THEORY OP THE EARTH. 121 



ibx inhabit all the climates from the torrid to the 

 frigid zone, we hardly find any other differences 

 among them, through the whole of that vast space, 

 than a little more or a little less beauty in their 

 furs. I have compared the skulls of foxes from 

 the most northern regions and from Egypt with 

 those of France, and found no differences but 

 what might naturally be expected in different in- 

 dividuals. The more savage animals, especially 

 those which are carnivorous, being confined with- 

 in narrower limits, vary still less ; and the only dif- 

 ference between the hyena of Persia and that of 

 Morocco, consists in a thicker or a thinner mane. 



Wild animals which subsist upon herbage feel 

 the influence of climate a little more extensively, 

 because there is added to it the influence of food, 

 both in regard to its abundance and its quality. 

 Thus the elephants of one forest are larger than 

 those of another ; their tusks also grow somewhat 

 longer in places where their food may happen to 

 be more favourable for the production of the sub- 

 stance of ivory. The same may take place in re- 

 gard to the horns of stags and rein-deer. But let us 

 examine two elephants the most dissimilar that 

 can be conceived, we shall not discover the small- 

 est difference in the number and articulations of 

 the bones, the structure of the teeth, &c. 



Besides, the species of herbivorous animals, in 

 their wild state, seem more restrained from migra* 



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