EXPLANATION OF PLATE XLII. 



PTERIA PETROSA (Conrad), .......................................... p. 4 2 9 



1. A complete internal cast of the right valve. 



Cliffwood clay; near Matawan, (/tfp). 



2. An incomplete internal cast of a left valve. 



Wenonah sand; near Marlboro, (130). 



PTERIA LARIPES (Morton), ........................................... p. 431 



3. View of a left valve. (After Whitfield.) 



PTERIA NAVICULA Whitfield, ...................................... '. . .p. 432 



4. View of the type specimen. (After Whitfield.) 



Woodbury clay; Haddonfield, (183}. 



MELEAGRINELLA ABRUPTA (Conrad), .................................. P- 433 



5-6. Views of two internal casts, a left valve and a right valve. 



Navesink marl; near Holmdel, (128*}. 

 7-8. Internal and external views of a nearly complete right valve, 



(x2). (After Whitfield.) 



9. The hinge of a left valve, (x2). (After Whitfield.) 

 Navesink marl; Freehold. 



OSTREA PANDA Morton, .............................................. p. 437 



10. View of a nearly perfect lower valve. 



Marshalltown clay-marl; near Swedesboro, (180). 



OSTREA CRETACEA Morton, ........................................... p. 434 



11. A nearly complete internal cast of the lower valve. 



Cliff^vood clay; Cliffwood Point (105). 



OSTREA CRENUUMARGINATA Gabb, .................................... p. 441 



12-13. External and internal views of a complete single valve, illus- 

 trated by Whitfield. 



Navesink marl; Marlboro. 



OSTREA sp. 



14. View of an internal cast of a lower valve. 



Vincentown sand; near Deal, (122). 



OSTREA SUBSPATULATA Forbes, ....................................... p. 440 



15. View of an internal cast of a lower valve. 



Wenonah sand; Crawfords Corner 



OSTREA PtUMOSA Morton, ........................................... p. 439 



16. An upper valve preserving the shell. 



17. A lower valve supposed to belong to this species. 



Marshalltown clay-marl; near Swedesboro, 



18. Internal cast of a lower valve. 



Wenonah sand; Craivfords Corner (126*). 



966 



