6 INHERITANCE. Chap. XIII. 



vvhetlier or not there has been any close degree of reversion. 

 It is not known in any instance what variety was first turned 

 out ; several varieties have probably in some cases run wild, 

 and their crossing alone would tend to obliterate their proper 

 character. Our domesticated animals and plants, when they 

 run wild, must alwaj^s be exposed to new conditions of life, 

 for, as Mr. Wallace ^^ has well remarked, they have to obtain 

 their own food, and are exposed to competition with the native 

 productions. Under these circumstances, if our domesticated 

 animals did not undergo change of some kind, the result 

 would be quite opposed to the conclusions arrived at in this 

 work. Nevertheless, I do not doubt that the simple fact 

 of animals and plants becoming feral, does cause some 

 tendency to reversion to the primitive state ; though this 

 tendency has been much exaggerated by some authors. 



I will briefly run tlu'ougli the recorded cases. With neither 

 horses nor cattle is the priinitive stock known; and it has been 

 shown in former chapters that they have assumed diiferent colours 

 in diifereut countries. Thus the horses which have run wild in 

 South America are generally brownish-bay, and in the East dun- 

 coloured ; their heads have become larger and coarser, and this 

 may be due to reversion. No careful description has been given of 

 the feral goat. Dogs which have run wild in various countries 

 have hardly anywhere assumed a uniform character; but, they are 

 probably descended from several domestic races, and aboriginally 

 from several distinct species. Feral cats, both in Europe and 

 La Plata, are regularly striped ; in some cases they have grown to 

 an unvisually large size, but do not differ from the domestic animal 

 in any other character. When variously-coloured tame rabbits 

 are turned out in Europe, they generally reacquire the colouring of 

 the wild animal ; there can be no doubt that this does really occur, 

 but we should remember that oddly-coloured and conspicuous 

 animals would suffer much from beasts of prey and from being 

 easily shot ; this at least was the opinion of a gentleman who tried 

 to stock his woods with a nearly white variety ; if thus destroyed, 

 they would be supplanted by, instead of being transformed into, 

 the common rabbit. We have seen that the feral rabbits of Jamaica, 

 and especially of Porto Santo, have assumed new colours and other 

 new characters. The best known case of reversion, and that on 

 which the widely spread belief in its universality apparently rests, 

 is that of pigs. These animals have run wild in tlie West Indies, 

 South America, and the Falkland Islands, and have everywhere 



*• See some excellent remarks on Proc, Linn. Soc.,' 1858, vol. iii. p. 60, 

 this subject by Mr. Wallace, ' Journal 



