176 GEOGRAPHICAL DISTRIBUTION OF ANIMALS. 



fauna and the climate. The tropical faunas contain a much 

 larger number of more perfect animals than those of the 

 temperate and polar regions. 



4th. There is a no less striking relation between the fauna 

 and flora, the limit of the former being oftentimes deter- 

 mined, so far as terrestrial animals are concerned, by the 

 extent of the latter. 



442. Animals are endowed with instincts and faculties 

 corresponding to the physical character of the countries 

 they inhabit, and which would be of no service to them 

 under other circumstances. The monkey, which is a 

 frugivorous animal, is organized for living on the trees 

 from which he obtains his food. The reindeer, on the 

 contrary, whose food consists of lichens, lives in cold 

 regions. The latter would be quite out of place in the 

 torrid zone, and the monkey would perish with hunger in 

 the polar regions. Animals which store up provisions are 

 all peculiar to temperate or cold climates. Their instincts 

 would be uncalled for in tropical regions, where the vege- 

 tation presents the herbivora with an abundant supply of 

 food at all times. 



443. However intimately allied the climate of a country 

 may be to the peculiar character of its fauna, we are not to 

 conclude that the one is the consequence of the other. 

 The differences which are observed between the animals of 

 different faunas are no more to be ascribed to the influences 

 of climate, than their organization is to the influence of the 

 physical forces of nature. If it were so, we should necessa- 

 rily find all animals precisely similar, when placed under 

 the same circumstances. We shall find, by the study of the 

 different groups in detail, that certain species, though very 

 nearly alike, are nevertheless distinct in two different faunas. 

 Between the animals of the temperate zone of Europe, and 

 those of the United States, there is similarity, but not iden- 



