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Show 1871.] MR. T. DAVIDSON ON JAPANESE BRACHIOPODA. 309 come under my notice. It measured 8 lines in length by 7 in and 4 in depth. Hab. Gotto, 48 fathoms. Family RHYNCHONELLID_E, J. E. Gray. Genus RHYNCHONELLA, Fischer de Waldheim. The recent forms are few in number. Rh. psittacea, Gmelin, = var. woodwardi, Adams (?). Rh. nigricans, Sow., Rh. grayi, Wood ward, Rh. lucida, Gould, and Rh. sicula, Sequenza, MS., are all the species with which we are at present acquainted. RHYNCHONELLA PSITTACEA, Gmelin, var. WOODWARDI, A. Adams. (Plate XXXI. fig. 12.) Rh. woodwardi, A. Adams, Annals & Mag. of Nat. Hist. 3rd ser. vol.xi. p. 100, 1863. M. Adams states in his paper that "this species differs from Rh. psittacea in being concentrically striolate instead of radiately grooved; the beak, moreover, is smaller and less curved; the form is more broadly triangular, and the ventral margin rounded and produced in the middle. The young possess the same characters seen in the adult. Hab. Gotto, 48 fathoms; also off Rifunsiri Island, 4 miles from the shore, in 35 fathoms, from a bottom of coral, broken shells, and stones." I have been able to examine two examples of this shell, and could distinctly perceive faintly marked radiating striae, similar to those that cover the surface of __. psittacea. I cannot help thinking, and I am confirmed in this opinion by Mr. Jeffreys, that the R. woodwardi of Adams is no more than a local variety of R. psittacea. The colour of the two specimens obtained by Mr. Adams are of a less bluish tint than we find usually in the shell last named; but some examples of R. psittacea from the northern European seas have also assumed that colour. RHYNCHONELLA LUCIDA, Gould. (Plate XXXI. figs. 13, 14.) Rh. lucida, Gould, Proc. Bost. Soc. Nat. Hist. p. 323, 1860, and Otia Conch, p. 121; Adams, Annals and Mag. of Nat. Hist. 3rd ser. vol. xi. p. 100, 1863. Shell small, obtusely subrhomboidal or ovate, rather longer than wide; dorsal valve convex, almost gibbous; mesial fold wide, commencing to rise at about half the length of the valve. Ventral valve rather less convex or deep than the opposite one, and scooped out near the front in the form of a deepish sinus; beak acute, sharply incurved; foramen beneath the extremity of the beak, completed by a deltidium. Surface smooth, of a light whitish glassy grey ; shell-structure fibrous. Length 6, width 5, depth 3 lines. This very interesting species had never been completely described or illustrated. It was briefly noticed by Gould in 1860; but his observation that it might be taken for a small T. vitrea is quite in- |