PLATE XIX. 

 LEiorrERiA Dekayi. 



Pago 164. 

 See Plate-s 20 and 88. 

 Vig. 1. .\ .small left valve. The specimen shows no imlieations of rays such a.s are represented in tin- 

 fignre. Hamilton gi-oup. C'ooperstown, N. T. 



ACTINOPTEKIA BOYDI. 



Page 11.1. 

 See Plate 84. 

 Fi(js. 2, 3. Two left valves preserving the surface onianientation. 



Hamilton group. Schoharie Co., N. Y. 

 Fig. 4. A left valve. 

 Fig. "). A small left valve. 



Hamilton group. Jefferaon, Schoharie Co., N. Y. 

 Fig. <>. A right valve with an unusually extended wing. 



Hamilton group. Fnltonham, Schoharie Co., N. Y. 

 Fig. 7. The exterior of a right valve, as obtained from a gutta-perrha inlln■L■^•^i(>rl of the natural monhl, 

 showing the spinous processes of the lamell.T. 



Hamilton gi-oup. PuUonham, Schoharie Co., N. Y. 

 The preceding figures represent the forms desciibed as Amada qiMclrtila, Conrad. 

 Fig. S. A .small left valve. The ear should be represented as somewhat oblique. 



Hamilton group. Jefferson, Schoharie Co., iV. Y. 

 Figs. 9-11. Thi-ee left valves showing gradation in size and slight differences in form and surface char- 

 acter. 

 Fig. 12. A small right valve enlarged to two diameters. Another figure of this specimen is gi\en of the 

 natural size in fig. 17, pi. 84. 



Hamilton group. Hamilton, Madison. Co., N. Y. 

 Figs. 18-1."). Three left valves diftering slightly in form ami surface ornaments. 



Hamilton group. Schoharie Co., N. Y. 

 Figs. 10-20. A series of left valves reiire.senting the type A. Boydi of Conrad. 

 Figs. 21-23. Right valves asst)ciated with and corresponding to the preceding. 

 Fig. 24. Two individuals, each retaining both valves in contact. 



Hamilton group. Figs. 16 and 17 are from Schoharie county ; the othere are from 

 Onondaga and Madi.^on counties, N. Y. 

 Figs. :iii. :i7. Two large left valves. 



Hamilton group. Caze:noma, Madison Co., N. Y. 

 Fig. 28. The i-ight valve of the specimen, fig. 26, showing the comparative .size of the two valves. 

 Fig. 29. Cardinal view of the preceding. Another view of the left valve is given on plate 84, fig. 16. 

 Fig. 30. A right valve showing unusually fine concentric stria. 

 Hamilton group. Cazenovia, N. Y. 



ACTINOPTERIA SUBDECUSSATA. 



Page 110. 

 See Phite 17. 

 Fig. 25. A left valve showing the characters a.s preserved in a coarse shale. 

 Hamilton group. Cazenovia, N. Y. 



ACTINOrXERIA PEROBLIQUA. 



Page 116. 



See Plate 84. 



Fig. 31. The right valve of the .specimen described. Tin' left valve of this specimen is figured on plate 84, 



fig. 14. Hamilton grouji. Cazenovia, JV. Y. 



