144 SPECIFIC 



Fig. 2. O. varia. 



Shell equivalve ; about 30 compressed rough and 

 prickly rays ; one ear very small. 



Lister Coi/ch. tab. 178. fig. 15. 



Specimen yellow brown with darker clouds ; ra- 

 ther convex ; rays obsoletely spinous, intermediate 

 spaces not striate; the smaller ear spinous, the 

 larger with wrinkled plaits and 5 spines beneath. 



Inhabits the English coast. 



Fig. 3. O. fasciata. 



Shell equivalve ; 20 rough rays ; intermediate 

 furrows striate ; ears equal, very small. 



Lister Conch, tab. 177. fig. 14. 



Specimen white pellucid, gaping on both sides, 

 within finely striate, margin crenate. 



Inhabits the Atlantic Ocean. 



Fig. 4. O. Folium. 



Shell ovate, obtusely plaited at the sides, para- 

 sitical. 



D' Argenville Conch, t. 19. F. 



Specimen pale purplish brown, underneath in- 



