PLATE XII. 



CucuLLA<: a (continued) . 



FIGS. 



1 — 5. C. glabra, Parkinson. Greenland, Blackdown. (P. 57.) 



1 a, b, 2. Wiltshire Collection, Woodwardian Museum. Left valves. 



3. Woodwardian Museum, a, right valve; b, dorsal view of same specimen. 



4. — — Left valve. 



5. Elongate variety. Wiltshire Collection, Woodwardian Museum. Left valve. 



6—8. C. obesa, Pict, and Camp. Gault, (P. 61.) 



6. Folkestone. Wiltshire Collection, Woodwardian Museum. Young form. Eight 

 valve. 



7. Same locality and Collection, a, left valve ; b, dorsal view of same. 



8. Cambridge Greensand (derived from the G-ault). Woodwardian Museum. 

 Internal cast, a, left valve ; b, posterior view. 



