PLATE LXXVIII 



PAGE 



Figs. 1, 2. ACTIXOPTERIA VIRGINICA Ohern n. sp 458 



1. Imperfect left valve, questionably referred to this species. Hancock. 



2. Left valve of type. Four miles southwest of Keyser, W. Va. 



Oriskany formation, Ridgely member. 



Fig. 3. AVICULOPECTEX ? CUMBERLAXDEXSIS Ohern n. sp 460 



Left valve of type. Helderberg formation. 



Fig. 4. AVICULOPECTEN TEXT-ILAMELLATI'S Hall 461 



Right valve partly exfoliated. New Scotland formation, New York. 



Fig. 5. MEGAMBOXIA LAMELLOSA Hall 462 



Left valve. Oriskany formation, Ridgely member, Cumberland. 



Figs. 6, 7. CYPRICARDIXIA CF. LAMELLOSA Hall 463 



6. Left valve. 



7. The same enlarged to nearly three diameters. 



New Scotland formation, New York. 



Fig. 8. CYPRICARDIXIA SUBLAMELLOSA Hall 463 



Right valve. New Scotland formation, New York. 



Figs. 9, 10. ILIOXIA SIXUATA Hall 464 



9. The right valve of the specimen. 

 10. Cardinal view of the same. 



Manlius formation, New York. 



Figs. 11, 12. PTERIXEA HALLI Clarke 450 



11. Left valve. 



12. Left valve partially exfoliated. 



New Scotland formation, New York. 



