I'l.ATK I.XW l .0.1. 



A< 1 1 n ' > I ■ I 1:1:1 \ \ru< tlata. 

 Page 191. 

 15. The left valve described showingthe large anterior ear. 



< Ihemung group. 1 Rft. 



All !%• >pi Kill A IS'lVtll. 

 US. 

 See Plate L9. 

 Pig. 16. The left valve of the specimen figs. 26,28,29. plate 19, redrawn Jo show the pallial line ami 

 muscular impressions. 



Hamilton group. Cazewrvia, ZV. )'. 

 Vw. 17. A small right valve showing the hinge characters, pallial line and muscular impression. This 

 figure is the natural size of the specimen represented in figure 12, plate 19. 

 Hamilton group. Hamilton, Madison Co., X. Y. 



Aci'INOPTERIA THJBTA. 

 Page 125. 

 Pigs 18, 19. The right and left valves of the specimen described, 

 Chemung group. Ithaca, N. Y. 



EOTENODESMA BIROSTRATUM. 

 Pi ge 242. 

 See Plate 25. 

 Fig. 20. The left valve repi"esented on plate 23, fig. 30, redrawn to show the extent of the wings. 

 Chemung group. Fraiiklin, I Co., X. Y. 



l'XEKl.NEA ChEMTJNGENSIS. 



Page 98. 

 See Plate 16. 



I'iir. 21. A l.irjre left valve of this s] ies showing the form of the shell and the interrupted rays with the 



fine concentric stria' of the surface. 



Chemung group. Near Bath, N. Y. 



PTERINEA [NTERSTRIAUS. 

 Pagi 

 Pig. 22. An imperfect left valve. 



Chemung group. Chemung Narrows, N. Y. 



PtEIIIXKA ( i »NS1 M ILIS. 



Page 100. 



See Plate 16. 



Fif. r . 2:1. A left valve showing the ligameirtal area, cai-dinal and lateral teeth, pallial line and muscular 



impression. Some portions of the test are remaining on the lower half of the valve. 



Chemung group. '/'. V. 1". 



PTEBINEA ( Yek t imm a) BE VERSA. 

 Page IW 

 Plate 24. 



I .24. The s] imeii n i on plate 24, fig. 6, redrawn to show the absence of strong rays on the 



wing. 



Chemung group. / ira, .V. F. 



