126 THE TRANSFORMATIONS OF THE ANIMAL WORLD 



of land shells, the Melanopsis and the Iberus of the 

 Mediterranean regions, and the Achatinella of the 

 Sandwich Islands. Without multiplying these ex- 

 amples ad infinitum, I shall simply take a few facts 

 chosen from among animals of our European fauna : 

 the hares in the temperate zones of the north and 

 centre of France are always distinguished from the 

 hares in the south of Provence, and more generally 

 of all the Mediterranean countries, by their greater 

 size, longer and more abundant fur, long and hairy 

 ears, and darker colour, in which black, grey, and 

 white predominate over the reddish tints. These 

 differences are still more accentuated if from 

 Provence we pass over into Africa. Algerian hares 

 hardly exceed one-half the size of the great Euro- 

 pean hares, and are remarkable by their generally 

 light red coat. Finally, in the Saharian region hares 

 are very small in size and of a dun colour. Some 

 excellent observers have not hesitated to see 

 among these hares representatives of several species. 

 The northern type retains the Linnaean name of 

 Lepus timidus, while that of the south takes that, of 

 Lepus Mediterraneus. And, lastly, the dun-coloured 

 hares of the desert regions receive the new name of 

 Lepus isabellinus. Analogous specific distinctions 

 have been made, and for similar reasons, between 

 the foxes and the weasels of the north and south 

 of Europe ; they imply, as will be seen, a good deal 

 of personal opinion. Other naturalists, quite as 

 conscientious, do not admit these variations to 

 the rank of species, and simply count them as races 

 or local varieties. 



But it is to the study of the shells of Molluscs 



