48 Smith and Harger — St. George's J^anks Dredgings. 



MOLLUSCA. 



Pleurotomella Packardii VerriU. 



American Journal of Science, III, vol. v, 1873, p. 15 (December, 1872). 



Shell thin, fragile, translucent, pale flesh-colored, moderately stout, 

 with an acute, somewhat turreted spire. Whorls nine ; the apical 

 whorls, for about two and one-half turns, are nearly smooth, regular, 

 convex, chestnut-colored ; below this the whorls are shouldered, strong- 

 ly convex in the middle, but with a smooth concave band below the 

 suture, corresponding to the posterior notch in the outer lip; the whorls 

 are crossed below the sub-sutural band by about 16 strong, prominent, 

 rounded, somewhat oblique ribs, most prominent on the middle of the 

 whorl, but not angulated ; on the last whorl these ribs become very 

 oblique below the middle, and follow the curve of the edge of the 

 lip, nearly fading out anteriorly ; the surface between the ribs is 

 marked by faint lines of growth and by fine, unequal, slightly raised 

 revolving lines, which pass over the ribs without intei-ruption. They 

 become more evident on the lower part of the last whorl, and are 

 very faint on the sub-sutural band, which is more decidedly marked 

 by receding, strongly curved lines of growth. The aperture is rather 

 broad above, elongated below, sub-oval, outer lip very thin, sharp, 

 prominent above, separated from the preceding whorl by a wide and 

 very deep sinus, extending back for about one-fifth of the circumfer- 

 ence of the whorl ; the anterior border of the lip is incurved near the 

 end, and obliquely truncate, forming a short, straight canal. Colu- 

 mella simple, nearly straight, its inner edge toward the end sharp, 

 and obliquely excurved. No operculum. Length, 21 •2""" ; breadth, 

 11-2'""'; length of aperture, 120™'"; breadth of same, 5-0""". The 

 absence of eyes and operculum, great size of the posterior sinus, and 

 character of the apex, indicate that this shell represents a new genus. 



One living specimen from (o) 110 fathoms. 



Ringicula nitida Verriii. 



American Journal of Science, III, vol. v, 1S73, p. 16 (December, 1872). 

 Plate I, figure 2, 



Shell small, white, smooth, broad oval, with five Avhorls, spire rap- 

 idly and regularly tapered, sub-acute, shorter than the aperture. 

 Whorls very convex, regularly rounded, the sutures well impressed ; 

 a well marked, impressed, revolving line just below the suture ; the 

 surface otherwise nearly smooth, but with more or less distinct, 

 distant, microscopic revolving lines, most distinct anteriorly. Aj^er 

 ture somewhat crescent-sha})ed. Outer lip evenly rounded, forming 



