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

compressa. L. piperata. L. tellinoides. 2. Genus Mactra. Animal. Body oval and pretty thick; edges of the mantle thick, smooth, or without tentacular papille, augmented behind by two indistinct tubes ; mouth small and oval ; labial appendages narrow ; branchial lamine very small, and united in their length among themselves and with those of the opposite side ; foot oval, trenchant, very long. Shell. The Mactra has a peculiar hinge distinguishing it from all other genera. It is triangular, with a curved or angular compressed tooth on each valve, with a small oblique cavity on each side, to which is attached the ligament. ‘Two lateral teeth, one near the primary tooth and one near the ligament. The shape of the shell is subtriangular or oblong ; exterior smooth, striated, or ribbed transversely ; two muscular impressions united by a narrow marginal tongue. Inhabits the British coasts. Thirty-four species. Mactra helvacea. M. grandis. M. stultorum. Mactra gigantea. M. spengleri. M. striatella. M. carinata. M. straminea. M. Australis. M. violacea. M. fasciata. M. turgida. M. plicataria. M. rutescens. M. maculata. M. subplicata. M. triangularis. M. maculosa. M. ovalina. M. alba. M. solida. M. castanea. M. rufa. M. squalida. M. brasiliana. M. donacina. M. depressa. M. lilacea. CONCHOLOGY. Al -M. lactea. M. trigonella. ~ M. abbreviata. M. deltoides. M. crassatella. M. alata. 3. Genus Crassatella. Animal. Unknown. Shell. Close, suborbicular or transverse, striated longitudi- nally, denticulated, regular, equivalve, inequilateral, summits well marked, and turned to the front: primary-teeth somewhat divergent with a hollow at the side; no lateral teeth nor obsolete ones; ligament internal and inserted into a pit in the hinge, It is easily known from the Mactra and Lutraria by the valves fitting exactly. The living species of this genus only exist in the seas of Australasia, while in a fossil state we find at least seven species in France. Eleven species. Crassatella kingicola. Crassatella subradiata. C. donacina. C. contraria. C. sulcata. C. cuneata. C. rostrata. > C. Erycinea. €. glabrata. C. cycladea, C. striata. 4, Genus Erycine. Animal. Unknown. Shell. Somewhat longer than high, subtrigonal, regular equi- ' valved, inequilateral, gaping but little or not at all ; sumits well marked and a little inclined to the front; hinge subsimilar; two unequal cardinal teeth converging to the summit; two oblong compressed, short, and inserted lateral teeth ; ligament interna and situated in a pit. Owing to the equivocal character of this genus it is somewhat difficult to judge of the hinge. Inhabits the Indian Ocean. One species. Erycina cardioides. 5. Genus Ungulina. Animal, Unknown. Shell. Vertical or sublongitudinal, a little irregular, not gaping, 5* ‘e 42 CONCHOLOGY. equivalve, subequilateral, with summits a little marked; hinge dorsal, formed by a cardinal tooth; two long muscular impres- sions, one short primary cleft tooth in each valve, with an oblong groove divided in the middle of the margin, ligament internal, inserted in a pit. Two species. Ungulina oblonga. Ungulina transversa. 6. Genus Solemya. Animal. Unknown. Shell. Covered with a thick epidermis, enclosing it entirely except at the extremities, regular, somewhat thick, oval, elongated, straight and parallel edges, also rounded at its two extremities, valves equal, very inequilateral; the anterior side much longer than the posterior; summits feebly marked; hinge subsimilar, formed by a cardinal tooth, dilated, compressed, and a little reflexed above ; subexterior ligament inserted upon the tooth, and nearly at the posterior extremity of the shell; two small, rounded, widely separated muscular impressions, without any visible abdominal impression. Two species. Solemya australis. Solemya mediterranea. 