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Show 1884.] 'LIGHTNING'AND ' P O R C U P I N E ' EXPEDITIONS. 361 44. ODOSTOMIA PAUCISTRIATA1, Jeffreys. (Plate XXVII. fig. 6.) S H E L L forming an elongated cone, rather thick, semitransparent, and of a prismatic lustre: sculpture, straight, slight, and irregular longitudinal ribs, about 20 on the last whorl, but varying in number, extension, and size : colour white : spire produced, aud somewhat abruptly tapering : suture rather deep, nearly straight: whorls 8 besides the nucleus, moderately convex but not tumid ; the last occupies two fifths of the spire ; nucleus twisted outwards : mouth pear-shaped, pointed above and rounded below: outer lip thin : inner lip thickened : base angulated in the young. L. 0*275. B. 0*085. 'Porcupine'Exp. 1870: Med. St. Benzert Road. Four specimens of different sizes. Distribution. Bay of Biscay (' Travailleur' Exp. 1880 and 1881), Palermo and S. Vito (Monterosato), off west coast of Africa (' Talisman ' Exp.), off Culebra, Danish W . Indies (' Challenger' Exp.) ; 108-681 fms. Fossil. Pliocene : Messina (Seguenza), Altavilla (Monterosato) ! Although this appears to differ from O. compressa in being conical instead of cylindrical, as well as in the less compression of the whorls and the irregularity of the sculpture, I am not satisfied that they are distinct species. I therefore give both provisionally. Two specimens of the present species have a rather strong tooth-like fold on the inside of the pillar. 45. ODOSTOMIA SEMICOSTATA2, Jeffreys. (Plate XXVII. fig. 7.) S H E L L cylindrical, rather thick, semitransparent and glossy : sculpture, a few slight longitudinal ribs, sometimes covering the top whorls only, but in most specimens disposed irregularly over the shell; in one specimen the whole of the surface is seen under the microscope to be finely striated in a spiral or transverse direction: colour white : spire elongated and ending somewhat abruptly in the nuclear point: whorls 8 besides the nucleus ; they are rounded but not convex, and are compressed in the middle ; the last occupies about one third of the spire ; nucleus bulbous and regularly spiral, like all other species of this genus : suture narrow : mouth trapezoid : outer Up inflected and pointed above, contracted in the middle, and curved below: inner lip thickened: base somewhat angulated, particularly in the young : pillar nearly straight: tooth or columellar fold sunken but conspicuous in a broken specimen. L. 0*15. B. 0*035. 'Porcupine' Exp. 1870: Atl. St. 26-30. Distribution. C. Breton, Gulf of Gascony (de Folin) ! D. Eulimella. Cylindrical, smooth, and toothless. 46. ODOSTOMIA SCILL^E, Scacchi, Melania scilla, Sc. Notizie int. aile Conch, p. 51, t. ii. f. 2. O. scilla, B. C. iv. p. 169 ; v. p. 213, pi. lxxvi. f. 5. 'Lightning' Exp. St. 2. i Having few ribs. 2 Half-ribbed. |