170 GEOGRAPHICAL DISTRIBUTION OF ANIMALS. 



fauna is further subdivided into several districts, which may 

 be regarded as so many zoological provinces, in each of 

 which there is a certain number of animals differing from 

 those in the others, though very closely allied. Temperate 

 America presents us with a striking example in this respect. 

 We have, on the one hand : 



1st. The fauna of the United States properly so called, 

 on this side of the Rocky Mountains. 



2d. The fauna of Oregon and California, beyond those 

 mountains. 



Though there are some animals which traverse the chain 

 of the Rocky Mountains, and are found in the prairies of 

 the Missouri as well as on the banks of the Columbia, as, 

 for example, the Rocky Mountain deer, (Antilope furci- 

 fer), yet if we regard the whole assemblage of animals, 

 they are found to differ entirely. Thus, the rodents, part 

 of the ruminants, the insects, and all the mollusks, belong 

 to distinct species. 



431. The faunas or zoological provinces of the Old World 

 which correspond to these are : 



1st. The fauna of Europe, which is very closely related 

 to that of the United States proper. 



2d. The fauna of Siberia, separated from the fauna of 

 Europe by the Ural Mountains. 



3d. The fauna of the great Asiatic table-land, which, from 

 what is as yet known of it, appears to be quite distinct. 



4th. The fauna of China and Japan, which is analogous 

 to that of Europe in the Birds, and to that of the United 

 States in the Reptiles as it is also in the flora. 



Lastly, it is in the temperate zone of the northern hemi- 

 sphere, that we meet with the most striking examples of 

 those local faunas which have been mentioned above. 

 Such, for example, is the fauna of the Caspian Sea, of the 

 steppes of Tartary, and of the Western prairies. 



