49 



numerous close growth striae, also visible on the ribs. Apex with a wide deep slit totally cutting 



away the convex side of the apex over a varying distance of 0.5 to 1,5 mill. 



Martin on the convex side thin-edged on the concave side thick-edged. Anterior 



aperture keeled on the inner and narrowly arched on the outer margin, not oblique. 



a. Length 21,5 mill., diameter of apert. 2,5 X 1,6 mill. j,.^ , 



è. Length 19 mill.. diameter of apert. 2,2 X lö mill. .\nterior aperture 



c. Length 15 mill., diameter of apert. 2,2 X i-5 niill. 



First is given the antero-posterior, then the lateral diameter, measured between the 

 lateral keels. 



Remarks. This form brings a second species into the subgenus Bathoxiphus. The only 

 hitherto known species of that subgenus, D. ensicubcs Jeffreys is distributed over the eastern 

 and western Atlantic, Gulf of Mexico and the West-hidies. Both species are nearly allied, but 

 t)'icarinat7ii)i is shorter and more curved, has two prominent lateral keels and the slit is less 

 long than in citsiculiis. 



Subgenus Gadilina F'oresti 1895. 



1895. Gadilina Foresti, Buil. della Soc. Mal. Italiana XIX, p. 259. 



1897. Gadilina Foresti. Sacco, I MoUuschi del Piemonte e della Liguria, Parte XXII, p. 113. 



1897. Gadilina Foresti. PiLSBRY & Sharp, Man. of Conch., vol. XVII, p. xxxii. 



Shell smooth and slender, triangular or faintly triangular in section ; the concave side 

 flattened, the convex side rounded. Type D. triqtietriiDi Brocchi. 



This group was ranked as a subgenus of Siphonodentali?i >ii , but examination of the living 

 animal brought to light that it belongs to the Dentalidae, the foot having the regular epodial 

 sheath of species belonging to that family. 



K e y t o Species. 



l. Shell decidedly trigonal. 



a. The angles strongly accentuated stapes. 



a' . The angles more rounded msolitum. 



IL Shell cylindrical or faintly trigonal. , 



a. Shell very slender and attenuated pachypleuricm. 



a . Apex strongly truncated trnncatum. 



58. Dentali2nn insolitum E. A. Smith. PI. V, fig. 15. PI. \T, figs 80, 82, 84. 



1894. DentaliuiiL tnsolitum E. A. Smith, Ann. Mag. Nat. Hist. (6) XIV, p. 168, pi. 4, fig. 17, \'ja. 

 1897. Dcntaliuiii insclitum E. A. Smith. PiLSBRY & Sharp, Man. of Conch., vol. XVII, p. 109, 



pi. 22, figs 56, 57. 



Stat. 45. 7°24'S., 118° 15.2 E. Flores Sea. 794 Metres. Fine grey mud, with some Radiolariae 



and diatomes. i Spec. 

 Stat. 52. 9° 3'.4 S., 119° 56'. 7 E. Sumba Sea. 959 Metres. Globigerina ooze. 3 Spec. 



smOGA-EXPEDITIE LIV. 7 



