ball: mollusca and brachiopoda. 265 



Drillia decenna Dall, n. sp. 



Shell small, while, solid, acute, with al)out eight whorls, the spire longer than 

 the aperture ; the two nuclear whorls are small, smooth and apicallj blunt, the 

 succeeding ones have strong axial sculpture, but visible spiral sculpture is con- 

 fined to the region of the canal ; suture appressed, the anal fasciole inconspicuous ; 

 axial sculpture of (on the last whorl 8-10) sharp, slightly protr^ctive ribs, most 

 prominent on the periphery, the last rib preceding the formation of the adult 

 aperture distinctly larger than the rest ; the ribs thougli not invariably continuous 

 form a series obliquely ascending the spire, and in front fading out only near the 

 canal where there are a few spiral threads ; on the surface when not worn, can 

 be discerned with a lens fine spiral striations, but whether these are generally dis- 

 tributed my material is not fresh enough to show; aperturo short, rather wide; 

 anal sulcus shoi't, conspicuous, witli projecting margin ; outer lip slightly vari- 

 cose, sharp, produced; pillar smooth, short, straight, heavily callous; canal short, 

 rather wide, the fasciole inconspicuous. Length, 12.5 ; of last whorl, 8.0 ; of 

 aperture, 5.5 ; max. diam. 5.3 mm. 



U. S. S. " Albatross," station, 2798, in 18 fathoms, sand, Panama Bay. U. S. N. 

 Mus. 110,603. 



This species is related to Z>. ebur, D. coccinata and D.fucata of Reeve, of the 

 West Indies, but has fewer and less knobby ribs than any of them. 



Gemmula exulans Dall. 



Plate 13, figure 5. 



Pleurotoma exulans Dall, Proc. U. S. Nat. Mus., 1889, 12, p. 802, pi. 5, fig. 7. 



U. S. S. " Albatross," station 3370, off the coast of Ecuador, in 1132 fathoms, 

 ooze, bottom temperature 36° ¥. U. S. N. Mus. 123,095. 



An immature specimen of tliis species was obtained at the locality mentioned. 

 The original specimens were obtained near the Galapagos Islands at stations 2807, 

 in 812 fathoms, ooze, and 2808, in 634 fathoms, sand; temperatures 38°.4 and 

 40° F. 



Gemmula esuriens Dall, n. sp. 



Shell small, solid, subfusil'orm, of about five whorls, (he nucleus defective; 

 periostracum pale olive ; suture distinct, not appressed ; fasciole hardly constricted ; 

 whorls moderately rounded, the suture between them not deep; axial sculpture 

 of incremental lines and about twelve peripheral rounded low noduK's, hardly pro- 

 duced enough to be termed ribs; spiral sculpture in front of the periphery of l.i- 

 20 incised, ratlier distant, obscure lines extending to the cannl ; none is visible 

 behind the periphery where the sculpture consists chiefly of incremental lines and 

 faint traces of vermieulation ; aperture lunate; anal sulcus wide, shallow; outer 



