30 VALVATIDJE. 



2. B. Leachii,* Sheppard. Pl. IV. 



Body whitish, marked with black spots, and golden dots 

 which are visible through the shell ; tentacles rather trans- 

 parent, nearly colourless ; eyes black ; snout bilobed, spotted 

 with black, often reddish at the extremity ; foot slender. 



Shell subconical, moderately thin and transparent, yellowish 

 horn-colour, glossy, with faint spiral striae and stronger lines of 

 growth ; epidermis very thin ; whorls 4-5, very tumid, rounded, 

 body whorl occupying nearly one-half of the length of the shell ; 

 spire with a somewhat obtuse apex ; suture very deep, straightish ; 

 mouth nearly circular, much less angulated above than in B. 

 tentacnlata J outer lip thickish, slightly ribbed internally, very 

 little reflected ; inner lip forming with the other a complete 

 peristome ; umbilicus small, but distinct ; opercuhwi nearly 

 circular, flattish, striated as in B. tentaculata. 



Inhabits situations similar to those in which the 

 last species is found, but it is much less common. 

 It differs from it in being very much smaller, as 

 well as in having a more circular mouth and oper- 

 culum, a deeper suture, and a more distinct umbilicus. 



Var. I. elongata. — Shell smaller ; spire longer. Woolwich 

 Marshes, Northampton, B.C. 

 Var. 2. albida. — Shell white. 



FAMILY III.— VALVATIDiE. 



Body spiral ; tentacles 2, contractile ; eyes placed on the inner 

 side of the tentacles at their base ; foot separated from the 

 snout ; gill extending beyond the margin of the mantle, pro- 

 vided with a contractile feather-like apparatus ; reproductive 

 system androgynous, each individual being both male and 

 female. 



Shell spiral, ventricose, more or less depressed ; peristome 

 complete ; operculum regularly many-spiral. 



* Named after Dr. Leach. 



