LIFE 501 



Marine reptiles seem to have thriven on the western coast of 

 our country, especially in the middle and later Trias. The numer- 

 ous ichthyosaurs found in the later Triassic beds of this region 

 surest that it may have been a center of dispersion of these rep- 

 tiles. With the ichthyosaurs were other reptiles (thalattosaurs) 

 unknown elsewhere. 



