PLATE VII. 

 Bakbatia (continued). 



FIGS. 



1—3. B. (Scaphula?) Austeni (Forbes). (P. 37.) 



1, 2. Crackers, Atherfield, Leckenby Collection, Woodwardian Museum. 1 a, right 

 valve; lb, ornamentation near postero-ventral angle x 3. 2. Dorsal view of 

 another specimen X 2. 



3. Left valve. Penia-bed, Redcliff. Collection of C. J. A. Meyer. 



4—7. B. marullensis (d'Orb.). (P. 38.) 



4. Left valve. Lower Greensand, Up ware. Woodwardian Museum. 



5. Gault (zone iii), Folkestone. Museum of Practical Geology, No. 11330. a, right 

 valve ; b, dorsal view of same specimen ; c, ornamentation on postero-dorsal area 

 x 4 ; d, ornamentation from near the middle of the valve x 4. 



6. Gault, Folkestone. Wiltshire Collection, Woodwardian Museum. a, right 

 valve; b, dorsal view of same specimen. 



7. Gault, Folkestone. Museum of Practical Geology, No. 6559. Eight valve. 



8. B. rotundata (Sow.). Greensand, Blackdown. The Type, Bristol Museum. 



a, right valve; b, dorsal view ; c, same X 2. (P. 40.) 



9. B. Galliennei (d'Orb.). Chalk Marl, near Lyme Regis. Wiltshire Collec- 



tion, Woodwardian Museum. Internal mould, a, right valve ; 



b, dorsal view of same specimen. (P. 41.) 



10, 11. B. sp. } cf. Geinitzl (Reuss). Chalk Rock (zone of Ret. Reussianum), 

 Cuckhamsley. Montagu Smith Collection, Woodwardian 

 Museum. (P. 42.) 



10. a, portion of wax mould of right valve; b, ornamentation X 5. 



11. Natural internal mould of right valve. 



12. B. sp. Same locality and Collection, a, internal cast of left valve; 



b, dorsal view of same. (P. 42.) 



13. B. ? sp. Same locality and Collection, a, left valve, outline natural size . 



b, same X 2. (P. 43.) 



Genus G-rammatodon, Meek and Eayden. 

 14, 15. G. securis (Leymerie). Speeton Clay (zone of Bel. brunsvicensis), 

 Speeton. Collection of G. W. Lamplugh. (P. 44.) 



! 1. a, b, right and left valves of same specimen. 

 15. a, left valve ; b, ornamentation x 3. 



