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Show 302 MR. E. A. SMITH ON THE [Apr. 1, represent varieties and different stages of the same shell. The " Indian Ocean " given by Reeve to Am. cordiformis, which he assigns to Sowerby, is evidently incorrect. Say's species were from Georgia and E. Florida, A. reticulata, subtruncata, and decussata from the West Indies, A. lenticularis from West Colombia, and A. modesta from West Africa. The shells from St. Helena are only young specimens, 18 millim. in length, and agree with A. modesta as figured by Reeve (Conch. Icon. fig. 35 b). ERVILIA SUBCANCELLATA, Smith. Ervilia subcancellata, Smith, ' Challenger' Lamellibr. p. 80, pi. vi. figs. 2-2 b. Hab. West Indies; Fernando Noronha ; Brazil; 25-675 fathoms. The concentric sculpture is much coarser in some specimens than in others, and the radiating striae, as formerly pointed out, also vary. Young specimens, which are pellucid, exhibit on each side towards the end of the dorsal margin a small brown spot, also occasionally observable in more adult shells. CORBULA SWIFTIANA, C. B. Adams. Corbula swiftiana, C. B. Adams, Contrib. Conch, p. 236. Hab. Jamaica, St. Thomas, Hayti. CARDIUM (FRAGUM) SPECIOSUM, Adams & Reeve. Cardium speciosum, Adams & Reeve, Voy. 'Samarang,' p. 77, pi. xxii. fig. 9. Hab. China Sea (Ad. Sf Rve.). After a very careful comparison of the St. Helena specimens with the type of this species preserved in the British Museum, I have no hesitation in pronouncing them one and the same form. In shape and sculpture they are identical, but differ in having about three more ribs. The locality assigned to this species is possibly, or probably, erroneous, and I think it likely it may have been obtained at St. Helena on the voyage home, for, as stated by Mr. Adams in the preface to the 'Voyage,' p. vi, the ' Samarang' touched at St. Helena. Whether this species should or should not be regarded merely as a variety of the West-Indian C medium, Linne, I cannot now determine, not having a sufficient series of either for studying their variation or constancy. C. medium, however, has a less oblique form, and seems to be a broader shell, or, in other words, has a longer ventral margin, which is not so obliquely upsloping in front. The ribs, too, are usually flatter, and sculptured with much coarser curved striae. , ..'.. CARDIUM (PAPYRIDEA) BULLATUM, Chemnitz. Hab. West Indies, Brazil, and west coast of Central America. St. Vincent, Cape Verde Islands (Dunker). The synonymy of this species I have given in the Report of the |
