus, 488 parva, Bailya, 231 parvicallum, Teinostoma, 140 Parvilucina, 386 patina, Acmaea, 104 Patinopecten, 361 patula, Siliqua, 442, pl. z9y paucilirata, Acanthina, 212 pealei, Loligo, 480, fig. 99a peali, Conus, 263 Pecten, 361 caurinus, 361, pl. 29b diegensis, 169, 361, pl. 33e jacobaeus, 11 laurenti, 362, pl. 33f papyraceus, 362 raveneli, 362, pl. 33g tereinus, 363 tryoni, 367 ziczac, 362, pl. 33d pectinata, Cardiomya, 477 pectinata, Glycymeris, 348, pl. 27-1 pectinata, Siphonaria, 310, fig. 65b Index pectinatus, Phacoides, 388, 388 Pectinidae, 361 peculiaris, Strombus, 174 Pedalion, 358 Pedicularia, 181 californica, 182, pl. 7b, c decussata, 181, pl. 7d ovuliformis, 182, pl. 7¢ Pediculariella, 181 pediculus, Trivia, 177, pl. 21bb pedroana, Cerithiopsis, 158 pedroana, Cyathodonta, 472 pedroana, Mysella, 396 pedroana, Odostomia, 290, fig. 63m pedroana, Terebra, 267 pedroana, Triphora, 159 pedroense, Caecum, 148 pelagica, Scyllaea, 308 Pelecypoda, 332 pellucida, Lima, 370 peloronta, Nerita, 128, pl. 4a pelta, Acmaea, 102, pl. 18n penderi, Nuculana, 339 penicillata, Anachis, 221 penita, Penitella, 463 Penitella, 463 penita, 463 Sagitta, 463 pennacea, Glycymeris, 348 pensylvanica, Lucina, 385, pl. 38h Peracle, 293 bispinosa, 293, fig. 64f clathrata, 293 physoides, 293 reticulata, 293, fig. 64g Peraclidae, 293 Peraclis, see Peracle, 293 peracuta, Architectoniea, 143, pl. 4n, fig. 22 eeemabile Microcardium, 399 peramabilis, Solariella, 111, fig. 31b perdix, Tonna, 199 peregrinus, Boreostrophon, 208 Periploma, 472 discus, 473, figs. 97a, 28-1 fragile, 473 inaequivalvis, 473 inequale, 473, pl. 28x leanum, 474, pl. 28v papyraceum, 473 papyratium, 472, pl. 28w planiusculum, 473, pl. 31x periscelida, Gemmula, 267, fig. 57¢ peristephes, Phalium, 193 permollis, Ostrea, 374, pl. 28b Perna, 358 pernobilis, Sthenorytis, 161, fig. 4oc pernoides, Arca, 343 pernula, Nuculana, 336 peroni, Atlanta, 184, fig. 41 Peronidia, 425 Perotrochus, 91 adansonianus, 92, pl. 3d quoyanus, 92 389, pl. perpinguis, Nassarius, 239, fig. 53e perplana, Venericardia, 380, pl. 28-1 perrugata, Urosalpinx, 211, 212, fig. 47d perryae, Cerodrillia, 270 Persicula, 257 catenata, 257, fig. 56] jewetti, 258 lavelleana, 258 minuta, 257, 260, fig. 56m politula, 258 regularis, 258 subtrigona, 258 persona, Acmaea, 103, pl. 18q perspectivum, Sinum, 190, pl. 22s pertenuis, Retusa, 280 peruviana, Anomia, 372, pl. 29c perversa, Triphora, 159 perversum, Busycon, 236, pl. 23k perviridis, Aplysia, 285 pexata, Anadara, 345 Petaloconchus, 143 erectus, 143 irregularis, 143, pl. 21d nigricans, 143, pl. 21e Petrasma, 333 petri, Murex, 205 Petricola, 419 lapicida, 419 pholadiformis, 420, pl. 322, fig. 94h Petricolaria, 420 Phacoides, 388 acutilineatus, 389 annulatus, 389, fig. 28f centrifuga, 389 filosus, 388, 389, pl. 38}, fig. 78a jamaicensis, 388 nassula, 388 nuttalli, 388, pl. 31g pectinatus, 388, 389, pl. 38g Phalium, 192 abbreviata, 193 centriquadrata, 193 cicatricosum, 193, pl. of glaucum, 192 granulatum, 192, pl. 9e inflatum, 193 peristephes, 193 phanea, Odostomia, 290, fig. 63} Phasianellidae, 126 Philine, 283 lima, 283, fig. sof lineolata, 283 quadrata, 283, fig. 59e sagra, 283 Philinidae, 282 philippiana, Anodontia, 389, pl. 38e philippinarum, Tapes, 410 philtata, Marginella, 254 Pholadidae, 460 Pholadidea ovoidea, 463 pholadiformis, Petricola, 420, pl. 322 pholadis, Hiatella, 453 Pholas campechiensis, 462, pl. 32t phrixodes, Emarginula, 94, pl. 17-0 phrygium, Aequipecten, 367 i el eae Phyctiderma, 383 Phylloda squamifera, 429, fig. 86h Phyllodina, 429 Phyllonotus, 202 Physa, 293 physis, Hydatina, 276 physoides, Peracle, 293 pica, Livona, 106, 117, fig. 34 pictorum, Spondylus, 370, pl. 36a pictum, Laevicardium, 400 pileare, Cymatium, 195 pilosa, Acanthodoris, 305, 306, pl. 156 pilsbryi, Dentalium, 330, fig. 69d pilsbryi, Teinostoma, 140 pilsbryi, Zirfaea, 462 Pinctada radiata, 359, pl. 35¢ Pinna, 259, 320, 359 carnea, 360, pl. 27w haudignobilis, 360 rudis, 360 pinnata, Forreria, 201 Pinnidae, 359 piragua, Neosimnia, 182, pl. 7f Pisania pusio, 233, pl. 13-0 pisiformis, Strigilla, 429 Pitar, 414 albida, 414 cordata, 414, pl. 38n dione, 415, pl. 39f fulminata, 414, pl. 39d lupinaria, 415 morrhuana, 414, pl. 32-1 simpsoni, 414 Pitarenus, 414 Placiphorella velata, 316, fig. 66a Placopecten, 361, 366 grandis, 366 magellanicus, 366, pls. 33c, 27m Plagioctenium, 367 plana, Crepidula, 172 Planaxidae, 150 Planaxis, 150 lineatus, 