Figs. 
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Figs. 
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Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
PLATE LIY. 
Gkammysia bisulcata. 
Page 359. 
See Plates 56, 93. 
1-5. Young and medium-sized specimens presenting the usual characters of this fossil. 
6. A left valve in which the stronger folds are obsolete, presenting characters which are partially 
shown in figs. 4 and 5. 
7. The left side of a larg-e individual preserving the iisual characters. 
Hamilton group. Madison Co., JY. I r . 
8. 9. Left side and anterior view of a partial cast preserving the natural form. 
Hamilton group. Madison Co., N. Y. 
10. A specimen preserving the two valves in conjunction. 
11. The right side of a specimen which has been vertically compressed. 
Hamilton group. Madison Co., N. Y. 
12. The right side of a flattened specimen showing the valves retained in conjunction by the hinge 
ligament. 
13. The left side of a smaller individual. 
Hamilton group. Fultonham, Schoharie Co., N. Y. 
14. A specimen preserving the two valves in conjunction. 
Hamilton group. Bear’s gulf, Schoharie Co., IV. Y. 
15. An unusually large individual preserving the two valves in conjunction with the ligament partially 
preserved. 
Hamilton group. G-eneseo, Livingston Co., JSF. Y. 
16. A specimen preserving both valves and having an unusually rotund form. See fig. 1 of plate 56. 
Hamilton group. Fultonham, Schoharie Co., 2V. Y. 
