Eastman. — Mylostomid deutition. 



EXPLANATIOX OF PLATE. 



Upper pavement dentition of Mylostoma variabile Newberry, from the Cleveland 

 shale of Sheffield, Ohio. X i- a./J.p., anterior pair of palatoptery gold plates: 

 right (Amer. Mus. Nat. Hist., Cat. 43 G), le/l {idem, 42 G). p-p.p., posterior 

 palatopterygoid plates : right (Amer. Mus. Nat. Hist. Cat. 3591), left (Mas. 

 Comp. Zool. Cat. 1437). Specimens belonging to difiFerent individuals, rear- 

 ranged in their inferred natural position. 



