PLATE LXXXVIII 



PAGE 



Figs. 1-3. OKTHOCERAS LONGICAMERATUM Hall 487 



1. Longitudinal section showing curvature of septa. 



2. Internal cast, doubtfully referred to this species. 



Helderberg formation, Cumberland. 



3. A longitudinal section of a specimen, the septa being proportionally 



a little more distant. Coeymans formation, New York. 



Fig. 4. OKTHOCERAS SCHUCHERTI Maynard n. sp 487 



Internal cast. Helderberg formation, Keyser member, Cumberland. 



Fig. 5. ORTHOCERAS RIGIDUM Hall ? 488 



Fragment preserving surface ornamentation. Helderberg formation, 

 Keyser member, Devil's Backbone. 



Fig. 6. CYRTOCERAS ? DUBIUM Swartz n. sp 488 



Internal cast of type. Helderberg formation, Coeymans member, 

 Devil's Backbone. 



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