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WILD FLOWERS AND TREES OF COLORADO 



of low and high altitudes. Just as the plants of Louisiana are unlike 

 those of the Hudson's Bay country so we must expect the plants of 

 the plains to be different from those of the high mountains. The 

 climates are as different in the two cases. 



If a person sees a sulphur flower on the plains at Denver and then 



Fig. 16. — Canyon Vegetation 

 This steep-walled canyon is in the sedimentary rock area of the foothills. At the 

 left are willows and narrowleaf cottonwoods; to the right on the sloping canyon-sides are 

 junipers and cedars. Douglas spruces and rock pines are seen in the background. 



sees another plant with somewhat similar flowers on the top of Mt. 

 McClellan he may think that the two are merely forms of the same 

 species altered by the conditions. But this is not the case. They are 

 just as much separate things as are the polar bear and the common brown 

 bears of the temperate zone; just as different as the negro of Africa 



