1884.] 'lightning' AND 'porcupine ' EXPEDITIONS. 3G1 



^ 44. OoosTOMiA paucistriata', Jeffreys. (Plate XXVII. fig. 6.) 



Shell 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, and somewhat 

 abruptly tapering : suture rather deep, nearly straight : whorls 8 be- 

 sides the nucleus, moderately convex but not tumid ; the last occu- 

 pies two fifths of the spire ; nucleus twisted outwards : mouth pear- 

 shaped, pointed above and rounded below : outer Up thin ; inner 

 lip thickened : base angulated in the young. L. 0"275. B. O'OSo. 



'Porcupine' Exp. 1870: Med. St. Benzert Road. Four speci- 

 mens of different sizes. 



Distribution. Bay of Biscay (' Travailleur ' Exp. 1880 and 1881), 

 Palermo and S. Vito {Monterosato), off west coast of Africa (' Talis- 

 man ' 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. 



V 45. Odostomia semicostata^ Jeffreys. (Plate XXVII. fig. /.) 

 Shell 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 lip 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. O'lo. 

 B. 0-035. 



♦Porcupine' Exp. 1870: Atl. St. 2fi-30. 

 Distribution. C. Breton, Gulf of Gascony {de Folin) ! 



D. Eulimella. Cylindrical, smooth, and toothless. 



l/'^46. Odostomia scill.e, Scacchi. 



Melania scillce, Sc. Notizie int. alle Conch, p. 51, t. ii. f. 2. 

 0. scillce, B. C. iv. p. 169 ; v. p. 213, pi. Ixxvi. f. 5. 

 ' Lightning ' Exp. St. 2. 



1 Having few ribs. ' Half-ribbed. 



