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RATTLE-SNAKE. 



CHAPTER II 



The Animals of the United States 



The United States area, bordered by Canada on the north and by the acute angle 

 of the Mexican highlands on the south, may be divided into four zones succeeding 

 each other from east to west. In the first or Atlantic zone there is a copious rain- 

 fall at all seasons and the moist climate produces extensive forests. The second 

 zone, which occupies the area between the first and the foot of the Rocky 

 Mountains, has dry winters and moist summers, vast plains being clothed with 

 grass in consequence of the moderate rainfall, while the cold winter with its 

 northerly winds and sharp frosts prevents the growth of trees. This zone, which 

 includes the prairies, is followed by the table-land between the Rocky Mountains 

 and the Sierra Nevada, which has very little rain at all seasons and least of all 

 in summer, and thus is largely desert, with a corresponding type of vegetation. 

 The fourth zone is formed by the Pacific slope of the Sierra Nevada and comprises 

 the States of Washington, Oregon, and California. The rains, which are abundant 

 in summer in the north, decrease in quantity as we pass from north to south, the 

 southern part of California being very poor in moisture. Accordingly, in central 

 California we find hard-leaved trees characteristic of a climate with moderate 

 moisture, while the abundant rains of the north give rise to rich forests of 

 deciduous trees. 



Corresponding to the more varied nature of its physical conditions, the area 

 of the United States has a richer fauna than that of Canada, and its animals bear 



a decidedly American stamp. 



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