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Show 120 DR. G W Y N JEFFREYS ON THE MOLLUSCA OF THE [Feb. 19, 24. RISSOA NANA, Philippi. B. pusilla, Ph. Moll. Sic. i. p. 154, t. x. f. 13. R. nana, Id. op. cit. ii. p. 127. 'Porcupine' Exp. 1870 : Med. St. 55, Adventure Bank. Distribution. Coasts of Western France, the Mediterranean and Adriatic ; 30-777 fms. Fossil. Miocene : Madeira. Pliocene : Monte Mario and Calabria. Post-tertiary: Rhodes. The reason given by Philippi for changing the name which he originally proposed, viz. because Broccbi had previously given the name pusillus to a species of Turbo, was not satisfactory, inasmuch as Brocchi's shell belonged to Rissoina and not to Rissoa. This I have ascertained by an examination of Brocchi's specimens. But the change has been sanctioned and adopted by modern con-chologists. Not R. nana of Grateloup, which is a Miocene species of the Bordeaux Basin, nor R. nana (Partsch), Homes, from the Vienna Basin, both names being subsequent in date to that of Philippi. I greatly doubt the identification of the present species with R. dolium of Nyst, which name was substituted by him for B. pusilla of Marcel de Serres, also a fossil of the Bordeaux Basin. Possibly our species may be the B. pulchra of Forbes ; but the size which he gives (one tenth of an inch) is far too great. Unfortunately the iEgean shells were dispersed, and many of them lost to science; his descriptions, or rather notices, were too short and insufficient for the exact comparison of his species, and very few of them were figured. 25. RISSOA TURRICULA l, Jeffreys. (Plate IX. fig. 6.) S H E L L turreted, thin, semitransparent, and somewhat glossy: sculpture, 20-25 slight and gently curved longitudinal ribs on the last whorl, and nearly as many, but finer, on the next whorl; the remainder of the shell is smooth ; there are no spiral striae or other markings: colour whitish : spire pointed: whorls 4, swollen, gradually increasing in size ; apex slightly twisted on one side : suture deeply excavated : mouth roundish : outer lip sharp ; inside smooth : inner lip reflected on the lower part of the pillar, behind which is a small chink. L. 0*05. B. 0*035. ' Porcupine' Exp. 1870: Atl. St. 3. Two specimens, not in good condition. I propose this species with some hesitation, because the specimens have the appearance of being decorticated, like casts of a fossil shell; but I cannot identify them with any known species. 26. RISSOA INCONSPICUA, Alder. R. inconspicua, Aid. in Ann. & Mag. N. H . xiii. p. 223, pi. viii. f. 6, 7 : B. C. iv. p. 26 ; v. p. 207, pi. lxvii. f. 5. 'Porcupine ' Exp. 1869 : St. Donegal, B. 1870 : Atl. Vigo B., 24, 26-30, 35, Tangier B.: Med. 50, Adventure Bank. A little bower. |