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Show 54 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [Jan. 20, 'Porcupine'Exp. 1869: 23a. 1870 : Atl. 22. _ Distribution. North Atlantic ('Valorous' Exp.), Spitzbergen ('Voringen' Exp.), between the Faroes and Hebrides ('Triton' cruise) ; 400-1450 fms. C. danielsseni, Friele. G. procerum of Kiener is, according to Deshayes, a variety of G. fasciatum of Bruguiere. 3. CERITHIUM METULA, Loven. O. metula, Lov. Ind. Moll. Scand. p. 23 : B. C. iv. p. 256 ; v. p. 217, pi. lxx. f. 3. 'Lightning' Exp. St. 2, 5. 'Porcupine' Exp. 1869 : 23a, 42, 47,61, 65. 1870: Atl. 1, 2, 3, 6, 9, 16, 24-30. Distribution. Spitzbergen ('Voringen' Exp.), Finmark to Chris-tianiafiord and North Sea, Shetland, between the Faroes and Hebrides (' Knight Errant' and ' Triton' cruises), Fair Isle (Moller, f Mbrch), Bay of Biscay ('Travailleur' Exp.), Villafranca (Hanley); 20- 650 fms. C. nitidum, M c Andrew and Forbes. The number of the spiral ridges varies from 2 to 3 ; and the arrangement of the ridges is not uniform, being more compact or remote in some specimens than in others. The type of G. O. Sars's genus Lovenella. 4. CERITHIUM GRACILE1, Jeffreys. (Plate VI. figs. 3, 3 a.) S H E L L resembling C. metula in shape, but smaller and more slender, semitransparent, very glossy and of a prismatic lustre: sculpture, numerous curved longitudinal riblets, which are crossed by fine and thread-like spiral ridges ; of these last there are three on the last or body-whorl (viz. one below the periphery, the second or strongest encircling the periphery, and the third placed just below the suture) ; the ridges on each of the succeeding whorls are two in number, the larger being central, more prominent, and giving an angulated or keel-like appearance ; the base of the shell is quite smooth and somewhat concave ; the apex is also smooth ; the intercrossing of the longitudinal and spiral striae produces a few slight nodules in the middle of the shell, but not the tuberculated character of the last species : colour glossy white : spire tapering to a blunt point: whorls 12, rather convex, gradually enlarging; the last occupies one third of the spire with the mouth of the shell placed upwards ; the first or apical whorl is bulbous and obliquely twisted : suture defined more distinctly than in the other species : mouth irregularly rhombic, with a deep and wide groove at the base as in that species ; its length is about one fourth of the shell: outer lip thickish, indented or scalloped by the spiral ridges : inner lip filmy : pillar flexuous. L. 0-3, B. 0-075. 'Porcupine' Exp. 1870: Atl. St. 3. A single but perfect and living specimen. 1 Slender. |