FOREST DISTItlBUTIOX AXD COMPOSITtOX. 



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siibarctic forest wliich extends across the continent. At the far north 

 it is characterized by the white spruce and aspen. The forest is 

 open, stunted, and of no economic value. 



Taking all the genera and species together, there is a far greater 

 variety in the eastern than in the western forests. A considerable 

 number of genera, perhaps a third of the total, grow within both 

 regions, but the species having continental range are few. They are 



