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Show 414 MOLLUSCA. a plate, and under the teeth a large cavity, which receives a part of the ligament( l ). GALATHJEA, Brug. The shell triangular; three teeth on the summit of one valve, and two on the other, en chevron; the lateral plates approximated(2). But a single species is known; it inhabits the fresh waters of the East Indies. It is here also that must be placed another genus separated from Venus, the Connis, Cuv.-FIMBRIA, Megerl. Marine testaceous Acephala, transversely oblong, which have also stout middle teeth, and well marked lateral plates; their external surface is furnished with transvet·se ribs so regular] y crossed by rays, that it may be compared to wicker-work. . The. impression of their mantle exhibiting no flexure, theit· tubes must bt. short(3). Some of them are fossil( 4). In the TELL IN A, Lin. There are in 'l\1e middle, one tooth on the left and two teeth on the right, frequent., forked, and at some distance before and behind, on the right val \e, a plate, which does not penetrate into a cavity of the opposite or'!. There is a slight plica near the posterior ex· tremity of the two "alves, which renders them unequal in that part, where they are some·rhat open. The animal of the Telince-PERONJEA, Poli,-like that of the Dona· ces, has two long tubes hr respiration and for the anus, which with· draw into the shell, and at, concealed in a duplicature of the mantle. Their shells are genera'y transversely striated, and decorated with beautiful colours. Some of them are oval and \ick. Others are oblong and strong'~' compressed. (1) Venus islandica, Chemn., VI, xxxii,'42, Encyc. pl. 301, f. 1; a large fossil species is found in the hills of Siennois and ~ar Dax, of Bourdeaux. (2) The Egeria, Roiss., or Galat!tma, llrug Encyc., 249, and Lam., Ann. du Mus., V, xxviii, and Venus hermaphroilita, Che~l., VI, xxxi, 327-329? Ol' Venit! 3Ubviridis, Gm. (3) Venusfimbriata, Chemn., VII, 43, 448. ( 4) See Deshayes, Coq. Foss. des Envir. de Par) I, xiv; Brongn., M6m. sur Je Vicentur. ACEPHALA TEST ACEA. 415 Some again are lenticular, where, instead of a plica, there is frequently nothing but a slight deviation of the transverse strire( 1 ). We might separate certain oblong species which have no lateral teeth(2), and others, which, with the hinge of the Tellince, have not the plica of the posterior extremity-they are the TELLINIDES, Lam.(3) It is necessary to distinguish from the Tellince, the LoRIPEs, Poli, In which the middle teeth of the lenticular shell are almost effaced, and where there is a simple sulcus for the ligament behind the nates. The animal is furnished with a short double tube, and its foot is prolonged into a kind of cylindrical cord. Besides the usual impressions, we may observe, on the inside of the shell, a line running obliquely from the print of the anterior muscle, which is very long, towards the nates. There is no flexure in the print of the mantle for the retractor muscle of the tube( 4). LuciNA, Brug. Separated lateral teeth, as in the Cardia, Cyclades, &c., that penetrate between the plates of the other valve; in the middle are two teeth, frequently, but slightly apparent. The shell is orbicular, and without any impression of the retractor muscle of the tube; that of the anterior constrictor, however, is very long. Possessing similar traits of character with the Lori pedes, their animals must be analogous( 5). The living species are much less numerous than those that are fossil; the latter are very common in the environs of Paris( 6). We should approximate to the Lucince, the UNGULINJE, which also have an orbicular shell and two cardinal teeth; the lateral ones, how- (1) These are the three divisions ofGmelin, but we must abstract from his genus Tellina: 1st. Tell. Knorrii, which is a polished Capsa; 2d. Tell. inrequivalvis, which is the genus Pandora,· 3d. Tell. cornea; T. lactMtris; 'F. amnica,· T. .ftuminali8; T.jluminea,· T. .ftuviatilis, which are Cyclades or Cyrena:. (2) Tell. hyalina, Chemn., VI, xi, 99;-Tell. vitrea, Jb., 101. (3) Tellinides timorensis, Lam. (4) Tellina lactea. (5} Venus pennsylvanica, Chemn., VII, xxxvii, 394-396, xxxix, 408, 409;-V. edentula, ld., xl, 427,429. (6) Lucina aaxlrrum, Lam., Deshayes, Coq. Foss. des Env. de Paris, I, pl. xv, f. 5, 6;-Luc. grata, Defr.; Ibid. pl. xvi, f. 5, 6;-Luc. concentrica, Lam., Desh., lb., xvi, f. 11, 12. |