150 nucleus, 150 planaxis, Littorina, 134, pl. 20a planiuscula, Macoma, 433, pl. 30t planiusculum, Periploma, 473, pl. 31x planulata, Cadlina, 302 planulata, Mysella, 395 planulata, Spisula, 448, fig. goe Platyodon cancellatus, 456 plagosum, Busycon, 237 plebeius, Tagelus, 440, pl. 30d plectrum, Buccinum, 225, fig. 51a plei, Doryteuthis, 483 Pleurobranchidae, 286 Pleurobranchus, 286 atlanticus, 286, fig. 61 gardineri, 287 Pleurolucina, 387 Pleuromeris, 380 Pleuroploca, 242 gigantea, 242, pl. 13a papillosa, 242 princeps, 242 Scientific Names reevel, 242 Pleurotomariidae, 92 plicatella, Labiosa, 449, pl. 32q Plicatula gibbosa, 361, pl. 35¢ plicatula, Volsella, 352 Plicatulidae, 360 plicatulus, Mytilus, 352 pliculosa, Cerithidea, 152, pl. 19t plumosa, Mopalia, 315 plumula, Lithophaga, 357 plumula kelseyi, Lithophaga, 357, pl. 29-1 Plumulella, 467 Pneumoderma, 299 Pneumodermopsis, 299 Pneumonoderma, 299 Pododesmus, 372 cepio, 372 decipiens, 372 macroschisma, 372, pl. 29d rudis, 372, pl. 38b Polinices, 185 alatus, 187 brunneus, 186, pl. 5} draconis, 187, 189, fig. 43a duplicatus, 186, 191, pls. 5k, 22h immaculatus, 186 imperforatus, 187 lacteus, 185, 187, pl. 22-i reclusianus, 187, pl. 20-i uberinus, 185 polita, Tellina, 424 politula, Persicula, 258 politus, Taglus, 441 Pollia, 233 Polycera, 305, 306 atra, 305, pl. 16e hummi, 306 Polyceridae, 304 Polymesoda caroliniana, 381, pl. 30bb polynyma, Spisula, 446, pl. 31w Polyschides, 327 Polystira, 268 albida, 268, pl. 13-1 tellea, 268, pl. 13m viITZO, 268 Polytropa, 214 Pomaulax, 124 pompilius, Nautilus, 48 pomum, Murex, 202, pl. ro-l ponderosa, Bursa, 198 ponderosa, Noetia, 346, pl. 272, fig. 28a porcella, Corbula, 459 porrecta, Lacuna, 131 porterae, Glossodoris, 303, pl. 16-1 porteri, Olivella, 247 Potamididae, 151 poulsoni, Ocenebra, 218, 219, pl. 24k pourtalesi, Haliotis, 94 pourtalesianum, Propeamussium, 369, pl. 27C pretiosula, Epitonium, 165 pretiosum, Dentalium, 330, fig. 6of pretiosum, Epitonium, 6 535 pribiloffensis, Neptunea, 230, pl. 2qr prima, Cymatium (Dissentoma), 195 Primovula carnea, 181, pl. 22q princeps, Architeuthis, 483 princeps, Fasciolaria (see Pleuroploca), 242 proficua, Semele, 434, pl. qog profundorum, Abra, 32 Promartynia, 120 promera, Tellina, 424, fig. 86c Propeamussiidae, 369 Propeamussium, 361, 369 pourtalesianum, 369, pl. 27¢ protea, Aplysia, 285 protexta, Terebra, 266, pl. 26k Protobranchia, 332, 334 Protocardiinae, 399 Protonucula, 341 Protothaca, 410 grata, 411 laciniata, 410 ruderata, 410 staminea, 410, pl. 31m, n tenerrima, 410 proxima, Adalaria, 306, pl. 15-i proxima, Nucula, 334, fig. 70a, b proxima, Scissurella, g1, fig. 29 Prunum, 254 amabile, 256, fig. 56e apicinum, 257, pl. 11n, fig. 56g bellum, 256, fig. 56d borealis, 257 carneum, 254, 256, pl. 11k guttatum, 256, pl. 11m labiatum, 256, pl. 11-l limatulum, 257, fig. 56f roosevelti, 254, pl. 11-0 virginianum, 257, fig. 56h Psammobia, 441 Psammocola, 441 Psammosolen, 444 Psephidia, 411 lordi, 411, fig. 82a ovalis, 411, fig. 82b Pseudochama, 391 echinata, 393 exogyra, 393 ferruginea, 393 granti, 393 radians, 393, pl. 37c; fig. 79c¢ Pseudocyrena deans 381, pl. 30y pseudohexagonum, Dentalium, 330 Pseudomalaxis, 139 balesi, 139 nobilis, 139 Pseudomiltha, 387 Pseudoneptunea multangula, 211, fig. 47f Pseudopythina, 395 compressa, 395 rugifera, 395, fig. 80a psyche, Calliostoma, 113 Pteria, 359 colymbus, 359, pl. 35d sterna, 359 536 Pteriidae, 359 Pteropoda, 292 Pteropurpura, 205 Pterorytis, 218 foliata, 218, pl. 24h nuttalli, 219, pl. 24f Pterynotus, 205 pubescens, Colus, 229, pl. 23¢ pugilis, Strombus, 173, pl. sg pulchella, Tricolia, 127, pl. 1747 pulchella, Triphora, 159, pl. 19z pulchellum, Caecum, 147, fig. 37d pulcherrima, Acmaea, 106 pulchra, Rostanga, 300, pl. 16g pulchrum, Calliostoma, 112 pullata, Trivia, 177 Pulmonata, 310 punctata, Diplodonta, 383 punctatus, Octopus, 488 punctocaelatus, Acteon, 275 punctostriatus, Acteon, 275, pl. 26t punctulata, Acanthina, 211 punctulata, Acmaea, 106 punctulata, Bulla, 278 Puncturella, 94, 95 cucullata, 96, fig. 30a, b galeata, 96, fig. 30c noachina, 95 punicea, Tellina, 428 Pupillaria, 109 pupillus, Margarites, 109, fig. 31¢ Purpura, 213, 219 crispata, 215 foliatum, 219 pansa, 213 patula, 14, 213, pl. 25-1 purpurascens, Ischnochiton, 320 purpurascens, Semele, 435, pl. 4ob purpurea, Amauropsis, 188 purpurea, Gemma, 419 pusilla, Natica, 191, pl. 22) pustulata, Acmaea, 106 Pusula, 177 pycna, Olivella, 