PLATE V. 



Fig. 1. Ostrea abrupta d'Orb. var.? Valve 



showing 



plicated exterior. Venezuela. Cre- 



Page 



taceous. Height 25 mm 40 



2. Ostrea abrupta d'Orb. var.? Interior of a larger valve. Venezuela. Cretaceous. 



Height 45 mm 



40 



3. Ostrea puelchana d'Orb. Small variety. Height 47 mm. Union Estate, Brighton, 



Trinidad. Oligocene 40 



4. Ostrea puelchana d'Orb. Same shell as 3. Interior of flat valve 40 



5. Ostrea puelchana d'Orb. Same shell. Interior of convex valve 40 



6. Ostrea thirsce Gabb. Convex valve. Height 28 mm. Soldado Rock. Lignitic Eocene 39 



7. Ostrea thirsce Gabb. Same shell, lateral view 39 



8. Ostrea thirsce Gabb. Flat valve. Height 20 mm. Soldado Rock. Lignitic Eocene . . 39 



9. Ostrea puelchana d'Orb. Large variety. Height 135 mm. Union Estate, Brighton, 



Trinidad. Oligocene 40 



10. Ostrea puelchana d'Orb. Same shell, lateral view 40 



11. Ostrea crenulimarginata Gabb. Smooth and plicated valves. Soldado Rock. Midway 



Eocene 36 



