140 



CRETACEOrS LxV:\rEIJJBR ANCHTA. 



liiniKirls. — Internal casts of Cijjirutu are found commonly in the Hytbe Beds 

 of Hythe, etc. Those from the " rag " have their original form well preserved, but 

 the specimens found in the softer greensand beds are more or less crushed. One 

 example of tlie same species with the shell preserved has been obtained from the 

 Eower Greensand between Atherfield and BlnekgaTig. The form of t1ie shell 



'';f*<^ 



Fio. 22.— Cypiinrt Smeerhyi, d'Oib. Lower Greensand, Parliam Park. Britisli Museum, No. 5933. 

 Internal cast. Left valve, and dorsal view of both valves, x ^. 



resembles that of C. Uiwolatd (see below), but the anterior curvature of the 

 unibones is considerably less, and the postero-dorsal margin of the shell is less 

 convex. It is difiicult to determine satisfactorily the affinities of this species until 

 more specimens with the shell have been ol)tained. It may l)e identical with the 

 form from tlie Up])er Ajitian of 8te. Croix and tlie I'ei'te-du-RhAne referred l)y 



