i-i A I i. \ atinm 



A \H I LOPE( l I.N DOL 1BRIFORMIS. 

 Page 36. 

 Fig. 21. A right valve enlarged to two diameters. The earn should Bbow, in tin- figure, raya similar t.. 

 those "n the bods of the valve. This figure is from the original specimen of the Bpecies. 

 mp. Philipsburg, N. Y. 



A\ 101 LOPEQTEN CONVEX1 8. 

 Page 38. 



pw» 22. A left valv ilarged to two diameters. The anterior ear should show a slight sinus in the 



margin for the byssus. 

 Fig. I':!. A profile of the preceding! showing the convexity oi the valve. (Original < ■ f tiir. 6, p. 284, < leolog. 

 Rept. Fourth Dist N. I., 



Chemung group. Rockville, N. 1*. 



A VICULOPECTKX SIGH \ I I-. 



Pap- 29. 



Fig. 24. A. left valve enlarged to two diametei's, showing the form and surface markings. (Original of 

 fig. 5, p. 264, Geolog. Rept. Fourth Dist. N. V. i 

 Chei e group. Bockville, N. 1". 



LyRIOPECTEX POLYDORl S. 

 Page 50. 

 25. The left valve described. Tin- byssal sinus should l»- deeper than represented. 



i I ing group. Cassadaga, N. Y. 



Lyriopecten tricostatus. 



I'-.t^r 18. 



See Plates 4 and LO. 



\'\is. 26. An enlargement to two diameters of a portion of the snrfa f a s] imen of tlii> species. 



Chemung group Near Elmira, N. 1'. 



A\ ICUIiOPECTEN r i: \ I 18. 



i"a;;e 39. 



See Plate 81. 

 Fig. 27. A left valve, showing the form and surface markings. The specimen also shows the muscular 

 impression and pallial line. 



( !hemung group. /.' A '. 1". 



I _ js \ larger specimen of the same. Another tigure is given on plate 81, showing more clearrj 

 the characters of the species. 



Chemung group. Near Salamanca, .V. Y. 



Avici lopecten celsi s. 



Paee 23 

 29, : ;< ■ A right valve, natural size and enlarged. 



Chemung group. Salattianra, .Y. Y. 



A\li'l LOPECTEN ELUPTICUS. 

 Page 25. 

 31. A nearly entire left valve nt'tliis species. 



Chemung group. MeadvMe, Pa. 



A\ ICUI.Ol'ECI i;\ PATULU8. 

 Page J4 

 Fig. 32. A small right valve as obtained from the impression in the matrix. The ears are partiallj 

 restored in the figure. 



Chemung group. Salamanca, .V. 1'. 

 Fig. ;i;!. A large left valve, showing the characters of the shell as obtained from an impression in a fine 

 conglomerate. The hinge-line should be represented as straight. 

 Chemung group. Near Salamanca, -Y. ST. 



