438 CLASS MAMMALIA. 



fleetness soon leaves their pursuers at a distance, and they 

 can strike with the hinder feet with immense force, and 

 bite with great violence and effect. 



All the species of this genus are originally natives of 

 Asia and Africa. Three of them are aborigines of the 

 vast and elevated plains of central Asia ; the two last are 

 peculiar to the most southern regions of Africa. None 

 existed in America or New Holland previously to the dis- 

 covery of these countries by the Europeans, for we can no 

 longer regard the Huemul of Chili, described by Molina as 

 an Equus Bisulcus, or cloven-footed Horse. It is evidently 

 a ruminant animal of the genus of the Lama, if not the 

 Lama itself. 



The genus of the Horse and that of the Camel are the 

 only ones which have each of them furnished two domestic 

 species. These species will couple and produce. But not- 

 withstanding this circumstance, and notwithstanding all 

 the advantages afforded by domestication for the develop- 

 ment of certain parts, and the formation of varieties, these 

 species have never yet been converted into each other. 

 The individuals produced from this connexion remain al- 

 ways the same, and never reproduce. This fact is suffi- 

 cient to overturn the system of some naturalists, that the 

 diversity of species is owing to accidental causes, and that 

 nature did not originally establish a separate type for each. 

 It proves that this theory rests upon nothing but vague 

 conjecture, and has no well-authenticated phenomenon on 

 which to rest as a foundation. Conditions more favour- 

 able to the production of such a conversion of species are 

 not to be found in the whole Animal Kingdom, than are 

 afforded by the domestication of the Horse and Ass, and 

 the circumstance of their coupling. The physical differ- 

 ence between these two animals is trifling, and consists 

 merely in the proportions of a small number of their 

 organs. In their intellectual qualities they are more 



