PLATE XLIII 



PAGE 



Fig. 1. CYPBIMERIA MAJOR Gardner n. sp 689 



Hinge of gerontic right valve. Monmouth formation, Brightseat, 

 Prince George's County, U. S. National Museum. 



Figs. 2, 3. SPISULA (CYMBOPHORA) BERRYI Gardner n. sp 708 



2. Exterior of right valve. X 2. 



3. Dorsal view of double valves. X 2. 



Monmouth formation, Brightseat, Prince George's County. 



Figs. 4, 5. SPISULA (CYMBOPHORA) WORDEXI Gardner n. sp 709 



4. Interior of left valve. 



5. Exterior of same. 



Monmouth formation, Brightseat, Prince George's County. 



Figs. 6, 7. CORBULA CRASSIPLICA Gabb 713 



6. Exterior of right valve. X 5. 



7. Double valves from left side. X 5. 



Monmouth formation, 1 mile west of Friendly, Prince George's 

 County. 



Figs. 8-10. CORBULA TERRAMARIA Gardner n. sp 716 



8. Exterior of right valve. X 3. 



9. Interior of same. X 3. 



10. Double valves from left side. X 3. 



Monmouth formation, Brightseat, Prince George's County. 