247 Pycnodonta hyotis, 374, pl. 38a pygmaea, Chione, 408 pygmaea, Colus, 229, pl. 23m pygmacus, Acanthochitona, 318 pyramidata, Clio, 295, fig. 64k Pyramidella, 288, 289 adamsi, 290, fig. 63a dolabrata, 289, pl. aq fusca, 288, fig. 62e Pyramidellidae, note 160, 288 Pyrenidae, 220 Pyrgiscus, 288, 290 Pyrgolampros, 290 pyriformis, Gibberulina, 260, fig. 56n Pyrula papyratia, 200 Pyrulofusus, 226 pyrum, Busycon, 236 Pyrunculus caelatus, 280, pl. 26w quadragenarium, Trachycardium, 398, pl. 31a Index Quadrans lintea, 430, fig. 86g quadrata, Philine, 283, fig. 59e quadridentata, Cavolina, 298, fig. 64s quadridentatus, Cadulus, 328 quadrifilatum, Bittium, 156 quadripunctata, Trivia, 178 quadrisulcata, Divaricella, 391, pl. 30m quoyanus, Perotrochus, 92 radians, Pseudochama, 393, pl. 37c; fig. 79¢ radians, Trivia, 179 radians, Trochita, 173 radiata, Ancistrosyrinx, 268, fig. 57e radiata, Glaucus, 309 radiata, Isognomon, 358, pl. 35a radiata, Pinctada, 359, pl. 35¢ radiata, Semele, 434, pl. 4of radiata, Tellina, 421, pl. 30e Raeta, 449 Ranella, 197 Rangia, 450 cuneata, 450, fig. 91a flexuosa, 450, fig. 91 nasuta, 450 rostrata, 451 Rangianella, 450 raninus, Strombus, 175, pl. 5c raveneli, Mitrella, 223, pl. 25ee raveneli, Pecten, 362, pl. 33g reclivata, Neritina, 129, pl. 4g reclusianus, Polinices, 187, pl. 20-i recurva, Clio, 295, fig. 64] recurvirostris, Murex, 202 recurvirostris rubidus, Murex, 202 recurvirostris sallasi, Murex, 202 recurvus, Brachidontes, 351, 353, pl. 35n redondoensis, Nuculana, 339 redondoensis, Venericardia, 379 reevei, Pleuroploca, 242 reeviana, Cavolina, 298 reflexa, Haloconcha, 131 regalis, Lischkeia, 110 regalis, Solariella, 110 regina, Tegula, 120, pl. 3f regius, Conus, 262, pl. 14m regularis, Ischnochiton, 322 regularis, Persicula, 258 Rehderia, 251 repanda, Cadlina, 302 reticularis, Oliva, 245, pl. 12¢ reticulata, Arca, 343 reticulata, Cancellaria, 252, pl. 13k reticulata, Ficus, 200 reticulata, Nucula, 335 reticulata, Peracle, 293, fig. 64g reticulatum, Tachyrhynchus, 140, 141 retifera, Amaea, 163, fig. god retroversa, Spiratella, 292, fig. 64c Retusa, 280 canaliculata, 280, pl. 26x candei, 280 obtusa, 280, 282, fig. 59a pertenuis, 280 sulcata, 280 turrita, 280 Retusidae, 280 revea, Haliotis, 93 reversa, Noetia, 346 reynoldsi, Epitonium, 165 rhizophorae, Crassostrea, 374, 375 Rhizorus, 280 acutus, 281, pl. 26-1 aspinosus, 281 bushi, 281 minutus, 281 oxytatus, 280 rhombica, Lamellaria, 175 rigida, Antigona, 405 rigida, Atrina, 360, pl. 27x Rimula frenulata, 95, fig. 30d Ringiculidae, 276 Ringicula, 276 nitida, 276 semistriata, 276, pl. 26v Rissoidae, 135 Rissoina, 136 bakeri, 137 browniana, 137 bryerea, 137 californica, 137 cancellata, 137 chesneli, 137 cleo, 137 coronadoensis, 137 dalli, 137 decussata, 137 kelyseyi, 137 laevigata, 137 multicostata, 137 newcombei, 137 sagraiana, 138 striosa, 137 ritteri, Trivia, 179 robustum, Dinocardium, 4o1, pl. 32a Rocellaria, 459 cuneiformis, 460 hians, 459 ovata, 460 Rochfortia, 395 roemeri, Donax, 437, pl. 30q rombergi, Strigilla, 429 roosevelti, Prunum, 254, pl. 11-0 rosacea, Hopkinsia, 307, pl. 16a rosaceus, Solen, 444 rosanum, Caecum, 148 rosea, Corbula, 459 rosea, Fissurella, roo, pl. 17e roseolum, Calliostoma, 112 Rossia, 479 equalis, 480 pacifica, 479 tenera, 480, fig. 99d Rostanga pulchra, 300, pl. 16g rostrata, Cuspidaria, 476, pl. 32} rostrata, Nettastomella, 464 rostrata, Poromya, 475 rostrata, Rangia, 451 rostrata, Spengleria, 460 rostratula, Ervilia, 452 rotella, Microgaza, 111, fig. 32d, e rotundata, Neritina, 130 rubella, Ostrea, 373 rubella, Rubellatoma, 272 Rubellatoma, 272 diomedea, 272 rubella, 272 ruber, Ischnochiton, 313, 322 rubrilineatum, Eulithidium, 127 rubropicta, Semele, 435, pl. 29w rubrum, Gastropteron, 283, fig. 60e ruderata, Protothaca, 410 rudis, Littorina, 133 rudis, Pinna, 360 rudis, Pododesmus, 372, pl. 38b Ruditapes, 410 rufescens, Haliotis, 92, pl. 2a (352) rufibranchialis, Coryphella, 310, pl. 15a rufoides, Ostrea, 374 rufus, Murex, 204 rugatina, Antigona, 405, pls. 38m, 32n rugosa, Ceratozona, 317, 326, fig. 67a rugosa, Hiatella, 453 rugosum, Trigonostoma, 253 rugosus, Octopus, 487 Rupellaria, 420 californica, 421 californiensis, 420 carditoides, 421 denticulata, 420 tellimyalis, 420, pl. 31t typica, 420, pl. 30e rupicola, Semele, 435, pl. 29t rupicolum, Epitonium, 165, pl. 22e rustica, Thais, 213, 214, pl. 25f rusticoides, Columbella, 220 Saccella, 338 sagitta, Penitella, 