230 THE GENESIS AND MIGRATIONS OF PLANTS 



light on the Cretaceous and Eocene Floras of Alaska, which, from its high 

 northern latitude, affords a good parallel to Greenland. It would appear 

 that plant beds occur in that territory at two horizons. One of these 

 (Cape Beaufort), according to Lesquereux and Ward, holds species ot 

 Neocomian Age, and apparently equivalent to the Kootanie of British 

 Columbia and the Kome of Greenland. The other, which occurs at 

 several localities (Elukak, Port Graham, etc.), has a flora evidently of 

 Laramie (Eocene) age, equivalent to the " Miocene " of Heer and Les- 

 quereux, and to the Lignite Tertiary of Canada. The plants are accom- 

 panied by lignite, and evidently in sitn, and clearly prove harmony with 

 Greenland and British Columbia in two of the periods of high Arctic 

 temperature indicated above. 



