East Coast Marine Shells : Descriptions of Shore Mollusks Together With
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6 ^O s m xZ -1= E a CD- Si i : m MBL Syste^na'bs Esslosy EAST COAST MARINE SHELLS ..R • .-fi'" '\^ // •: M :V:;:--::.^ e p "I have seen A curious child, who dwelt upon a tract Of Inland ground, applying to his ear The convolutions of a smooth-lipp'd shell; To which in silence hush'd, his very soul Listen'd intensely and his countenance soon Brightened with Joy: for murmerings from within Were heard, — sonorous cadences, whereby. To his belief, the monitor express'd Mysterious union with its native sea." Wordsworth ii 6}L EAST COAST MARINE SHELLS Descriptions of shore meliusks together with many living below tide mark, from Maine to Texas inclusive, especially Florida With more than one thousand drawings and photographs By MAXWELL SMITH Fourth Edition Revised 1951 EDWARDS BROTHERS, INC. ANN ARBOR, MICHIGAN 1951 Copyright 1937 MAXWELL SMITH I.ithoprintt'ti in U.S.A. EDWARDS BROTHERS, INC. ANN ARBOR, MICHIGAN 1 95 1 INTRODUCTION Wno has not felt the urge to explore the quiet lagoon, the .sandy beach, the coral reef, the Isolated sandbar, the wide muddy tidal flat, or the rock-bound coast? How many rich harvests of specimens do these yield the collector from time to time? This volume is intended to answer at least some of these questions. From the viewpoint of the biologist, artist, engineer, or craftsman, shellfish present lessons in development, construction, symme- try, harmony and color which are almost unique. To the novice an acquaint- ance with these creatures will reveal an entirely new world which, in addi- tion to affording real pleasure, will supply much of practical value. Life is indeed limitless and among the lesser animals this is particularly true. A mighty pattern is being woven into which signifi- cantly fits the smallest organism, which under the microscope reveals for a moment its importance in the lengthy chain. Some of these units may dis- appear from the surface of the earth and be replaced by others. This con- stant weaving, building up a liftle here and tearing down some there, con- stitutes what some may designate as evolution. Adaptation does not neces- sarily express the conformity of a species to its environment. Local con- ditions influence the mode of life to a very marked extent. Sustenance, pigmentation, a-nd amount of lime available for shell building are reflected in succeeding generations. Different conditions in various localities often result in abnormal size, stunted growth or peculiar color patterns. Allowance should be made for these influences where peculiar conditions pre- vail. Giants or dwarfs may readily be recognized. Each individual reader or student may actually assist in adding to the knowledge of American shells. With the span of human life comparatively short it is better for individuals to specialize, more or less, rather than attempt to cover a very broad field. Intensive and reg- ular local observations will prove more productive than those carried on some distance away. The English realize this and their tiny island has not yet revealed all of its secrets. The broad American continent needs naturalists in every community to complete the census of animals and plants. Long stretches of coastline upon the Atlantic and Gulf have never been Intelligently worked for shells. The collector will eventually wander into new fields and find the opportunities for recording data endless. This service consists, in one way, of making careful records of the habits of even the common species. A well-known authority estimates that eventually a hundred thousand mollusks will be known, against the sixty thousand odd species which have already been described. These figures are given not to discourage the beginner but to suggest the work in which he may assume a share. It will be noted that not all the species of a given genus appear together in the illustrations contained in this volume. With a shell in hand for comparison it will be best to run through all the plates, at first, until a figure approximating the specimen is found. Then refer- ence to the text will permit comparison with the diagnoses of the group. The individual species may be studied in turn the last of all. With a lit- tle knowledge and practice it should soon be possible for the reader to as- sign the larger shells fairly close to their actual position in the text. vi EAST COAST MARINE SHELLS Juvenile shells often exhibit the characters of their elders and, there- fore, can be Identified. At times, species are encountered which present in the young stages quite a different aspect from the adult. Then connect- ing series are necessary to show the correct relationship. A number of years have passed since the appearance of a work covering the shells of the American east coast. Many recent additions to the fauna have led the author to compile for his use check lists of local material secured