'^'l920*^] DUNN — PACIFIC COAST AMBYSTOMIDAE 59 



Batrachuperus sinensis. Ambystoma, in a broad sense, and 

 Rhyacotriton, have similar pre vomers, and dentition that varies 

 from that of Rhyacotriton olympicus and Ambystoma ensatum, 

 both of which rather resemble Ranodon, to the different con- 

 dition observed in Ambystoma tigrinum. In this species there is 

 a continuous, nearly straight, row of teeth across the roof of the 

 mouth. 