7. Genus Amphidesma. Animal. Very imperfectly known. Shell. Transverse, inequilateral, somewhat rounded or sub- oval; sides slightly gaping; hinge with one or two cardinal teeth, and a narrow groove for the internal ligament ; ligament double, the external one short, the internal one fixed in the internal grooves. The two ligaments distinguish this genus from ail other bivalves. Inhabits the West Indian seas. Thirty-six species. Amphidesma variegatum. Amphidesma Tenuii. A. donacillum. A. purpurescens. A. lacteum. A. nucleolum, A. corneum. A. physioides. A. albellum. A. pulchrum. A. flexuosum. A. pallidum. A. prismaticum. . A. formosum. A. phaseolinum. A, roseum,. A. corbuloides. A. ellipticum, CONCHOLOGY. 43 A. glabrellum. A. subtruncatum. A. lucinale. A. solidum. A. Boysii. A. cordiforme. A. lenticulare. A. rupium. A. cancellatum. A. lamellosum. A. reticulatum. A. crenulatum. A. duplicatum. A. punctatum. A. leve. A. multicostatum. A. prismaticum. A. siculum. FAMILY VI. Corspuiacea. Two genera. 1. Genus Corbula. Animal. Unknown. Shell. Tolerably solid, regular, inequivalve, inequilateral with a conical, flexed, ascending, primary tooth in each valve; a cavity at the side ; no lateral teeth ; ligament interior. placed in the cavi- ties; two neighbouring muscular impressions. Inhabits the British seas. Nine species. Four fossil. Corbula australis. Corbula taitensis. C. sulcata. C. nucleus. C. erythrodon. C. impressa. C. ovalina. C. porcina. C, semen. 2. Genus Pandora. Animal. Body much compressed, somewhat elongated, in form of a furrow, in consequence of the union of the edges of the mantle, and its continuation with the tubes, which are united and short ; foot small, thickest in front, and issuing through a tolerably large cleft in the mantle. Shell. Regular, white, elongated, much compressed, inequi- valved, inequilateral; right or upper valve quite flat, with a fold; summits feebly marked ; hinge anomalous, formed by a transverse cardinal tooth on the right ; valve entering a corresponding cavity 44 CONCHOLOGY. in the left; ligament internal, oblique, triangular, inserted in a somewhat deep pit, with edges a little projecting on each valve ; two round muscular impressions. Inhabits the Mediterranean and British seas. Two living species, and two fossils, according to _ Defrance. Pandora rostrata. Pandora obtusa. FAMILY VII. Lirnoruacr. Three genera. 1. Genus Saxicava. Animal. Long, subcylindrical, the mantle closed in all parts, prolonged behind by two long tubes, thick and close together externally, pierced interiorly and in front with a round orifice, for the passage of a very smail foot; mouth very large; labial appen- 4 _dages small; branchial lamine free, the external pair much shorter - than the internal. Shell. Thick, with an epidermis, a little irregular, elongated, subcylindrical, obtuse at both ends; summits feebly marked ; hinge toothless, or with a very small rudimentary tooth ; ligament external, somewhat inflated; two round muscular impressions, distinct, and several others, irregular. Inhabitsthe British seas, and cavities which they bore in rocks or wood. Five species. Saxicava Rugosa. Saxicava pholadis. S. gallicana. S. australis. S. veneriformis. * * 2. Genus Petriceta. Animal. Unknown. Shell. Subtrigonal, more or less irregular, transverse, inequi- lateral; upper side narrowed and a little gaping; lower side rounded; hinge with two teeth. in each valve, or in one valve only. Inhabits the Australian seas, boring into wood and rocks. Thirteen species. Petricola lamellosa. Petricola rocellaria. P. Ochrolenca. P. exilis. P. Semilamellata. P, ruperella. CONCHOLOGY. 45 P. Jucinalis. P. chamoides. P. striata. P. pholadiformis. P. costellata. P, labagella. P. linquatula. 