A. E. Verrill — Mollusca of the New England Coast. 219 



Cadulus grandis Verrill, sp. nov. 



General appearance of the shell much like that of C Pandionis, 

 but more than twice as large, without the abrupt bulging at the 

 largest part, which is a characteristic feature of the latter, and with 

 a relatively larger posterior aperture. 



The shell is, for the genus, large and strong, translucent bluish 

 white when living, n^ilk-white when dead, with a highly polished 

 surface, only faintly marked by the lines of growth when perfect. 

 The shell is moderately curved, the greater part of the curvature 

 being behind the middle, and is largest at about the anterior third, 

 the decrease being very gentle and regular in both directions, but a 

 little more rapid towards the anterior end. The dorsal side is a 

 little flattened towards the aperture, which is decidedly oblique and 

 very broad-elliptical. The posterior aperture is relatively rather 

 large, circular, with the edge a little thickened and divided into four 

 rounded notches, the two upper ones being usually a little deeper and 

 farther apart than the two ventral ones. 



Length of one of the largest examples, 15™"' ; greatest diameter, 

 3.51111.1. transverse diameter of the oral end, 3"'"^; vertical diameter, 

 2'5""" ; diameter of the posterior end, 1-3™"'. Some s})ecimens exceed 

 these dimensions. 



This species occurred at station 2052, in 1098 fathoms; station 

 2076, in 906 fathoms, sixteen specimens, mostly living (No. 34,735); 

 station 2084, in 1290 fathoms, three specimens (No. 35,184); station 

 2103, in 1091 fathoms, one specimen; station 2111, in 938 fathoms, 

 one dead specimen; station 2115, in 843 fathoms, six dead speci- 

 mens. From station 2043, in 1467 fathoms, one large malformed 

 specimen occurred, apparently belonging to this species (No. 38,116). 



This species might readily be mistaken for a large form of C. Pan- 

 dionis, but it difters from the latter in having a larger posterior aper- 

 ture, a more nearly circular oral aperture, and especially in the 

 absence of the abrupt bulging at the largest part. The form is 

 usually less curved, although in this respect both species ai-e some- 

 what variable. This shell is, however, much thicker and in every 

 way more robust. 



Cadulus "Watsoni Daii. 



Dall, Bull. Mus. Comp. Zool., vol. ix, p. 34, 1881. 



Tlie specimens referred to this species resemble, in size and general 

 character, C. Pandionis, and, like that species, have the mouth 

 Trans. Conn. Acad., Vol. VI. 28 June, 1884. 



