26 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 8« 



The distinctness of the present form is indicated by the character 

 of the dentition. The great number of teeth (23) in the maxillary 

 series, their uniformity in shape and size, transversely compressed 

 crowns, and cutting edges angularly rounded anteroposteriorly dis- 

 tinguish this specimen from all other extinct North American lizards. 



In the regularity of size of the maxillary dentition, this specimen 

 resembles Prionosaurus regularis from the Lance of Wyoming, but 

 the more transversely compressed and spatulalike tooth crowns and 

 slightly larger size distinguish it. The name Paraprionosaurus 

 Wyoming ensis is therefore proposed for it. No clue of its family 

 relationships has been detected from this scanty specimen. 



U. S. GOVERNMENT PRINTING OFFICEi lOt 