3. Genus Venerirupis. Animal. Unknown, but probably resembling the Venus. Shell. Transverse, inequilateral, posterior side short, the anterior gaping slightly. Hinge with two teeth on the right valve, three on the left, and sometimes three on both—these are small, near together and parallel. Ligament exterior. Inhabits the British seas, boring into rocks and clay. Eight species. Venerirupis perforans Venerirupis exotica. V. nuclea. _ V. distans. V. Ira. ¥. crenata. V. carditoides, V. alata. FAMILY VIII. Nympnacea. Ten genera. This family is divided into N. Solenaria and N. Tellinaria, from their resemblance to the Solen and Tellina. N. Sorenarra. Three genera, 1. Genus Sanguinolaria. Animal. Unknown. Shell. Oval, compressed, a little elongated, gaping but little, equivalve, subequilateral, rounded at both extremities ; no mark of posterior keel; summits feebly marked; hinge formed by one or two contiguous cardinal teeth upon each valve; ligament pro- jecting ; two round muscular impressions, distant and joined by a narrow palleal impression strongly sinuous behind. Inhabits the sea at Jamaica. Five species. Sanguinolaria occidens. Sanguinclaria livida. S. rosea. S. rugosa. S. alba. tip” 46 CONCHOLOGY. 2. Genus Psammobia. Animal. Unknown. Shell. Transverse, oblong-ovate, or elliptical, flattened, slightly gaping at one side; summits projecting; hinge formed by two primary teeth in the left valve, and one in the opposite one. Inhabits the European seas. Eighteen species. Psammobia virgata. Psammobia alba. P. ferroensis. P. cayennensis. P. vespertina. P. levigata. P. florida, P. tellinella. P. muculosa. P. pulchella. P. cerulescens. P. aurantia. P. elongata. P. fragilis. P. flavicans. P. livida. P. sqamosa. P. galathea. 3. Genus ‘Psammotea. Animal. Unknown. Shell. Of the same form as the Psammobia, but differing in the number of teeth, the left valve of the Psammotea having only one tooth; and sometimes one valve is without teeth, while the other has two; ligament exterior, attached to callosities at the hinge, and without an irregular plait. Inhabits the Australian seas. Seven species. One fossil species. Psammotea violacea. Psammotea candida. P. zonalis. P. tarentina. P. pellucida. P. donacina. P, serotina. N. Terirrina. Seven Genera. The two last of these genera have no lateral teeth, the rest have one or two. 4. Genus Tellina. Animal. Body triangular, much compressed ; the free edge of the mantle furnished with a row of tentacular largest and longest in the rear ; foot very large, compressed and pointed to the front ; buccal appendages nearly as large as the bronchial lamine, of CONCHOLOGY. 47 which the external pair are much smaller than the internal; the anterior contractile muscle larger than the other; tubes very distinct. Shell. Of a somewhat variable form, generally striated longi- tudinally and much compressed, equivalved, more or less inequi- lateral ; the anterior side almost always longer and more rounded than the posterior, which constantly presents a flexuous fold, at least at its inferior edge ; summits feebly marked ; hinge similar, one or two cardinal teeth ; two lateral teeth, far apart with a pit at their base in each valve; ligament posterior, large; round muscular impressions. The finest species of this beautiful shell are found in the pearl fisheries of Ceylon. Fifty-five species. Tellina unimaculata. Tellina margaritina. T. virgata. T. semizonalis. T. staurella. T. lutirostra. T.. rostrata. T. spengleri. T. radiata. . crucigera, . elliptica. . albinella. rosea. foliacea. operculata. . remies. sulcata. crassa. HHH HSS esas exilis. donacina. nitida. . striatula. . decussata. obliqua. - nymphalis, S4H5445 . chloraleuca. T. strigosa. T. planata. T.. punicea. T. depressa. T. pulchella. T. fabula. T. tenuis. T. sulphurea. T. cornuta. T. irrisa. T. levigata. T. linquafelis. T. rugosa. T. lacunosa. T. gargadia. T. pristis. T.