463 sagittata, Amygdalum, 353 sagra, Philine, 283 sagraiana, Rissoina, 138 Salasiella, 290 salleana, Terebra, 266, 267 salmonea, Tellina, 426, pl. 31y sanctaemarthae, Solecurtus, 445, pl. 30h sandersoni, Atys, 278, fig. 59d sandiegensis, Dialula, 301, pl. 16d sanguinea, Aldisa, 301 sanguinea, Trivia, 179 Sanguinolaria, 439 cruenta, 439, pl. god nuttalli, 439, pl. 29x sanguinolenta, 439 sanguinolenta, Sanguinolaria, 439 sanibelensis, Crassispira, 270 sapotilla, Yoldia, 340, pl. 276 satura, Chrysodomus, 229 satura, Neptunea, 229 saxatilis, Littorina, 133, pl. 19d Saxicava, 452 saxicola, Entodesma, 469, pl. 29m Saxidomus, 417 giganteus, 417 nuttalli, 417, pl. 31-1 Scientific Names sayana, Oliva, 245, pl. 12a sayi, Tellina, 424, fig. 86f scabra, Acmaea, 102, 103, pl. 18-1 scabra, Lima, 370, pl. oe re) scabra, Littorina, 133 scabra, Nuttallina, 314 Scala, 163 scalare, Epitonium, 6 Scalaria borealis, 162 scalariformis, Boreotrophon, 207 scalariformis, Cerithidea, 152, pl. 19x scalaris, Tegula, 118 Scalina, 163 Scaphella, 250, (273) butleri, 250 dohrni, 251, pl. 13) dubia, 251 florida, 251 georgiana, 251 johnstoneae, 250 junonia, 250, 251, pl. 13f schmitti, 251, pl. 13e scaphoidea, Limacina, 293 scaphoidea, Spiratella, 293 Scaphopoda, 327 Schizothaerus, 450 capax, 450 nuttalli, 450, pl. 31z Schizotrochus, 91 schmitti, Scaphella, 251, pl. 13e schrammi, Anodontia, 390 schrammi, Tonicia, 326, fig. 67e Scissula, 426 Scissurella, g1 crispata, 91 proxima, 91, fig. 29 Scissurellidae, 91 scitulus, Boreotrophon, 207, fig. 46d scolyma, Turbinella, 245 scolyma, Xancus, 245 Sconsia striata, 192, pl. gh scopulosum, Sinum, 190 Scrobiculina, 427 sculpta, Nuculana, 337 scutulata, Littorina, 134, pl. 20c scutum, Acmaea, 103, 104 Scyllaea pelagica, 308 Scyllaeidae, 308 Searlesia dira, 232, fig. sod secta, Macoma, 432, fig. 88c secticostata, Anadara, 345 Seila, 158 adamsi, 158, pl. 22t montereyensis, 158 terebralis, 158 Semele, 434 bellastriata, 435, pl. 30] cancellata, 435 decisa, 435, pl. 29z proficua, 434, pl. 4og purpurascens, 435, Pe 4ob radiata, 434, pl. 40 rubropicta, 435, pl. 29w rupicola, 435, pl. 29t semiaspera, Diplodonta, 383 53M Semicassis, 192 abbreviata, 193 inflatum, 193 semidecussata, Tapes, 411 seminuda, Odostomia, 288, fig. 62] Semirossia, 480 semistriata, Ringicula, 276, pl. 26v semistriolatum, Dentalium, 331 semisulcata, Papyridea, 398 semisulcata, Sigatica, 187 sennottorum, Conus, 261, pl. 14h sentis, Chlamys, 363, 364, pl. 34a Sepia, 480 sepioidea, Sepioteuthis, 482 Sepiolidae, 479 Sepioteuthis, 482 Septibranchia, 474, (332) Septifer, 354 bifurcatus, 353, 354 obsoletus, 354 serrata, Atrina, 360, pl. 27v serratum, Laevicardium, 400 serratus, Hipponix, 166 Serripes groenlandicus, 4o1, pl. 32d sicarius, Solen, 444, pl. 29v Sigatica, 189 carolinensis, 187, pl. 22-1 holograpta, 187 semisulcata, 187 signatum, Cyphoma, 184, pl. 4t Siliqua, 442 alta, 443 costata, 442, pl. 30f lucida, 442 media, 443 nuttalli, 443 patula, 442, pl. 29y squama, 442 siliqua, Cyrtodaria, 453 Siliquaria, 145 similis, Neosimnia, 183 similis, Spisula, 446 similis, Tellina, 426, pl. gom; fig. 86e simplex, Acmaea, 106 simplex, Anomia, 372, pl. 35k simpsoni, Pitar, 414 Sinum, 190 californicum, 190 debile, 190 maculatum, 190 perspectivum, 190, pl. 22s scopulosum, 190 sinuosa, Chama, 392, fig. 79a Siphonaria, 310 alternata, 310, fig. 65a lineolata, 310 naufragum, 310 pectinata, 310, fig. 65b Siphonariidae, 310 Siphonodentaliidae, 327 sitkana, Littorina, 134, pl. 2ob sloani, Strombus, 174 Smaragdia, 130 viridemaris, 130 viridis, 130, pl. 4h 538 weyssei, 130 smithi, Boreotrophon, 207 smithsoni, Haliotis, 93 solandri, Trivia, 179, pl. zou Solariella, 110 lacunella, 110, fig. 32b, c lamellosa, 110, pl. 17x obscura, 110, fig. 31f, g peramabilis, 111, fig. 31b regalis, 110 Solariorbis, 138 Solecurtus, 444 cumingianus, 444 sanctaemarthae, 445, pl. 30h Solemya, 333 borealis, 333 occidentalis, 333 valvulus, 333 velum, 333, pl. 278 Solemyidae, 333 Solen, 444 rosaceus, 444 sicarius, 444, pl. 29v vividis, 444, pl. 30n Solenidae, 442 soleniformis, Papyridea, 398, pl. 39u solida, Panope, 454 solidissima, Spisula, 446, pl. 32p solidula, Lacuna, 131 solitaria, Haminoea, 279, pl. 26s sombrerensis, Lucina, 385, fig. 78b sorenseni, Haliotis, 93 souleyetiana, Macoma, 432 sowerbii, Lucapina, 98, pl. 17h sowerbyi, Dentalium, 331 sozoni, Conus, 261, pl. 14¢ spadicea, Bursa, 198, pl. z5p spadicea, Cypraea, 180, pl. 6b