498 TROCHIDiE. 



straight or subretuse ; it is either devoid of all colour, or 

 more rarely has the belts of a pale golden yellow. The 

 elongation of the whorls, which are about six in number, 

 is slow ; they are rather narrow^, moderately ventricose, 

 and appear the more distinctly separated from the carinse 

 not touching the suture either above or below : the apex 

 is small, yet can scarcely be termed acute. The basal cir- 

 cumference is angulated ; the angle for the most part is 

 a right one, the base itself is flattish or hardly at all 

 rounded, and is merely encircled with two broad grooves 

 near the margin, and about four round the imperforated 

 axis, the broad strip between these two sets being devoid 

 of all sculpture whatsoever. The interstitial spaces be- 

 tween the sulci assume the appearance of depressed belts, 

 but are not distinctly raised above the general level of the 

 superficies. The mouth is nacreous, subquadrangular, 

 much broader than it is long, and occupies about a third of 

 the entire length of the shell, and about one half of the 

 basal diameter : it merely exhibits the vestiges of the 

 external carinfe, not being distinguished by any peculiar 

 sculpture of its own. The outer lip is acute ; the pillar 

 white, narrow, straightish, and not much rounded. Few of 

 our British specimens attain to the length of half an inch. 



The animal, which we were so fortunate as to examine 

 alive, in one of the specimens dredged off Fair Island, is 

 entirely pure white. The head terminates in a rather 

 narrow proboscis and bears two long subulate tentacula 

 which are minutely ciliated ; the eyes are black and 

 placed on rather large peduncles ; the capital lobes are 

 minute and imperfectly developed. The neck-lappets 

 are of moderate size and plain-edged ; the lateral cirrhi 

 are three on each side and rather short and slender as 

 compared with the tentacles ; they are carried closely 



