PLATE XXIV 



PAGE 



Fig. 1. PAXEXKA ALTERNATA Hall 223 



View of a large right valve showing strong radii. Oldtown. Romney 

 formation, Onondaga member. 



Figs. 2, 3. PAXEXKA OBSOLESCEXS Kindle n. sp 224 



2. View of right valve of type. Oldtown. 



3. Fragmentary right valve. Ridgeville, W. Va. 



Romney formation, Onondaga member. 



107 