spathulata, Barnea, 461 speciosa, Eucrassatella, 377, pl. 30z spectabilis, Strombus, 174 spectralis, Glycymeris, 348 spectrum, Acmaea, 104 Spengleria rostrata, 460 spenglerianus, Turbo, 123 sphaera, Neritina, 130 Sphenia, 455 fragilis, 455 ovoidea, 456 spiculosus, Acanthochitona, 318 spina-rosae, Epitonium, 165 spinosum, Crucibulum, 170, fig. 7-1 spinulosa, Astraea, 123, pl. 3m spirata, Acanthina, 211, pl. 24-0 spirata, Vermicularia, 144, pl. 21¢; fig. 22-1 Spiratella, 292 balea, 292 bulimoides, 293, fig. 64d gouldi, 292 helicina, 292, fig. 64a inflata, 293, fig. 64h lesueuri, 293, fig. 64b pacifica, 292 retroversa, 292, fig. 64c Index scaphoidea, 293 trochiformis, 292, fig. 64¢e Spiratellidae, 292 spiratum, Busycon, 236, pl. og Spiroglyphus, 144 annulatus, 144 lituellus, 144, pl. 20d Spirula spirula, 478, fig. 98 Spisula, 446 alaskana, 447 catilliformis, 448, fig. goc dolabriformis, 448, fig. goa falcata, 447 hemphilli, 448, fig. gob planulata, 448, fig. goe polynyma, 446, pl. 31w similis, 446 solidissima, 446, pl. 32p voyi, 447 spitzbergensis, Colus, 229, fig. 5th splendens, Calliostoma, 116, fig. 33¢ splendens, Haliotis, 93 splendidula, Haliotis, 92 Spondylidae, 369 Spondylus, 369 americanus, 369, pl. 36b dominicensis, 370 echinatus, 370 pictorum, 370, pl. 36a spreta, Ostrea, 373 springeri, Anadara, 345 spurca, Cypraea, 180 spurca acicularis, Cypraea, 180, pl. 6a spurius atlanticus, Conus, 260, pl. 14p spurius spurius, Conus, 260 squama, Siliqua, 442 squamatus, Tenagodus, 145, pl. 21g squamifera, Phylloda, 429, fig. 86h squamigerous, Aletes, 144, pl. 20e squamosa, Lima, 370 squamosus, Chiton, 324, 325 staminea, Protothaca, 410, pl. 31m, n stearnsi, Arctomelon, 251 stearnsi, Brachidontes, 353 stearnsi, Conus, 262, pl. 22y stearnsi, Ocenebra, 218 stearnsi, Venericardia, 379 stelleri, Amicula, 318, (51), fig. 66d stelleri, Cryptochiton, 318, 319 Stenoplax, 320 sterna, Pteria, 359 Sthenorytis, 161 cubana, 161 epae, 161 hendersoni, 161 pernobilis, 161 Sthenoteuthis bartrami, 484 stimpsoni, Colus, 227, pl. 23x stimpsoni, Conus, 263, pl. 14) stimpsoni, Transennella, 412, fig. 83a, b stokesi, Chiton, 326 Stramonita, 213 striata, Bulla, 277, pl. 13p striata, Donax, 438 striata, Hiatella, 453, fig. g2b striata, Hyalocylis, 294, fig. 64q striata, Lacuna, 131 striata, Martesia, 464, pl. 32w striata, Sconsia, 192, pl. gh striatum, Crucibulum, 169, 170, pl. 21r stricta, Turbonilla, 288, fig. 62c strigatella, Acmaea, 103 Strigilla, 428 carnaria, 428, pl. goc flexuosa, 429 mirabilis, 429 pisiformis, 429 rombergi, 429 strigillina, Antigona, 404, pl. 38-1; fig. 81d striosa, Rissoina, 137 Strioturbonilla, 290 Strombidae, 173 Strombus, 173 alatus, 174, pl. 5h bituberculatus, 175 canaliculatus, 174 costatus, 174, pl. 23b gallus, 175, pl. se gigas, 174, pl. 23a goliath, 6 horridus, 174 peculiaris, 174 pugilis, 173, pl. 5g raninus, 175, pl. 5c sloani, 174 spectabilis, 174 verrilli, 174 stuarti, Boreotrophon, 207, pl. 24; stultorum, Tivela, 412, pl. 31h; oe 28d Stylidium, 155 Styliferidae, note 160 Styliola, 294 conica, 294 subula, 294, fig. 64-0 vitrea, 294 styria, Mitra, 248 subcoronata, Melongena, 235 subdiaphana, Compsomyax, 411, pl. 3if subdiaphana, Cooperella, 421 subequilatera, Astarte, 375, 376, pl. 28-0 © subglobosa, Navea, 464 subobsoleta, Glycymeris, 349, pl. 31¢e subquadrata, Diplodonta, 383 subrostrata, Trivia, 178 subrufus subrufus, Hipponix, 166 subrufus tumens, Hipponix, 166 substriatum, Laevicardium, 400 subteres, Tagelus, 441, pl. 29s subtrigona, Persicula, 258 subula, Styliola, 294, fig. 64-0 subulata, Cerithiopsis, 157, pl. 19w subumbilicatum, Calliostoma, 113 subviridis, Lasaea, 353, 395 succincta, Chione, 408 succinctus, Margarites, 109, fig. 31a » succinea, Haminoea, 279 succinea, Hyalina, 259 suffusa, Lucapina, 98, pl. 17k suffusa, Trivia, 177, 178, pl. 21aa sulcata, Limopsis, 347, pl. 27f sulcata, Mitra, 232, 249, pl. 26a sulcata, Retusa, 280 sulcidentata, Eupleura, 219, fig. 47¢ sulcosa, Anadara, 345 Sulcosipho, 231 sulphurea, Ancula, 306 superba, Gaza, 118, pl. 3b Supplanaxis, 150 supragranosum, Calliostoma, 115, pl. 18s Susania, 286 swainsoni antillensis, Mitra, 248 swifti, Colubraria, 233 swifti, Epitonium, 163 swiftiana, Corbula, 458, fig. 93b sybaritica, Tellina, 424, fig. 86d _ sybariticum, Laevicardium, 400 | Sycofulgur, 236 Symmetrogephyrus, 316 pallasi, 317 vestitus, 316, fig. 66c Syrnola, 288 ' tabulata, Neptunea, 231, fig. 51f Tachyrhynchus, 140 rn es Ory ‘ | i erosum, 140, 141, pl. 21-1 lacteolum, 141 reticulatum, 140, 141 taeniata, Panope, 454 Taenioturbo, 123 Tagelus, 440 affinis, 440 californianus, 440, pl. 29u divisus, 440, pl. 30g gibbus, 440 plebeius, 440, pl. 30d politus, 441 subteres, 441, pl. 29s tampaense, Calliostoma, 113 tampaensis, Crassispira, 270 tampaensis, Tellina, 424, fig. 86b tampaensis, Urosalpinx, 213 tantilla, Transennella, 413 _ Tapes, 410 bifurcata, 411 philippinarum, 410 semidecussata, 411 _taphria, Nuculana, 338, fig. 72a, b Taras orbella, 383 taurinum, Terebra, 265, pl. 13h _Taxodonta, 341 | Tectarius, 134 muricatus, 134, pl. 19g tuberculatus, 134 - Tectibranchia, 275 _ Tectininus, 135 Tegula, 118 aureotincta, 120, pl. 18k brunnea, 119, 120 excavata, 119 fasciata, 118, pl. 17p funebralis, 104, 119 gallina, 119, pl. 18r hotessieriana, 119 indusi, 118 Scientific Names ligulata, 120, pl. 18h lividomaculata, 118 marcida, 120, pl. 18y montereyi, 120, 121, pl. 18x regina, 120, pl. 3f scalaris, 118 tegulus, Nassarius, 238, pl. zon Teinostoma, 139 biscaynense, 140 clavium, 140 cocolitoris, 139 gonlogyrus, 140 leremum, 140 litus-palmarum, 139 nesaeum, 140 obtectum, 140 parvicallum, 140 pilsbryi, 140 telemus, Cavolina, 296 tellea, Polystira, 268, pl. 13m Tellidora cristata, 430, pl. 30-0 tellimyalis, Rupellaria, 420, pl. 31t Tellina, 421 agilis, 422, pl. 30x; fig. 86f alternata, 427, pl. gon angulosa, 428 buttoni, 425 candeana, 427 carpenteri, 426 decora, 426 elucens, 423 fausta, 428 idae, 422, figs. 87a, 28h interrupta, 422, pl. 4o-l iris, 427 laevigata, 422, pl. 4ok lineata, 427, pl. goh lutea, 425, fig. 86c, d magna, 427, pl. 4o-i mera, 423, fig. 86c meropsis, 426, pl. 30w modesta, 425, pl. 31u polita, 424 promera, 424, fig. 86c punicea, 428 radiata, 11, 421, pl. goe salmonea, 426, pl. 31y sayi, 424, fig. 86f similis, 426, pl. 4om, fig. 86e sybaritica, 424, fig. 86d tampaensis, 424, fig. 86b tener, 422 tenera, 422 texana, 423, 424 venulosa, 425 versicolor, 423 Tellinella, 422 tellinoides, Cumingia, 436 Tenagodidae, 144 Tenagodus, 145 modestus, 145 squamatus, 145, pl. 21g tener, Angulus, 422 tenera, Acmaea, 106 tenera, Barbatia, 343, pl. 27k yo tenera, Heteroteuthis, 480 tenera, Lima, 371 tenera, Rossia, 480, fig. 99d tenera, Tellina, 422 tenerrima, Protothaca, 410 tenerum, Trigonostoma, 253, fig. 55d tenta, Macoma, 431 tenue, Buccinum, 225, 226, pl. 2au tenuirostris, Macoma, 432 tenuis, Amphithalamus, 136 tenuis, Nucula, 335, fig. 70c tenuisculpta, Alabina, 158 tenuisculpta, Bursa, 198 tenuisculpta, Lucina, 387, fig. 78h tenuisculpta, Ocenebra, 209 tenuisculptus, Trophon, 209 tenuisculptus, Trophonopsis, 209 tenuisulcata, Nuculana, 336, fig. 71a Terebra, 265, (158) cinerea, 266, pl. 26g concava, 266, pl. 26] dislocata, 265, pl. 26-i feldmanni, 265 flammea, 265 floridana, 265 hastata, 266, pl. 26h limatula, 266 lutescens, 266 pedroana, 267 protexta, 266, pl. 26k salleana, 266, 267 taurinum, 265, pl. 13h terebralis, Seila, 158 Terebridae, 265 Teredinidae, 465 Teredo, 467 bartschi, 467 diegensis, 467 navalis, 467 townsendi, 468 tereinus, Pecten, 363 Tergipedidae, 308 Tergipes despectus, 309, pl. 15d terricula, Odostomia, 290, fig. 63-0 tessellata, Nerita, 128, 129, pl. 4f tessellata, Tricolia, 127 tessulata, Acmaea, 104, 105 testacea, Colubraria, 233 testiculus, Cypraecassis, 194, pl. 9c testudinalis, Acmaea, 104, 105 Tethys, 285 Tetrabranchia, 478 tetrica, Lima, 370 texana, Mercenaria, 406 texana, Tellina, 423, 424 texasiana, Callocardia, 416, pl. 32k; fig. 28e texasianum, Dentalium, 329, fig. 6ge ‘Whais, 203 canaliculata, 216, fig. 48b, c crispata, 215 deltoidea, 214, pl. 25b, k emarginata, 216, fig. 48a haemastoma, 213 haemastoma floridana, 213, 214, pl. 25a 540 haemastoma haysae, 213 imbricatus, 215 lamellosa, 215, 216, figs. 48e-h lapillus, 214, pl. 25g lima, 216, fig. 48d rustica, 213, 214, pl. 25f undata, 213 thea, Cerodrillia, 270, fig. 57f Thecosomata, 292 Thericium, 153 Thestyleda, 339 thomae, Bursa, 197 thomasi, Ostrea, 374 Thracia, 471 conradi, 471, pl. 28y curta, 472 trapezoides, 471 thraciaeformis, Yoldia, 340, pl. 27e Thyasira, 384 bisecta, 384, fig. 77a disjuncta, 385 gouldi, 384 trisinuata, 384 timessus, Fusinus, 243, pl. 11g Timoclea, 408 tinctum, Microcardium, 399 tinctus, Cantharus, 214, 233, 234, pl. 25y Tindaria brunnea, 341 Tivela, 412 crassatelloides, 412 floridana, 412 stultorum, 34, 412, pl. 31h tollini, Epitonium, 164 Tonicella, 312, 313, 322 lineata, 312, 313 marmorea, 312, 