146 .4. E. Verrill — Molbisca of the Neic E)i(/hntd Coaxt. 



Lengtli of the body and head, to base of arm, 27'"'" ; length of 

 body to edge of maulle above, 20'""^ ; breadth across body, 14""" ; 

 breadth of head across eyes, ir"""; diameter of eye-ball, 4-5"^™; 

 length of dorsal arms, 7""" ; length of second pair of arms, 9"^"^ ; length 

 of third pair, 14'^'"'; length of ventral arms, 7-5'^'"^; length of hecto- 

 cotylized arm, 11""" ; height of largest specialized suckers, 3""" ; 

 diameter, 3'""'. 



Station 2099, N. latitude 37° 12' 20", W. longitude 69° 39', in 2949 

 fathoms, (No. 35,268*). Steamer Albatross, 1883. 



G-ASTROPODA. 

 Pleurotomella Verriii. 



Amer. Jour. Science, v, p. 15. 1882; Catal. Marine Molliisca, these Trans., v, p. 

 453, 1882. 



This genus was originally proposed for P. Packardii, first taken 

 in deep water in the Gulf of Maine. This species is remarkable for 

 the delicacy and beauty of its sculpture and the great depth of its 

 subsutui'al sinus. The subsequent discovery of numerous other 

 related species inhabiting the deep waters, off our coast and in other 

 regions, has rendered it necessary to enlarge the limits of the genus 

 and to modify its characters. 



As at present understood, this genus is intended to include those 

 species which have a rather broad and very distinct subsutural band, 

 crossed by excurved lines of growth corresponding to the form of the 

 posterior sinus of the lip, which is situated a little below the suture 

 and is always pretty well-developed, but is sometimes broad and 

 shallow, and at other times narrower and very deep. The outer 

 lip is always thin and sharp, without any apjsearance of a varix, nor 

 is there any deposit of callus on the body-whorl, in front of the aper- 

 ture. The canal is well developed, generally constricted at the base 

 and somewhat elongated, and usually but slightly curved. In a few 

 of the species, doubtfully referred to tlie genus, it is short and wide. 

 The coluniella-margin is more or loss sinuous. The nucleus differs in 

 sculpture, and usually in color, from the rest of tlie whorls, and is 

 generally minutely cancellated by line raised lines running obliquely 

 in opposite directions. The remaining whorls ax'e elegantly sculp- 

 tured by longitudinal ribs and revolving cinguli, and usually have a 

 distinct shoulder or carina, which is frequently nodulous, below the 



* The numbers given in this paper are those used in tlie permanent catalogue of the 

 mollusca, in the National Museum. 



