124 POPULAR BRITISH CONCHOLOGY. 



conical, with the apex curled in front of the opening. 

 The row of cirrhi on the foot does not extend to the 

 hinder part. 



III. Emarginula. — The fissure for the anal tube in Emar- 

 ginula is in the basal margin of the shell. The cirrhi 

 above the foot form a complete circle. The peduncles 

 of the eyes become more distinct in this genus. The 

 shells of our British species are as follows : — 



E. reticulata : white, high, with pits between the cross-bars. 



U. rosea : rarely rose-coloured ; very small ; the back very 

 much arched, and apex curved ; deeply cross-barred. 



B. crassa : white, large, ribbed. 



