THE NORTH TEMPERATE ZONE 



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poppy, and the little primrose, Primula farinosa. With these are 

 associated such distinctly American genera as Pentstemon and 

 Phlox. 



Northwestward, the western Rocky Mountains unite with the 

 northern Cordillera in Idaho, Washington and British Columbia; 

 and this accounts for the strong infusion of Pacific coast species in 

 the Rockies of Idaho and northern Montana. These are mostly 



Fig. 30. — Alpine vegetation, Glacier National Park; left, Alpine fir; right, false- 

 hellebore {Veratrum viride). 



absent from the southern Rocky Mountains, where the drier and 

 hotter climate is less suited to these northern moisture-loving 

 species. 



West of the main continental divide is the extensive plateau 

 region, the Great Basin, comprising most of Utah and Nevada, 

 and parts of Idaho, Oregon and Washington. This is a region of 

 arid steppes and broken mountain ranges, with light precipitation, 

 this being specially marked in the southern areas. 



