PLATE LVll. 

 Gkammysia alveata. 



Page 370. 

 See Plate 60. 

 Fig. 1. Cardinal view of a specimen vertically compressed. 

 Hamilton group. Chenango Co., 2f. Y. 

 Fig. 2. The ventral view of a specimen vertically compressed. 

 Hamilton gi-oup. Madison Co., N. Y. 



GrAMMYSIA CIRCULARtS. 



Page 36i. 



See Plate 58. 



Fig. 3. Two valves in conjunction which have been partially denuded of the shell, showing muscular scare 



and pallial line. 

 Fig. 4. The i-ight side of a cast of the inteiior showing muscular scars and pallial line. 

 Fig. 5. Anterior view of the same specimen. 



Hamilton group. Schoharie Co., N. Y. 

 Fig. 6. Anterior view of a specimen somewhat vertically compi-essed. 

 Chemung group. Ithaca^ N. Y. 



Gkammysia nodocostata. 



Page 3B0. 

 See Plates 55, 56, 96. 



Figs. 7, 8. Cai-dinal view and right side of a large individual. 

 Hamilton group. Madison Co., N. Y. 



Gkammysia magna. 



Page 362. 

 See Plate 56. 

 Fig. 9. View of a crushed specimen, showing the escutcheon and ligamental ai-ea with a portion of the 

 ligament. 



Hamilton group. Pompey, Onondaga Co., N. Y. 



Gkammysia kkkota. 



Page 3«8 

 See Plate 56. 

 Fig. 10. The umbonal and anterior portion of a right valve. 



Hamilton group. Near Bear's gnlf, Sc-Jutharie Co., iV. Y. 



