ANNALS CARNEGIE MUSEUM, Vol. IX. 



Plate VII 



Diploceras osborni Peterson. Type. No. 2S59. C. M. Cat. \'ert. Fois. X \. 



Superior dentition of Diplacodon elatitm Marsh. Type. Peabody Museum, Vale 

 University, Xo. 11. 180. X 3- 



