132 GEOGRAPHICAL DISTRIBUTION. 



to the degree of heat or cold. The exceptions to 

 this rule, he farther observes, are easy to be ap- 

 preciated, and confirm its truth, since the moun- 

 tains, the various elevations and depressions of 

 the country, which even under the same parallel 

 modify the ordinary temperature, produce vege- 

 tables, and often animals, analogous to their 

 several degrees of heat or cold. The lofty moun- 

 tains in tropical countries, exhibit from their base 

 to their snow-clad summits, the same gradation 

 as these hemispheres present in going from the 

 equator towards the poles. 



The majority, however, of animals do not 

 ascend such heights, but seek their subsistence 

 in the plains, and less elevated regions ; yet here 

 a considerable difference obtains according to 

 the nature of the soil and country. The vast 

 sandy desarts of Africa and Asia, the Steppes of 

 Tartary, the Llanos and Pampas of South Ame- 

 rica have their peculiar population ; in the for- 

 mer the camel, and his master the Arab, whose 

 great wealth he constitutes, are indigenous ; in 

 the latter the horse and the Tartar who rides and 

 eats him ; or the Hispano- American, and the 

 herds of horses and oxen, returned to their wild 

 and primitive type, who snares them with his 

 lasso, and reduces them again to the yoke of man. 

 Numerous also are the peculiar animal produc- 

 tions to which different soils afford subsistence. 

 The sea-shore, sandy and barren wastes, woods 



