MUSEUM OF COMPARATIVE ZOOLOGY. 59 



whoii eleven) lieconiing obsolete anteriorly, cand succeeded by a few (four or 

 fivej revolving riblets at the anterior extreme of the canal; suture appressed ; 

 lines of growth not evident ; whorls rather inflated in appearance ; notch very 

 slight ; aperture small and unusually short ; pillar very short, straight, and 

 pointed. Lon. of shell 4.5 ; of last whorl 2.25 ; of aperture, 1.25. Lat. of last 

 whorl, 1.75 mm. Detl. about 27°. 



Station 20, 220 fms. 



This very likely grows to larger size, and is notable for its peculiar translu- 

 cent wa.xy lustre. 



P. (Mangilia) bandella n. s. 



Shell thin, white, polislied, fusiform, eight-whorled ; nucleus smooth ; suc- 

 ceeding whorl or two scalariform, by reason of sharp scale-like transverse 

 lamella ; remaining whorls with sharp transverse ridges prominent on the 

 spire and on the posterior half of the last whorl (where there are eighteen of 

 them) and obsolete on the anterior half ; these ridges rise into points where 

 they cross the carina in front of the notch-band and the antci-sutural rib ; of 

 other transverse sculpture there are only the lines of growth which are promi- 

 nent only where they cross the band marking the track of the notch ; the re- 

 volving sculpture consists of a rather stout rib closely appressed to the suture 

 forming one margin of the band, the other edge of which forms a carina, in 

 advance of which are (on the last whorl 20 - 23) flattened riblets with aliout 

 equal interspaces which extend with regularity to the anterior end of the canal. 

 Aperture equal to half the total length, margins and column thin ; notch broad, 

 shallow, leaving a very distinct band ; spire moderately pointed. Lon. of shell, 

 9.37 ; of last whorl, 6.12 ; lat. of do., 3.75 mm. Defl. about 39°. 



Station 47, 321 fms. 



This has a superficial resemblance to the Bcia turricula group, which is less 

 evident on a closer inspection. It has the deep-water facies and (as will be 

 observed) the sutural band with raised sculpture common to so many other 

 abyssal species of totally difl"erent genera or even orders. 



P. (Mangilia) antonia n. s. 



This species at first siglit appears like a variety of the last, and is best 

 described by a differential diagnosis. It is six-whorled, with a length of 5.75 

 mm. ; the nucleus is clear brown instead of white, with three whorls, on most 

 of which there are scalar ridges which are much more closely and regularly set 

 than in the last, anil do not resemble lamellae ; there is only a trace of an ante- 

 sutural revolving rib in the earlier whorls which vani.shes entirely in the later 

 ones, and with it, of course, the tendency to raised points of sculpture ; tliough 

 its place is marked by a white opacity in the otherwise rather translucent 

 shell ; there are thirteen longitudinal ribs on the last whorl, which extend on 

 to the anterior fourth of the whorl instead of vanishing, and are more evident 

 and shariier where they cross the band ; while the revolving ribs are less reg- 



