PLATE V. 

 Ptku in< (pecten Vertumn US. 



Page 71. 

 See Plate 83. 



Pigs. 1-6. Left valves of various sizes, showing --^li^rb t variations in outline, and considerable variation in 



the number and strength of the rays. 

 Pig. 7. A small right valve. The byssal sinus is not represented sufficiently deep 

 Pig. 8. A specimen presen ing both \ alves, showing their comparative form and surface ornamentation. 

 Hamilton group. Schoharit Co., X. Y. 



AVICUT.OPECTEN FASCICULATUS. 



Page 11. 



See Plate 81. 

 Pigs. 0. 10. Two small left valves. 



Hamilton group. PMonham, Schoharit Co . X. T. 

 Pig. 11. A. left valve. Another figure of this specimen is given on plate 81, fig. 3, showing the concentric 

 stria. 



Hamilton group. Coxtleton, Ontario Co., N. Y 

 Pig. 12. A lefl valve which is much produced posteriorly. The specimen is imperfect at the beak, and is 

 restored in the figure. 



Hamilton group. FuXtonham, Schoharie Co., -V. Y. 

 Pijy. 13 An imperfect left valve, showing strong f'a-ricles of radiating stria-. 

 Pigs. 14. 15. '1'wo large lefl valves, with simple thread-like stria' ornamenting the surface. 

 Pig. 16. A small right valve of this species 



Hamilton group. Schoharit Co., X. Y. 

 Pig. 17. A left valve presenting great irregularities in the radii, due to accident and intermittent growth. 



Hamilton group, Cazenovia, .V. v. 



AVICULO PECTEN PRINCEPS. 

 Page 1. 

 See Plates 1, 6. 24 and SI. 

 Fig. 18. A small left v ah e preserving a portion of the test. 



Hamilton group. Canandaigua lake, X. Y 

 Big. L9. A portion of the test enlarged, showing the surface ornamentation. 

 Pig. °.:i. An imperfect left valve. 



Hamilton group. Western X. Y. 

 Fig. 24. An entire and characteristic right valve 



Hamilton group. Cazenovia, N. 1 



AVICULOPECTEN FORMIO. 

 Page 9. 

 20 \u imperfect left valve of the species. The margins of both ears are represented as too concave 

 m the ligure. 



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



Fig. 21. A. smaller speci n retaining both valves. 



Hamilton group. Madison Co., X. Y. 



AVICULOPECTEN PhORCUS. 

 Page 10. 

 Fig. 2'J. A left valve preservings nearlj entire outline. 



Hamilton group. Schoharie Co., X. Y. 



