Mylostouiid uppcj- dental plates 

 I, 3 Imperfect left posterior palato-pterygoid plates of the type species of 

 Mylostoma (M. \- ar i a b i 1 e Newb. ) from the Cleveland shale of 

 Sheffield, O. 

 2 Left anterior palato-pterygoid plate of the same species, and from the 



same horizon and locality. 

 4 Right posterior palato-pterygoid plate of the same species, from same 

 horizon and locality, 

 5, 6 Right and left palato-pterygoid plates of D i n o m y 1 o s t o m a 

 beech eri Eastm. from the Portage shale of Mount Morris, N. Y. 

 7 Supposed vomerine tooth of an unidentified Arthrodire, from the 

 Cleveland shale of Ohio 

 All figures of natural size. Compare with reconstructions shown in 

 text figure i8, page 98, and text figure 31, page 150. 



