268 



HISTORICAL PALAEONTOLOGY. 



GENERALIZED SECTION OF THE CRETACEOUS SERIES 

 OF BRITAIN. 



Fig. 185. 



Eocene. 



White Chalk with Flints. 



- White Chalk without Flints. 



.. Chalk Marl. 



... Upper Greensand. 



~ Gault. 



Lower Greensand or 

 Neocomian. 



W r eald Clay. 



> ., Wealden Series. 



Hastings Sands. 



In North America, strata of Lower Cretaceous age are well 

 represented in Missouri, Wyoming, Utah, and in some other 

 areas ; but the greater portion of the American deposits of 

 this period are referable to the Upper Cretaceous. The rocks 



