238 A. E. Verrill — Molhisca of the New England Coast. 



tudinal ribs, wliicli run nearly straiglit across the whorls, and on the 

 last whorl extend to the base of the siphon ; these are separated by 

 deeply concave intervals of about the same width. The whole sur- 

 face is covered by strongly marked revolving cinguli, which cross 

 both the ribs and their interspaces, and thicken so as to form small, 

 rounded nodules where they cross the ribs ; these are separated by 

 interspaces of about the same width, in the middle of which there is 

 a much smaller, thin revolving cingulus, alternating pretty regularly 

 with the larger ones around the periphery. On the anterior part of 

 the body-whorl, and sometimes at the periphery, there are two or 

 three small revolving cinguli in some of the interspaces. On the 

 penultimate whorl there are usually five to seven of tlie primary cin- 

 guli, and on the body-whorl and siphon there are about eighteen to 

 twenty. The whole surface is also covered, in perfect specimens, 

 with fine, slightly elevated, wavy lines of growth, which are most 

 conspicuous on the intervals between the ribs; they are usually 

 worn off from the more prominent parts of the ribs and nodules. 

 The nucleus consists of about two and one half regularly coiled 

 Avhorls ; the first two are small, smooth, translucent and somewhat 

 lustrous; the last is covered with rather faint revolving lines, crossed 

 by the lines of growth, which gradually merge into the longitudinal 

 sculpture of the normal whorls, there being no very distinct demarca- 

 tion between the nucleus and the next whorl. The apical whorl is 

 minute, regularly increasing. Aperture elongated, ovate-fusiform; 

 outer lip thin, sharp, regularly curved; inner margin regularly 

 arched. Collumella somewhat elongated, its margin sinuous and 

 somewhat excurved at the tip. Canal narrow and somewhat elon- 

 gated, a little curved. Color bluish white. Epidermis very thin, 

 pale grayish or yellowish white. 



Length of one of the largest specimens, 15"""; breadth, V'"'" ; 

 length of aperture, 8"^"^ ; its breadth, 3""". 



This species was taken, off Cape Hatteras, at station 2109, in 142 

 fathoms, in considerable abundance (No. 35,735) ; station 2110, in 

 516 fathoms (one dead) ; and station 2111, in 938 fathoms, one living 

 (No. 35,764). Possibly the two latter specimens may be due to 

 accidental misplacement. 



This species bears considerable general resemblance to the shallow- 

 water species ( JJ. cmerea), but it is a much smaller and more slender 

 species, with a narrower aperture and longer canal. The sculpture 

 is more simple, there being usually but two sets of revolving cinguli, 

 the larger and smaller ones alternating pretty regularly. 



