PLATE XXII. 

 Leptodesma ? sp. iudet. 



Fig. 1. An obscure tight valve of an indeterminate character. 



Chemung- group. Ithaca. X. T. 



Leptodesma complanati m. 



Page "7. 

 Fig. 2. The left valve described. The striae should turn backward along the him;-.' posterior to the beak 

 Chemung; group. Philipsburg, Alleghany, Co., 2V". Y. 



Leptodesma Becex 



Page 185. 



Fig. 3. A large right valve. 



Chemung group. Corning, Chemung Co., X. Y. 

 Fig. 4. A smaller imperfect example. 



Chemung group. Near Portville, Cattaraugus Co., N. Y. 

 Pig. 5. A small left valve showing the form and proportions of the shell. 



Chemung group. Corning, N. Y. 



Leiopteeia Toereti. 



Page 174. 

 See Plate 88. 

 Figs. 6, 7. Two left valves, fig. 7, showing the characters of the species. 



Chemung group. Fig. li. from Panama; fig. 7, from Salamanca, X. Y. 



Leptc >desma Matheri. 



Page 19S. 

 See Plate 89. 

 Fig. 8. An imperfect left valve of medium size. 

 Fig. 9. A right valve. 



Fig. 10. A small left valve. The body of the valve is represented as too broad. 

 Chemung group. Bradford. McKean Co.. Pa. 



Leptodesma potexs. 



Page 188 



See Plates 21 and 89. 

 Fig. 11. A right valve. 



Chemung group. Napoli, Cattaraugus Co., N. Y. 

 Fig. 12. A similar left valve. The extremity of the wing should be represented as acute as in tig. 19. 



Chemung group. Near Olean, X. Y. 

 Fig. 19. A large left valve. 



Chemung group. Portville. Cattaraugus' Co., X. Y. 

 Fig. 2li. A more elongate form referred to this species with some doubt. 



Chemung group. Randolph. Cattaraugus Co.. X. Y. 

 Fig. 21. A large elongate left valve. 



Chemung group. Near Cassadaga, Chautauqua Co.. X. Y. 



Leptodesma dmb< inatum. 



Page 19S. 

 See Plate 90. 

 Fig. 13. The left valve described. Another figure of this specimen is given on plate 90. tig. V. 

 Chemung group. Twenty Mile creek, Cliautauqua Co., X. Y. 



