Ptycho. 



838 



ating striae crossed by distinct concentric striae ; resembles P. 





eucrate^ but is less gibbous, longer, and without angularity 

 along the body. Chemung conglomerate at Panama, N. Y. Also 

 Kandall's Warren specimen N'^. 9502. VIII g. 



Ptychopteria falcata, Hall, Pal. N. Y. Vol. V i, 1884, 

 ^"' ^' .^^""^mmm^ 7 page 136, pi. 85, fig. 6, entire 



left valve with surface mark- 

 ings ; 7, smaller left valve ; 

 shell comparatively longer, 

 Pa/,lViffJt^4^ body more oblique, and wing 

 Vol,V I tp^9S smaller than in P. ihetis. In 

 an Upper Chemung sandstone and conglomerate at Allegheny 

 Springs, Warren Co., Pa. Specimens in Kandall's collections 

 at Warren, Pa., specimen 9612, wrongly labelled Cypricardia ; 

 also spec. 886-2. VIII g. 



Ptychopteria galena, Hall, Pal. N. Y. Vol. V i, 1884, page 



142, pi. 85, ^^. 29, left valve 

 pressed flat; 30, smaller ditto 

 normal; (31, omitted); fine, reg- 

 ular, interrupted or undulating 

 . . radii, and very fine concentric 

 /fe/.A/XK/,/?//5 g^j..gg^ crowded into irregular 



bundles and lamellose on front part of shell ; interior un- 

 known. In lower beds of Upper Chemung^ at Warren, Pa- 

 Specimens in Randall's collections at Warren, Pa. Nos. 9499, 

 9450,9501, 9502 A, 9623, 9624, 9625 ; wronglv labelled '^ Yoldia V 

 VIII g, 



Ptychopteria lata, Hall, Pal. N. Y. Vol. V i, 1884, page 

 145, pi. 85, fig. 23, entire left valve; 24, larger ditto ; 25, right 

 valve showing its comparatively stronger wing-fold ; concentric 

 striae crowded into bundles at unequal distances and wavy. 





Vni 