in New England and the various southern states. With these lists as a nucleus it has been necessary to prepare descriptions of the various species and the families under which they are grouped. Some of the descriptions were obtained from the source, the original author's work often contained in some obscure journal or monograph. A considerable number of photographs of east coast shells have been taken personally by the writer for the present volume. Many of these subjects are in his pri- vate collection, others in museums in various parts of the country. The majority of the specimens illustrated were collected upon the mainland of the United States and verified by the finders. Most of the deep water forms are housed in the National Museum. No doubt errors occur, both in the identifications of the little-known species and in certain nomenclature. The aid of students is sought in the correction of mistakes. Only with the assistance of all may the truthful mirror of life be presented. The author is deeply grateful to many friends for helpful suggestions together with the loan and donation of specimens, especially to: Dr. Henry A. Pilsbry of the Academy of Natural Sciences, Philadelphia; Prof. William J. Clench of Harvard University; Joshua L. Baily, Jr., of San Diego, California; Dr. Paul Bartsch and Dr. H. A. Rehder of the National Museum, Washington, D.C.; Dr. Louise Perry of Sanibel. Florida; Dr. George A. Water- man of Palm Beach, Florida; Paul P. McGinty and his sons Paul L. McGinty, and Thomas L. McGinty, of Boynton, Florida; Mr. and Mrs. Frank Lyman and Jack Lyman, of Lantana; and Albert Pflueger of Miami, Florida. The writer Is particularly Indebted to Thomas L. McGinty for many fine drawings which accompany the text, also the map of Florida which he so painstakingly pre- pared, and to Miss Elizabeth Pilsbry, daughter of the distinguished malacol- ogist Dr. Henry A. Pilsbry for the illustration accompanying the Wordsworth quotation. Without the cooperati^in of these and manjr other earnest workers the records within these pages would be far less complete. Lantana, Florida, November 15, 1936. TABLE OF CONTENTS Page Introduction ^ Instructions for Collecting Mollusks 4 Univalves— Position for Study H ^^ Bivalves "^"^ Class Amphineura . ^^ Class Pelecypoda Class Scaphopoda '^-'- 74. Class Gastropoda Class Cephalopoda ^^^ Plates ^^^ Glossary of Descriptive Terms and General Index 303 Index of Genera, Subgenera, and Sections 307 vii . EAST COAST MARINE SHELLS The term CONCHOLOGY Is derived from Originally bilaterally symmetrical a combination of two Greek words "A Shell organisms the Influence of environment has Fish" and "Science of." It is usually ap- often resulted in radical readjustments of plied to the study of both animal and internal organs with consequent modifica- shell. Another word, MALACOLOGY has Deen tions in the shell. accepted by many societies and individuals PELECYPODA^ or BIVALVES. Entirely to supersede the earlier one and refers aquatic and predominately marine forms. The also to the study of the entire organism. term bivalve indicates a two-piece shell. The MOLLUSCAN PHYLUM comprises LAMELLIBRANCHIATA, which is also frequent- those animals with soft fleshy bodies cov- ly applied to this group, refers to the ered by a muscular sac, commonly called the lamellar or leaf-like character of their mantle, and which usually secretes a shell branchial gills. The tongue-like foot used composed of carbonate of lime which in for ploughing through mud or sand is char- turn affords protection to the vital organs acteristic, also the elastic ligament which of the body. binds the valves together, and the inter- POSITION OF THE MOLLUSCA. Cr. Rob- locking teeth or denticles at the hinge. ert W. Hegner in "College Zoology" places Examples: oyster, scallop, and clam. the Phyla of the Mollusca between the An- SCAPHOPODA^ or TUSK SHELLS. Animal nelida (a group to which belong the jointed with long filaments appearing from lobes worms) and the Arthropoda (which includes about the neck and enveloped, with the head, the crabs, insects, etc.). The three share by the mantle. Shell tubular, not spiral. one character in common, they are, or orig- Example: Dentalium (Elephant's Tusk Shell). inally were, mostly bilaterally symmetrical AMPHINEURA.^ Sometimes placed un- organisms. der the Gastropoda. The Chitons or coat- DIVISIONS or THE MOLLUSCA. There of-mail shells are externally bilaterally are five great classes indicated by the symmetrical. They usually are provided variations of the foot or locomotive organ "vith a shell of eight transverse calcare- and named: CEPHALOPODA, GASTROPODA, SCA- ous plates. PHOPODA, PELECYPODA, ^nd AMPHINEURA. SUMMARY. A superficial examina- cephalopoda! or CEPHALOPODS. Ani- tion reveals little in common to the pre- mal with foot lacking or rudimentary, pos- ceding classes. However, there are several sibly modified to arms of which there are structures shared by all, notably the foot.