416 A. E. Yerrill — 3follusca of the New England Coast. 



ones ; some of the smaller cinguli are also found on the subsutural 

 band. The transverse sculpture consists of fine, slightly flexuous 

 lines of growth, crossing both the cinguli and their intervals, and on 

 the subsutural band becoming more prominent in the form of oblique, 

 recurved riblets, which do not take the form of nodules. On the last 

 whorl the revolving; cinauli continue at about uniform distances over 

 the entire whorl and canal, but anteriorly the cinguli thicken and are 

 wider than the grooves, while on the convex part of the whorl they 

 are narrower than the intervals. 



The aperture is broad-ovate, rather large, acute posteriorly ; the 

 outer lip is thin, strongly convex in the middle, with a broad and 

 shallow posterior sinus above the shoulder. The canal is short, 

 straight, not contracted at the base. The columella is straight in the 

 middle, with an oblique anterior edge; the inner margin of the aper- 

 ture is strongly excavated and subangular at the base of the colu- 

 mella. Umbilicus none. The animal is destitute of an operculum. 



The nuclear whorls are deep chestnut-brown, very minutely reticu- 

 lated by oblique lines running in two directions. The whorls are 

 regularly convex, the apical ones minute and a little prominent, so 

 that the apex is acute. 



Color of the shell below the brown nucleus translucent bluish 

 white, with a somewhat glossy surface; when dead, yellowish white. 



Length of the type-specimen, 11'^™; breadth, 7™'"; length of body- 

 whorl and canal, 7-5™"' ; length of aperture, 6'"'" ; its breadth, 2-8™'°. 

 Another somewhat larger and stouter specimen is 11*5™™ long; 

 breadth, 7'5""" ; length of body-whorl and canal, 8™"; length of aper- 

 ture, 6-3"'"'; its breadth, 3-8™"\ 



Station 2,221, N. lat, 39° 05' 30", W. long. 70* 44' 30", in 1,525 

 fathoms; two specimens (No. 40,498). 



This shell bears little resemblance to any of our other species 

 except P. Hrwieri. It differs froni the latter in having a higher and 

 more acute spire, with the whorls less strongly shouldered and the 

 subsutural band mtich less convex; the canal is shorter; the aperture 

 relatively broader, and the inner margin more excavated at the base 

 of the columella; the spiral cinguli are fewer, stronger, more promi- 

 nent, and more sharply cut ; the transverse lines are less strongly 

 recurved in crossing the subsutural band, but become more promi- 

 nent close to the suture; tlie posterior sinus of the lip is much shal- 

 lower and less distinct; the nucleus is similar in the two forms, but 

 is a little more acute in the present species. From all the other 

 species it differs so widely that no detailed comparison is necessary. 



