The Conchologist’s First Book — Edgar A. Poe, 1839 — reading text

form, are not devoid of interest, ; $e for without seeking here to resolve the physiological question— 3 a whether the conchyliferous mollusea borrow of the inorganic king- ye : dom the ealeareous matter which composes their shells, or whether =" they form it of themselves, it is still certain that they produce, at least, changes upon the surface of the earth by rte this — ‘ ~~ material i in some i more than in others, and in ‘consequence » 8 INTRODUCTION. that they alter the physiognomy of the superficial structure of the globe, the study of ‘which constitutes geognosy.”” “ By this,” says Parkinson, “we are taught that innumerable beings have lived, of which not one of the same kind does any longer exist—that immense beds composed of the spoils of these animals, extending for many miles under ground, are met with in many parts of the globe—that enormous chains of mountains, which seem to load the surface of the earth, are vast monuments, in which these remains of former ages are entombed—that, though lying thus crushed together, in a rude and confused mass, they are hourly suffering these changes, by which, after thousands of years, they become the chief constituent parts of gems, the lime- stone which forms the humble cottage of the peasant, or the mar- ble which adorns the splendid palace of the prince.” Fossil, wood, coral, and shells, are, indeed, as Bergman has very forcibly remarked, the only true remaining “ medals of Creation.” % Pi + Bells, oe a >) PAT. fs OL BS Paves ?S Daval Lith. Paw “LP US oF SHOldss. PS. Duval tlle let? a) ity » LALA ws ~ > PS Div, LT) 1 Siig niuria 2 Dentalum. SlectinarvriaASiubcllervia, iTerebeila. OAmphiirite. 7 Sbirorbis. & Serputla, IVermitia. Ub Gulectaria. UMMagilus. /2 Ticbicinella. (3 Corenutla lp Batlanis B.Acast. 10 Creusia si Lyrgcmea. IS Anativer a /9 Fold. zcepes. 20 Gneras. 2/ Olin. 22Aspergillum. LS. Duval, Lethe Phil 4 Clavagella. 2fFistitant. & Septlaria .4 leredina~ 3leredo. OPhotas./ Castrochena. & Seler.9 Lapopean. Solecw- -leus. MM Clyceméris. (2 Mya. leAnatind: 14 LUT aria. t3Muctra. (6 Crassadetlai (7 kryucina. /§ CrguAane DSolenimya. UWA plidesnra. 2! borbuta. 226 an aon. 902 «A 2 LO SARLICAVA. LS. Duval, Lith 2 Phil t Letricda. 2eneriripis. SSanguinclira. 41ammobvia ILTsammetea. 6 Tellina./ lellinides. § C0rOtS. 9 LUCIE. /0 Denacs 1 Capsa. 12 Crasstnra, 18 Cy clas. by ly rere (3 Gatathea: 16 Cyprina./i Cytherea: 18 bérzits LOL EME7% = cardia. 20bardiur. 2/ Cardita.22 Cypricaracead. 23 Hravedia. LF. S. Duval, Lith? Fils AL80CATraz a. Of idler. R Arta. 4 LeCCOuUM CIM US. 5 Vetcol ex 6 lrigoria 7 Castabin, P52 0.2 urz. MAnCACnIA. M Lriding, (2 Dicerus. {24 itt bg htheria: 18 Pridaepe MO ipbopits. Ji: Mytilus. (SF Midicla $p9 Franz. XC Crenateclae 2/ lérna: £2 UMatieus. = 2 ? F-32 rmzssa L°S, Drevad, Little! f Ril] ka miiseay MAN, Pe /, Avicutla,. 2 Meleagrina: Sledum. 4 Lira. 5&ecI en. OL lagestorw. (Plicatula. §Spondylus.. 9GTY phew . 10 Ostrex. [1 Viuselta.. /27¥lacuna. /(sAnomia. li Crunin. WOrbtcula . sO Terebraiuia. Vi Lingule./S THyadler. WI Clecdorvn. 20 Ltmacina. 2/ Cymbelia. 22 Chitonellis. 23 Chtton. 24 Fiutetla . 25 Pleurcbranchis. 26 Vintreila. 27 Lliaavrragbherus. 2F Brrrginita, 29 Pissvrella LS. Duval. Tith* Pid # Wer wet lye fat 4 IF 1 Peleopsrs. 2 Calyplera.3 Cdadule. gA7 cylius. 5 Bullen. CB2tlli. TA plysew. & Delabella. Wiaprriacelta, (OLAX. UW Testaceita.. 12 Fitrina. 13 Helios. . (4 Carceclla SSAPRCSICTIOR /0 Belicina. |i Pupa. (8 Clausitia /9 Puli. 20-Achalina 2 Succtnea. 22eduricutad 23 Cyclestonmia. 24 Ltan0orbes. 23 Physa. 26Lymnecs 27 Uelaria LEMel71gescs. 29 arena. 30 Vatvata. 3) Faludina P2LAmpularia. BNWeritina. 34.WVavicella. BF Nérita: PS Duval, Lith? Frit 2 1Nivizca. 2 Janthina3s, wyarelus.4S5tomualela. 5 Stomatia. OHaliatis 7 Lornateile. SLlyra merdelli. 