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Show 302 MR.T. DAVIOSON ON JAPANESE BRACHIOPODA. [Apr. 18, septum is elevated as in Magasella. Indeed I am not quite satisfied as to the genus Magas having been represented in the recent state, although T. patagonica of Gould has been doubtfully referred to it. Mr. Dall seems also inclined to separate Thecidium from the Tere-bratulidce ; but I do not feel convinced that he has clearly shown that Professors Suess, Deslongchamps, King, myself, and others have so much erred in considering the excavated lobes or crescents in the dorsal valve to be homologues of the loop. But that question may require further examination; and as no specimen of the genus has been hitherto obtained from the Japanese waters, I will defer the discussion to another occasion. Genus TEREBRATULA, Llhwyd. But very few recent species have been discovered. Terebratula vitrea, Born, T. minor, Philippi & Suess, T. spheeroidea, Phil., T. uva, Brod., and T. cubensis, Pourtales, have been referred to it; but it is still a question whether T. cubensis and T. minor are more than varieties of T. vitrea. A shell bearing great resemblance to the fossil T. spheeroidea of Philippi was also dredged by Messrs. Jeffreys and Kent near the coast of Portugal. Mr. Dall adds T. unguiculus (Cooper) to the recent species of the genus Terebratula; but I feel satisfied that Cooper's species will be more correctly placed in the genus or subgenus Terebratulina. From the Japanese waters we are acquainted with but a single species. TEREBRATULA MINOR, Philippi & Suess. (Plate XXX. figs. 10, 11, 12.) Terebratula vitrea, var. minor, Philippi, 1836. Terebratula affinis, Calcara, 1845. Terebratula davidsoni, A. Adams, Proc. Zool. Soc. p. 314, pl. 19. fig. 30, 1867. This shell has been well described by Mr. Adams in the ** Proceedings of the Zoological Society.' Mr. Jeffreys, however, is of opinion that the Japanese specimens cannot be distinguished from the pliocene and recent specimens known under the designation of T. minor or affinis ; and I must admit that Mr. Adams's two examples bear a good deal of resemblance to the European shell. Hab. Dredged by Mr. A. Adams at Satanomosaki in 55 fathoms. Subgenus TEREBRATULINA, D'Orb. I am inclined to consider this to be a subgenus of Terebratula, as the characters of its loop so nearly approach to those of the last-named genus. The number of recent species attributable to this subgenus has been considerably exaggerated, and several of them are no more than local variations or synonyms of the well-known and far spread T. caput-serpentis; T. japonica, T. septentrionalis, T. angusta, T. abyssicola, T. cancellata, T. cumingii, and one or two more seem referable to the Linnean species. Mr. Dall believes T. |