PLATE LVI. 
Grammysia bisuloata. 
Page 359. 
See Plates 54, 93. 
Fig. 1. A left valve of a large individual of broad form. 
Hamilton group. Ludlowville, N. Y. 
Grammysia nodocostata ? 
Page 360. 
See Plates 55, 57, 96. 
Figs. 2, 3. The right and left sides of a specimen which is obliquely compressed and distorted. 
Hamilton group. Fidtonham, Schoharie Co., N. Y. 
Grammysia magna. 
Page 362. 
See Plate 57. 
Fig. 4. The right side of a partial cast of the interior. 
Hamilton group. Madison Co., N. Y. 
Fig. 5. The right side of a specimen preserving the two valves in conjunction. 
Lower Chemung group. Ithaca, N. Y. 
Fig. 6. A large left valve which is a partial cast of the interior, preserving only the liner striae. 
Fig. 7. A partial cast of a light valve preserving on the middle and anterior portions the stronger un¬ 
dulations. 
Hamilton group. Schoharie Co., N. Y. 
Grammysia erecta. 
Page 363. 
See Plate 57. 
Fig. S. An imperfect right valve preserving the umbonal and anterior portion. 
Hamilton group. Fidtonham, Schoharie Co., N. Y. 
