PLATE XLIY. 
Goniophora truncata. 
Page 298. 
See Plate 42. 
Fig. 1. The right side of a crushed specimen showing the surface markings. 
Hamilton group. Shore of Cayuga lake, N. Y. 
Fig. 2. The cardinal view of the preceding. 
Fig. 3. The right valve of a large individual preserving the surface markings, and showing the natural 
form of the shell. 
Fig. 4. A fragment of a right valve showing the surface markings. 
Hamilton group. Delphi, N. F. 
Fig. 5. A portion of a right valve from a gutta-percha impression of the natural mould. 
Goniophora carinata. 
Page 301. 
See Plate 42. 
Figs. 6-8. A series of specimens showing the gradation of form and size. 
Hamilton group. Schoharie and Otsego Co's, N. Y. 
Goniophora trigona. 
Page 302. 
See Plate 42. 
Fig. 9. The left valve described. 
Chemung group. Franklin, Delaware Co., N. F. 
Goniophora Glauous. 
Page 299. 
See Plate 43. 
Fig. 10. A large right valve in which the cardinal slope is narrowed from compression. 
Fig. 11. A right valve. 
Hamilton group. Madison Co., N. Y. 
Fig. 12. A partial cast of a right valve of short form, showing the anterior muscular impression and pallial 
line. Hamilton group. Near Apulia, Onondaga Co., N. Y. 
Fig. 13. A cast of the interior of a left valve showing the hinge area, the anterior muscular impression and 
pallial line. 
Hamilton group. Bear's Gulf, Schoharie Co., N. Y. 
Fig. 14. A gutta-percha impression from the preceding specimen. 
Fig. 15. An unusually elongate left valve of this species. 
Hamilton group. Kellogsville, Cayuga Co., N. Y. 
Fig. 16. A cast of a right valve preserving some remains of the shell, and showing the anterior muscular 
impression and pallial line. 
Hamilton group. Schoharie Co., N. Y. 
Fig. 17. A right valve of a specimen of medium size. 
Hamilton group. Madison Co., N. Y. 
