486 THE CRETACEOUS PERIOD 



have been found in the Kootanie of the Northwest, or in the 

 Wealden of northern Europe, but they occur in the Lower Cre- 

 taceous of Portugal. In the latter part of the Lower and in all 



Fig. 160. — Sassafras dissectum, 1/2. Dakota stage. (Lesquereux.) 



the Upper Cretaceous, the flora assumes an almost completely 

 modern character, and nearly all of our common kinds of forest 

 trees are represented : Sassafras, Poplars, Willows, Oaks, Maples, 

 Elms, Beeches, Chestnuts, and very many others. A new element 

 is the Monocotyledonous group of Palms, which speedily assume 