9 Véerrmetius. /OScalarin. I Debphinula. 12 Solarium. /3 Rotetia. 14 Treeias. (iMonodonta, l¢ Turbec. (7 Poeanaxis. /S Phastanelia./9Turritella. 20 Cerethiune. 2/ Pleurotomea. 22 Turbinetia. 23 Cancillaria 24 Fascwlaria. 25 Fists. 26Ly7uUla, 27 Strethiolarcn. £3 Ranella. 29 Murex. x0 Triton. 3/ Rostellaria . FE. S. Duvat, Lith? Pel. CronbUud. 3 CAAA. 4 CASSIS. & Ltctnula. oe / Steroceras. 2 6 Furprera. 7Monceeres. 8 Concholepas. 9Harpa. 10 Dolium: MI Duccrwnure, (2 Bburna. 13 Terebra. I Colum bctiai 5 Mitra. lo liluta 1) Marginelia, (8 Veivaria. 19 Cvila. 20 Gypree. 2l Terebellum. 22Ancillaria. 23 blivaz 26. Conds. LIS pir Uda 26 Mietilus. 2iArgonauta. 28 Carinaria. EP. S.Duvai, Lith? Phil” ¥ = dl . my - . < fy > aa ‘ Pap ‘ 4 7% 5 > om ‘ “ aX * , ~ EXPLANATION OF THE PSEES OF Pier . MULTIVALVE. ea ~ : . Murtrvatve shell is composed of more parts than two. ' Every part of a shell which is connected by a cartilage, ligament, hinge, or tooth, is called a valve of such shell; thus the Chitons have eight transverse, broad, but very short valves, placed on the back of the animal, and inserted at their sides into a marginal tough ligament. Plate I. fig. 1LAASA. - Operculum consists of four small valves on the. amit of the lepas, which shut up the superior orifice ; it is in a certain degree stationary, and different from the operculum of univalve shells, which will hereafter be described. Plate I. fig. 1. a. Fig. 9. re- presents a profile view of the operculum removed from its place, Al the front valves, B the back valves. Fig. 10, a front view of - the operculum. r P Base, is that part of the shell by which it is fixed to rocks and other bodies. Plate I. fig. 1. and 2. 8 B B.—mnis a piece of, stone *: to which the base is fixed, and « a piece of wood to which the shells of this section are generally attached. Ligament, is the membranous or tendinous substance by which the valves or parts of the shell are attached. Some multivalve shells are connected by the parts of one valve locking into an other. Plate I. fig. 2.p pv pv. The ligaments vary considerably in their texture, being scaly, prickly, smooth, or punctated. k Ridges, are certain convexities in many of the Lepas tribe, sometimes longitudinal and sometimes transverse. Plate I. fig. 1. F F. Peduncle. A sort of stem by which the shells of the Anatifera are attached to wood, &c. It is a membranaceous substance, similar to a bladder but materially thinner, and filled with a liquid which evidently affords nourishment to the animal. Plate I. fig. 2. c, the peduncle is usually affixed to a piece of wood as represented at &. > P) * 6 INTRODUCTION. Feelers, are those crenated arms, evolved from the side of the Anatifera. While the animal is in the water it continually moves its feelers, evidently for the purpose of entangling minute marine insects, as food. Plate I. fig. 2. » x. Accessory Valves, are small plates which cover the apex at the hinge of the Pholades, or are situated below the hinge. Plate I. fig. 3. 7. argin.—A fleshy border in which the valves are attached in the genus Chiton. Plate I. fig. 11. B B. BIVALVE. a Bivalve shells consist of two parts or valves, connected by 2 eartilage, and a hinge which is generally composed of teeth ; those of the one valve locking into a cavity in the other. The valves of some bivalve shells are formed exactly alike, and others are very different; the one being smooth, the other rugose ; one flat and another convex; and often one is shorter than the other. The shells of the Mya, Solen, Tellina, Venus, and others, have in general both valves alike, while those of the Spondylus, Ostrea, and Anomia, have in general dissimilar valves. The first of these kinds are called equivalve, and the latter inequivalve. Equilateral shells, are those whose sides are alike, as in the shells of the genus Pecten. Plate II. fig. 2. and plate VII. fig. 