THE JURASSIC PERIOD. 



65 



the belt marked as land in Fig. 346, lends further support to the con- 

 clusion that a land barrier separated the interior waters from those 

 of the Calif ornian coast. The identity of many species from the Upper 

 Jurassic beds of the Queen Charlotte Islands and from the Frazer 

 River in British Columbia, with those of the western interior, imply 

 either connection between these areas, or connection of both with 

 some point along the migratory routes which the marine life followed. 

 Whether this connection was direct through British Columbia, or 



Fig. 347. — A cliff of Jurassic rock, Ih miles west of Bluff City, Utah. 

 (Cross, U. S. Geol. Surv.) 



whether it was by way of Alaska, east of the Rockies, is unknown. 

 The similarity of the Upper Jurassic marine fossils of America and 

 of Russia, more fully set forth later, would be explained by either 

 of these connections; so also would the fact that a few of the species 

 of the Californian coast are identical with those of the Queen Charlotte 

 Islands. Either connection would call for an extension of the Jurassic 

 beds of Montana, Dakota, Wyoming, etc., to the north or northwest. 

 In spite of the fact that such extension has not been demonstrated, 



