PLATE XXIX. 



Page. 

 OSTKEA LINGUAFELIS Whitfield 223 



Fig. 1. View of the cast described. 

 OSTREA GLAUCONOIDES Whitfield .' 222 



Fig. 2. View of a cast of a lower valve. 

 Pecten Kneiskerni Conrad 224 



Fig. :i. View of the type specimen as obtained by a gutta-percha cast in the natural mold. 



Fig. 4. View of an internal cast of a left valve showing the radii flattened and indistinct. 



Fig. 5. View of the exterior of a right valve as obtained from the natural mold. 

 Pecten Rigbyi Whitfield 226 



Fig. 6. Enlarged view of the type, a right valve, obtained from the natural mold. 

 Gryph^ A vesicui AKis Lamarck 224 



Fig. 7. Vertical view of the cast described. 

 8. Lateral view of the same. 

 AviccLA AXNOSA Courad 226 



Fig. 'J. If the figure be turned so as to bring the point at the right end downward, its 

 resemblance to a fragment of a univalve shell will be readily seen. 

 AxiXEA CoxRADi Whitfield 230 



Fig. 10. Upper view of the cast described. 

 11. Outline profile of the same. 

 NucULA Circe Whitfield 227 



Fig. 12. View of the cast of a left valve, natural size. 

 NUCULARIA secunda Whitfield 229 



Fig. 13. View of a right valve, natural size. 

 14. Enlarged view of the same. 

 NucuLAXA albaria Conrad 228 



Figs. 15 and 16. Views of two specimens showing the extremes in form. 

 Crassatella alta Conrad 234 



Fig. 17. View of an imperfect cast which is referred to this species. 

 Crassatella obliquata Whitfield 235 



Fig. 18. View of an internal cast of a left valve showing the massive hinge plate and 

 teeth. 



326 



