PLATE XL 



PAGE 



Figs. 1, 2. CABDIUM EUFALENSE Conrad 664 



1. Exterior of left valve. 



2. Interior of same. 



Monmouth formation, Brightseat, Prince George's County. 



Figs. 3, 4. AXTIGONA (APHRODINA) TIPPANA (Conrad) 681 



3. Exterior of left valve. 



4. Interior of same. 



Monmouth formation, Brightseat, Prince George's County. 



Figs. 5-7. LEGUMEN PLANULATUM (Conrad) Gabb 684 



5. Exterior of right valve. 



6. Double valves from right side. 



7. Dorsal view of same. 



Monmouth formation, Brightseat, Prince George's County. 



Figs. 8-10. CYPRIMERIA DEPRESSA Conrad 687 



8. Interior of left valve. Monmouth formation, Brightseat, Prince 



George's County. 



9. Exterior of left valve. 

 10. Dorsal view of same. 



Monmouth formation, near Oakland, Prince George's County. 



Figs. 11, 12. CYPRIMERIA MAJOR Gardner n. sp 689 



11. Exterior of right valve of young individual. 



12. Interior of same. 



Monmouth formation, Brightseat, Prince George's County. 



