260 HISTORICAL PALAONTOLOGY. 
GENERALISED SECTION OF THE CRETACEOUS SERIES 
OF BRITAIN. 
Eocene. 
White Chalk with Flints. 
Ee he ete ee ed Fe eer White Chalk without Flints. 
UpPER CRETACEOUS. 
= SS = = Chalk Marl. 
“es © Oe yi ie a wr ee 
eC eee aC eee Upper Greensand. 
Satta Gault. 
ee ee a eee Lower Greensand or Neo- 
Shs Ht Reece Marae raenteae comian. 
Weald Clay. 
LOWER CRETACEOUS. 
ea Wealden Series. 
=). ddastings 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 
of this series are mostly sands, clays, and limestones—Cha/k 
itself being unknown except in Western Arkansas. Amongst 
the sandy accumulations, one of the most important is the so- 
