PLATE LXXXV 



PAGE 



Figs. 1, 2. PLATYCERAS TENUILIRATUM Hall 476 



Upper and dorsal views of a large individual. New Scotland forma- 

 tion, New York. 



Fig. 3. PLATYCERAS ANGULARE Rowe n. sp 476 



Dorsal view of type. Oriskany formation, Ridgely member, Warren 

 Point, Penna. 



Figs. 4-6. PLATYCERAS MULTISINUATUM Hall 477 



4, 5. Upper and dorsal views of a small specimen. 

 6. Upper view of a partially exfoliated specimen. 

 New Scotland formation, New York. 



Fig. 7. PLATYCERAS PLATYSTOMUM Hall 477 



View of the right side of a specimen, the apex of which is broken 

 off. New Scotland formation, New York. 



Figs. 8, 9. PLATYCERAS SPIRALE Hall 478 



Views of internal cast. Helderberg formation, New Scotland mem- 

 ber, Corriganville. 



Figs. 10-13. PLATYCERAS GRACILE Ohern n. sp 478 



10. 12. Two views of individual without plications. 



11. 13. Views of strongly plicate specimen. 



Oriskany formation, Ridgely member, Cumberland. 



70 