313, 322 Tonicia schrammi, 326, fig. 67e Tonna, 199 album, 199 brasiliana, 199 galea, 199, pl. 23f maculosa, 199, pl. 9d perdix, 199 Tonnidae, 199 Torcula, 141 Torinia, 142 bisulcata, 142, pl. 21x cylindrica, 142 torticula, Hyalina, 259, fig. 56-1 townsendi, Yeredo, 468 Trachycardium, 397 egmontianum, 397, pl. 39-0 isocardia, 397 magnum, 397 muricatum, 397, pl. 39p quadragenarium, 398, pl. 31-0 Transennella, 412 conradina, 413, fig. 83c stimpsoni, 412, fig. 83a, b tantilla, 413 translirata, Anachis, 221, pl. 25ff transversa, Anadara, 345, pl. 27s Trapeziidae, 382 trapezoides, Thracia, 471 Tremoctopus violaceus, 485 tremperi, Murex, 205 Index trialatus, Murex, 205, fig. 45c triangularis, Acmaea, 104 triangulatus, Boreotrophon, 208, fig. 46b Trichotropidae, 167 Trichotropis, 167 bicarinata, 168, pl. 24a borealis, 167, pl. 24d cancellata, 167, pl. 24b insignis, 168, pl. 24c Tricolia, 126 affinis, 126 compta, 127 concinna, 127 pulchella, 127, pl. 17£ tessellata, 127 variegata, 128 tricolor, Calliostoma, 113, fig. 33¢ tridentata, Cavolina, 296, fig. 64u tridentata, Turbonilla, 290, fig. 63f tridentata, Venericardia, 379, 380 trifida, Odostomia, 288, fig. 62f Trigoniocardia, 398 biangulata, 399 medium, 398, pl. 39m Trigonostoma, 253 rugosum, 253 tenerum, 253, fig. 55d Trigonulina, 474 trilineata, Pandora, 469, fig. 96b Triopha, 304 carpenteri, 304, pl. 16k grandis, 304, pl. 16b maculata, 304, pl. 16f Triphora, 159 decorata, 159, pl. 192z nigrocincta, 159, pl. 19y ornatus, 159 pedroana, 159 perversa, 159 pulchella, 159, pl. 19z Triphoridae, 159 triquetra, Parastarte, 419, fig. 85 triseriata, Lunatia, 189, pl. 22m trisinuata, Thyasira, 384 trispinosa, Cavolina, 298, fig. 64t Tritonalia, see Ocenebra, 216 tritonis, Charonia, 197 tritonis nobilis, Charonia, 197, pl. 5f Tritoniscus, 196 Tritonocauda, 196 Trivia, 177 antillarum, 178 armandina, 177 californiana, 179, pl. 20v candidula, 178, pl. 21ec globosa, 178 leucosphaera, 178 maltbiana, 178, pl. 21z nivea, 179 nix, 178, 179 pediculus, 177, pl. 21bb pullata, 177 quadripunctata, 178 radians, 179 ritteri, 179 sanguinea, 179 solandri, 179, pl. 20u subrostrata, 178 suffusa, 177, 178, pl. 21aa trivittatus, Nassarius, 239, pl. 23] Trochidae, 107 trochiformis, Spiratella, 292, fig. 64e trochiformis, Xenophora, 173 Trona, 180 Trophon tenuisculptus, 209 Trophonopsis, 208 lasius, 208 tenuisculptus, 209 Truncacila, 336 truncata, Barnea, 461 truncata, Mya, 455, pl. 32v trunculus, Murex, 12, 13. pl. 10-i tryoni, Aequipecten, 367 tryoni, Murex, 202 tryomi, Pecten, 367 tuber, Astraea, 124, pl. 3} tuberculata, Nodilittorina, 134, 135, pl. 19-1 tuberculatus, Chiton, 324, pl. 1d; fig. 67£ tuberculatus, Tectarius, 134 tuberosa, Cassis, 193 tuberosa, Mitrella, 223 tuberosum, Cymatium, 196 Turbo, 123 canaliculatus, 123, pl. 3a castaneus, 123, pl. 3g crenulatus, 123 spenglerianus, 123 tulipa, Fasciolaria, 242, pl. 13b tulipa, Modiolus, 351 tulipa, Volsella, 351 tumida, Donax, 438 tumida, Mysella, 397, fig. 80b tunicata, Katharina, 316, fig. 66b turbinella, Engina, 232, pl. 25w, (249) — Turbinella scolyma, 245 Turbinidae, 121 Turbonilla, 288 acra, 290, fig. 63c aragoni, 290, fig. 63k buttoni, 290, fig. 63d chocolata, 290, fig. 63e interrupta, 288, fig. 62b kelseyi, 290, fig. 63b laminata, 290, fig. 63-1 nivea, 288, fig. 62d stricta, 288, fig. 62c tridentata, 290, fig. 63f Turcicula, 109 Turridae, 267 turrita, Cerithidea, 152 turrita, Retusa, 280 Turritella, 140 acropora, 141, pl. ee) cooperi, 141, 142, pl. 20g exoleta, 141, pl. 21h mariana, 142, pl. 2oh variegata, 141, pl. 21-1 Turritellidae, 140 Turtonia minuta, 41 turveri, Haliotis, 93 ee Tutufa, 198 typica, Rupellaria, 420, pl. 30e uberinus, Polinices, 185 umbilicalis, Margarites, 108 umbonata, Arca, 342, pl. 27) uncinata, Cavolina, 298, fig. 64x uncinatif ormis, Cavolina, 298 undata, Amphissa, 224, fig. 50c undata, Astarte, 376, pl. 28r undata, Glycymeris, 348, 349, pl. 27g undata, Micromelo, 276, pl. 26u undata, Thais, 213 undata, Velutina, 175 undatella, Chione, 408, pl. 31-i undatum, Buccinum, 225 undosa, Astraea, 124, pl. 18p undulata, Cyathodonta, 472, pl. 31s unifasciata, Lacuna, 131, fig. 36b uniplicata, Neosimnia, 182, pl. 7e universitatis, Glossodoris, 303 urceolaris, Herse, 299 Urosalpinx, 212 cinerea, 212, fig. 47e follyensis, 212 perrugata, 211, 212, fig. 47d tampaensis, 213 vaginata, Nuculana, 337 vallei, Cypraea, 180 valvulus, Solemya, 333 vancouverensis, Acteon, 275 vanhyningi, Arene, 