PLATE VIII. 



Grammatodon (continued). 



FIGS. 



1, 2. G. securis (Leym.), Speeton Clay (zone of Bel. brunsvicensis), Speeton. 

 (P. 44.) 



1. Collection of G. W. Lamplugh. Dorsal view x 2. 



2. York Museum. Left valve, with part of shell preserved. 



3—8. G. carlnatus (Sow.). (P. 45.) 



3. Greensand, Blackdown. "Wiltshire Collection, "Woodwardian Museum, a, outline 



of left valve ; b, same xl|; c, dorsal view of same x 1|; d, hinge and area 

 of same X 2. 



4. Same locality and Collection, a, left valve ; b, dorsal ; c, anterior view. 



5. Same locality and Collection. Right valve. 



6. Gault, Lyme Eegis. Woodwardian Museum. Left valve. 



7. Gault (zone ii), Folkestone. Museum of Practical Geology, No. 1632. a, right 



valve ; b, dorsal. 



8. Gault, Folkestone. Wiltshire Collection, Woodwardian Museum. Left valve. 



The ventral part is crushed in, so that the shell appears too long pro- 

 portionately. 



Genus Trigonoarca, Conrad. 



9, 10. T. Passyana (d'Orb.). (P. 47.) 



9. Greensand, Kingskerswell. British Museum, No. L 1853. a, right valve ; b, 

 cast of hinge ; c, ornamentation x 3. 

 10. Chloritic Marl, Maiden Bradley. Woodwardian Museum. Internal cast, a, right 

 valve ; b, dorsal. 



Genus CucuLLiEA, Lamarck. 



11 — 13. C. Comueliana (d'Orb.). Lower Greensand, Atherfield. (P. 50.) 



11. Eight valve. Woodwardian Museum. Above the Crackers. 



12. Right valve. Woodwardian Museum. Crackers. 



13. Left valve. Woodwardian Museum. Above the Crackers. 