14. This is also exemplified in the Pectunclus. dInequilateral valves, are shells whose sides are unequal; and of different shapes, as in the Mactra, Donax, &c. Summit, is the most elevated point of that part of the shell in which the hinge is placed. Plate I. fig. 4. and 8. a a. In naming this the summit, we do not follow the axiom of Linneus, but because we consider it more properly the summit of the shell than the opposite extremity. Base, is the reverse of the above, or that part of the shell immediately opposite the summit. Plate I. fig 6. and 7. d d. Sides, the right and left parts of the valves. Plate I. fig. 6. . Posterior slope, is that part of the shell in which the ligament . EXPLANATION OF THE PARTS OF SHELLS. li is situated.. In viewing the posterior slope in front, the beaks of the shell retire from view. Plate I. fig. 4. i. Anterior slope, that part of the shell opposite the posterior slope; in viewing it in front, the beaks point to the observer. Plate I. fig. 4. k. : Disk, the convex centre of a valve, or most prominent part of the valve, suppose it with its inside lying undermost. Plate I. fig. 4. 0. Inside, the concave part of a valve. Plate IV. fig. 6.7. Muscular impression, is the impression left on the inside of the valves, by the adhering muscles of the animal. It differs in most shells, according to the shape of the animal, as semi-ovate, round, lunate, elongated, &c. As a specific distinction, it is often of great use; being, with a very few exceptions, alike in shells of the same species. Some shells have only one cicatrix, as the Edible Oyster, and Mytilus; others have two, and some few more; the Tellina forexample. Plate I. fig. 6. and 8. eeee. Lunule. The lunated depressions, situated in the anterior and posterior slopes. In different species of Venus they are prominent, characteristic marks, often of much service in ascer- taining a species. Plate I. fig. 4. 5 d. Ligament perforation. The circular aperture, or perforation through which the ligament passes ; by which the animal of the Anomia attaches itself to stones, and other marine extraneous bodies ; it is in general situated in the flat valve, though there are a few exceptions to the contrary. Plate I. fig. 7. m. Hinge, is the point at which bivalve shells are united, it is formed by the teeth of one valve inserting themselves between those of the other, or by the teeth of one valve fitting into the cavities or sockets of the opposite one. It is on the peculiar construction of the hinge that the generic character of bivalve shells is principally founded, together with the general contour of the shell. Plate II. fig. 1. and 3. ¢ qq. Teeth of the Hinge. Upon the number and relative situation of the teeth, principally depend the specific distinctions; they are of various forms, and very differently placed ; some are single and large, others numerous and small, orbicular, spatuliform, la- 4 12 INTRODUCTION. minated, &c. Some hinges have no visible teeth, and are termed inarticulate——W hen a primary tooth has a- groove or hollow in its centre, it is called complicated. Plate IV. Fig. 6.e; those with few teeth are termed articulate. Plate IV. fig. 1. and 12. and those with many teeth muitiarticulate. Plate IV. fig. 2. 3. 4,&c. Platel. fig. 6.and8 ee 98. Primary teeth, are those teeth in general situated in the cen- tre of the hinge, and are for the most part broad, large, and dis- tinct, often elevated; and in’ general are inserted in a cavity in the opposite valve. They however differ very much in some shells, but may easily be distinguished. Plate IV. fig. 1, 3, and 7.aaaaa. These are also termed the Cardinal Teeth. Lateral Teeth, Plate IV. fig. 10. are teeth which diverge from the umbo, and are in general long and flat, often double and di- vided by a groove or hollow. Plate IV. fig. 2, 4, 6, and 7. bbb ob. Double Teeth, Plate IV.