122 vanhyningi, Cerithiopsis, 157 vanhyningi, Conus, 263 vanhyningi, Cumingia, 436 vanhyningi, Dinocardium, 4o1, pl. 32b Vanikoro oxychone, 167 Vanikoroidae, 167 variabile, Cerithium, 154, pl. 19-0 variabilis, Arene, 123, pl. 17s variabilis, Donax, 437, pl. 30r variabilis, Neosimnia, 183 Varicorbula, 456 disparilis, 457 operculata, 456 variegata, Eulithidium, 128 variegata, Lacuna, 131 variegata, Mitrella, 223 variegata, Nerita, 128 variegata, Tricolia, 128 variegata, Turritella, 141, pl. 21-1 variegatum, Calliostoma, 116, fig. 33b varium, Bittium, 155, pl. ror Vasum, 245 coestus, 245 muricatum, 245, pl. 23-1 velata, Placiphorella, 316, fig. 66a velei, Cymatium, 195 veliei, Hyalina, 258 velum, Solemya, 333, pl. 27a Velutina, 131, 175 laevigata, 175, pl. 22n undata, 175 zonata, 175 Venericardia, 379 Scientific Names borealis, 379, 380, pl. 28t flabella, 380 novangliae, 378 perplana, 380, pl. 28-1 redondoensis, 379 stearnsi, 379 tridentata, 379, 380 ventricosa, 379, pl. 29-l Veneridae, 404 ventricosus, Colus, pl. 23u, not in text ventricosa, Neptunea, 230, pl. 24s ventricosa, Venericardia, 379, pl. 29-1 venulosa, Tellina, 425 Venus, see Mercenaria, 406 venustula, Arene, 122 Vermetidae, 143 Vermicularia, 144 fargoi, 145, pl. 21b knorri, 145, pl. 21a spirata, 144, pl. 21¢; fig. 22-i verrilli, Strombus, 174 versicolor, Amphissa, 223, 225, fig. 50a versicolor, Cerithium, 154 versicolor, Nerita, 128, pl. 4b versicolor, Tellina, 423 Verticordia, 474 fisheriana, 474 ornata, 474, fig. 97c, d Vesica, see Bulla, 277 vesicaria, Hydatina, 276, pl. 13q vesicula, Haminoea, 279 vestitus, Symmetrogephyrus, 316, fig. 66c viabrunnea, Genota, 271, fig. 57g vibex, Nassarius, 237, pl. 23q villepini, Conus, 263, pl. r4f vincta, Lacuna, 130, 131, pl. 22p; fig. 36c-e violaceus, Tremoctopus, 485 virescens, Haminoea, 279 virescens, Voluta, 250 virginea, Neritina, 129, pl. 4-1 virginianum, Prunum, 257, fig. 56h virginica, Cerithiopsis, 157 virginica, Crassostrea, 373, 375, pl. 28a virginicum, Bitttum, 155 virgo, Polystira, 268 virgula, Cleodora, 294 virgula, Creseis, 294, fig. 64p virgulatus, Chiton, 324 viridemaris, Smaragdia, 130 viridis, Chiton, 325 viridis, Smaragdia, 130, pl. 4h viridis, Solen, 444, pl. 30n vitillina, Erato, 176, pl. 20-0 vitrea, Creseis, 294 vitrea, Styliola, 294 Vitrinella, 138 beaui, 138 helicoidea, 138 multistriata, 138, pl. 17Vv Vitta, 129 volcano, Fissurella, 100, pl. 18c Volsella, 351 americana, 351, 352, pl. 35-1 capax, 352 541 demissa, 351, pl. 38h demissa granosissima, 352 fornicata, 352, pl. 29-0 modiolus, 351, fig. 26} plicatula, 352 tulipa, 351 Voluta, 250 musica, 250, pl. 13g virescens, 250 Volutharpa ampullacea, 78 Volutidae, 250 Volutopsius, 226 castaneus, 226, fig. 51c harpa, 226, pl. 24p Volvarina, 258 Volvula, see Rhizorus, 280 Volvulella, see Rhizorus, 281 voyi, Spisula, 447 vulgaris, Octopus, 486, fig. 100a wallallensis, Haliotis, 93 washingtona, Xylophaga, 463 watsoni, Gaza, 118, fig. 32a weyssei, Neritina, 130 weyssei, Smaragdia, 130 willcoxi, Aplysia, 285 willisi, Odostomia, 288, fig. 62a wosnessenski, Mopalia, 315 wroblewskii, Opalia, 162, pl. 20] Xancidae, 244 Xancus, 244 angulatus, 244 scolyma, 245 Xenophora, 172 caribaeum, 173, pl. 23e conchyliophora, 173, pl. 5b longleyi, 173, pl. 23d radians, 173 trochiformis, 173 Xenophoridae, 172 Xylophaga, 463 dorsalis, 463 washingtona, 463 Yoldia, 340 limatula, 340, fig. 71b, (44) limatula gardneri, 340 myalis, 340, pl. 27d sapotilla, 340, pl. 27b thraciaeformis, 340, pl. 27¢ yoldiformis, Macoma, 433 Zaphon, 240 zebra, Arca, 342, pl. 27n zebra, Cypraea, 180, pl. 6d Zeidora, 94 ziczac, Littorina, 132, pl. 19e ziczac, Pecten, 362, pl. 33d Zirfaea, 462 crispata, 462, fig. 94c, 461 gabbi, 462 pilsbryi, 462 zonamestum, Calliostoma, 112, pl. 2n Zonaria, 181 zonata, Velutina, 175 a —_— a ae i ne Oh pee ye 0 22 oe gies ee Uf USEFUL INFORMATION FOR THE CONCHOLCGIST 1 inch (English) 1 pouce (French) 1 pollex (Latin) 1 Zoli (German) 1 Ligne (French) = 2.25 mm. 1 line (English) = 2.11 mm. 1 linie (German) = 2.18 mm. 3’ 4” 6” means 3 ft., 4 inches, 6 lines Pench — 25:37 mm. = 12 lines ref = male ° = female g = hermaphrodite t@————— LENGTH OF SHELL, ————>4 1 fathom = 6 feet I meter = 39.37 inches 1 nautical mile = 6,080 feet I statute mile = 5,280 feet 1 degree latitude = 60 nautical miles or about 69 statute miles Temperature conversion (Fahrenheit-Centi- grade) == 2 C+ 32 5 = 3 (F—32) ia th whit) Hit 3 Hat Hy) eh