PLATE XII. 



Nemodon brevifrons Conrad ^^^^ 



Fig. 1. View of a specimen identified and labeled by Mr. Conrad, from Haddonfield, N. J. 

 2. Enlarged view of the binge of the same. 

 Nemodon Eufaulexsis Gabb 



Fig. 3. View of a partial cast from the limestone nodules of the Lower Marls at Holmdel 

 N.J. 



4. Enlargement of the binge of the same. 



5. Enlargement (two diameters) of a specimen from Haddonfield, N. J., one of the 



types. 



Nemodon angulatum Gabb ^ 



Fig. 6. View of the type specimen, natural size. 

 7. Enlarged cardinal view of the same. 



Nemoarca Cretacea Conrad 



Fig. 8. Enlargement to two diameters of a cast from the iron nodules from" Keyport, N." j" 



9. View of the exterior (tJiree diameters) of one of the type specimens. 



10. Diagram of the hinge of the same. 

 Breviarca Saffordi Gabb 



Fig. 11. View of the exterior, natural size, of one of the type specimens, from Haddonfield 

 N. J. ' 



12. Enlargement of the hinge of the same. 



Arca (Trigoxarca) transversa Gabb go 



Fig. 13. Left side of a specimen from Mullica Hill, N.J. 



14. Right view of Mr. Gabb's type specimen. 



15. Cardinal view of the same. 



16. View of a small cast, more angular on the umbonal ridge than the others, and 



showing the hinge features. 



Trigonarca cuneiformis Conrad go 



Fig. 17. Enlarged view of the exterior of the type specimen, Haddonfield,' N.' J."(seven 

 diameters). 

 18. Outline view of the interior of the same equally enlarged. 



IDONEARCA TiPPANA Conrad 



Fig. 19. View of the cast of a left valve from the deep cut of the Holmdel and Keyport 

 turnpike, N. J. 



20. Outline profile of the same, showing convexity. 



21. Inside of a valve from near Prairie Bluff, Ala., to show the hinge features 

 Arca altikostris Gabb 



Fig. 22. Right view of the original type of the species. 

 23. Cardinal view of the same. 



292 



