60 BULLETIN OF THE 



ular and extend partially over the notch-band, which is thus rendered much 

 less conspicuous than in the last species ; the notch is also less marked and 

 the spire has a stouter aspect. Lon. of shell, 5.75 ; of last whorl, 4.25 ; of 

 aperture, 3.0. Lat. of last whorl, 2.5 mm. Detl. about 41° 

 Cape San Antonio, 640 fms. 



P. (Mangilia) Pourtalesii n. s. 



Shell slender, dull, light brown, eight-whorled ; nucleus large, bubble- 

 shaped, smooth, forming a blunt apex ; other whorls furnished with numerous 

 (on the whorl next to the last 20, and on the last 27) narrow, little-raiseil, 

 rounded riblets with somewhat wider interspaces, becoming less distinct and 

 more crowded in the adult near the aperture ; the posterior terminations of 

 these riblets are waved, forming an obscure notch-band, each being slightly 

 enlarged close by the suture and also on the anterior side of the band, thus 

 forming two rows of indistinct nodulations, of which the sutural row is more 

 clearly defined than the other ; the riblets extend from suture to suture, and 

 near its anterior third become obsolete on the last whorl ; here eight or ten 

 rather indistinct revolving threads exist, becoming more distinct toward the 

 end of the canal, separated from eacli other Ijy shallow grooves ; these pass 

 round the column into the aperture ; canal short, wide ; aperture simple, with 

 thin margins ; notch rather indistinct in the adult. Lon. of shell, 17.0 ; of 

 last whorl, 9.5 ; of aperture, 7.0. Lat. of last whorl, 6.0 ; of aperture, 2.0 mm. 

 Defl. about 25=. 



Bed of the Gulf Stream, Pourtales, in 447 fms. 



An inconspicuous but well-marked species. 



P. (Mangilia) columbella n. s. 



Shell whitish, inclining to dove-color, slightly translucent, thin, delicate, 

 with eight and a half sub-turreted whorls ; nucleus minute, shining, glassy, 

 transparent ; succeeding whorls regularly sculptured by transverse slightly 

 oblique riblets, about twenty on the last whorl but one, extending from suture 

 to suture on the spire, somewhat shouldered before the suture giving the spire 

 a sub-turreted appearance, becoming less numerous, regular and prominent on 

 the last whorl, and vanishing at or before reaching its periphery ; revolving 

 sculpture of close microscopic striae often elegantly waved, covering the whole 

 surface except the apical whorls ; column short, straight, simple, with a groove 

 behind it, forming a distinct siphonal fasciole ; notch very shallow and incon- 

 spicuous ; outer margin thin, simple ; canal very short and wide ; aperture 

 almost lunate. Lon. of shell, 10.0 ; of last whorl, 6.5 ; of aperture, 4.5. Lat. 

 of shell, 4.5 ; of aperture, 1.8 mm. Defl. about 36°. 



Station 20, 220 fms. 



This is one of the species which, in the absence of the soft parts, is difficult 

 to locate. It is possible it should be referred to Bela. It is not unlike one or 

 two Arctic species. 



