THE SURFACE OF THE GLOBE. 71 



material of ivory ; it is the same with rein-deer antl stags, according 

 to their woods ; but let us take the two most dissimilar elephants, and 

 we shall not discover the least differences in the number or articula- 

 tions of their bones, in the structure of their teeth, &c. 



Besides, the herbivorous species, in a wild state, appear more 

 limited in their dispersion than carnivorous animals, because the species 

 of the food unites with the temperature to confine them. 



Nature takes care to prevent any alteration of the species which 

 might result from their mixture, by the mutual aversion which she 

 has implanted within them. All the plans and the power of man are 

 called forth to effect these unions, even in the species most alike ; and 

 when the productions are fruitful, which is very rare, the fertility does 

 not last beyond a few generations, and would not probably take place 

 without a continuation of the cares which excited them. Thus, we 

 do not find in the wood intermediate individuals between the hare and 

 the ^rabbit, between the stag and the fallow deer, between the marten 

 and the pole-cat. 



But the sovereignty of man alters this order ; it developes all 

 the variations of which each species is capable, and derives from 

 the production what the species, left to themselves, would never have 

 done. 



Here the degree of variation is still proportioned to the influence of 

 their cause — which is slavery. It does not rank very high in the 

 domestic species ; as for instance, a cat. Hair of a finer texture, 

 brighter colours, size greater or less, is all that it proves, but the 

 skeleton of an Angora cat has no decided or perpetual difference from 

 that of a wild cat. 



From domesticated herbivorous animals, which we transport to 

 every kind of climate, which we accustom to every sort of food, and 

 to which we assign labour and nourishment without rule, we obtain 

 greater varieties, but still they are only superficial. A greater or 

 less height — horns longer or shorter, or even entirely wanting — a 

 lump of fat more or less developed on their shoulders — form the 

 difference of oxen; and these differences are for along time kept up, 

 even in those breeds exported from the country in which they were 

 produced, when proper care is taken to prevent crossing. 

 • Of this kind are the numerous varieties of sheep which are valuable 

 for their wool chiefly, because that is the object which has obtained 

 the greatest attention of mankind. It is still rather less, although 

 distinctly marked in horses. 



In general the forms of the bones vary but little ; their struc- 

 ture, their articulation, the' form of their large grinders never vary. 



