PLATE XXII—Continued. 
Leptodesma umbonatum, var. depress um. 
Page 199. 
See Plate 90. 
Fig. 14. The specimen described. Another figure of this specimen is given on plate 90, fig. 10. 
Chemung group. Napoli, Cattaraugus Co., N. Y. 
Leptodesma naviforme. 
Page 200. 
See Plate 23. 
Fig. 15. The left valve described. The anterior end should be represented as more extended and acute, 
and the extremity of the wing a's mucronate. 
Chemung group. Near Ithaca, N. Y. 
Leptodesma potens, var. juvens. 
- Fig. 16. A left valve. 
Chemung group. East Randolph, Cattaraugus Co., N. Y. 
Leiopteria Chemungensis. 
Page 172. 
Figs. 17, 18. Opposite views of the original specimen showing the left and right valves. The right valve is 
imbedded vertically in the rock and has been much shortened by the shrinkage or compression 
of the layers, while the surface of the shell has been slightly wrinkled from the same cause. 
Chemung group. Eight miles north of Binghamton, N. Y. 
Leptodesma Lysander. 
Page 216. 
See Plate 90. 
Fig. 22. A left valve. The figure is partially restored and should represent the body as considerably wider. 
Chemung group. Mansfield, Tioga Co., Pa. 
Leptodesma extenuatum. 
Page 207. 
- See Plate 90. 
Fig. 23. An imperfect left valve. Another figure of this specimen is given on plate 90, fig. 17. 
Chemung group. Philipsburg, Alleghany Co., N Y. 
Pteronites ROSTRATUS. 
Page 238. 
Fig. 24. The left valve described. 
Chemung group. Rockville, N. Y. 
Pteronites profundus. 
Page 237. 
Fig 25. A small left valve. 
Chemung group. New Albion, Cattaraugus Co., N. Y. 
Fig. 26. A larger example. The anterior side should show regular concentric undulations. 
Chemung group. ' Randolph, Cattaraugus Co., N. Y. 
Fig. 27. A large individual, imperfect on the anterior end. 
Chemung group. Near Olean, N. Y. 
Leptodesma aliforme. 
Page 220. 
See Plate 91. 
Fig. 28. A right valve. This specimen is redrawn on plate 91, fig. 2, and represents more clearly the 
specific characters. 
Chemung group. Near Angelica, Alleghany Co., N. Y. 
