18 ON THE ORIGIN OF SPECIES 



to ducks and rabbits, the breeds of which differ con- 

 siderably from each other in structure, I do not doubt 

 that they have all descended from the common wild 

 duck and rabbit. 



The doctrine of the origin of our several domestic < 

 races from several aboriginal stocks, has been carried 

 to an absurd extreme by some authors. They believe' 

 that every race which breeds true, let the distinctive 

 characters be ever so slight, has had its wild prototype. 

 At this rate there must have existed at least a score of 

 species of wild cattle, as many sheep, and several goats 

 in Europe alone, and several even within Great Britain, j 

 One author believes that there formerly existed in 

 Great Britain eleven wild species of sheep peculiar to it. 

 When we bear in mind that Britain has now hardly one 

 peculiar mammal, and France but few distinct from 

 those of Germany and conversely, and so with Hungary, 

 Spain, etc. , but that each of these kingdoms possesses 

 several peculiar breeds of cattle, sheep, etc. , we must 

 admit that many domestic breeds have originated in 

 Europe ; for whence could they have been derived, as 

 these several countries do not possess a number of 

 peculiar species as distinct parent-stocks ? So it is in 

 India. Even in the case of the domestic dogs of the 

 whole world, which I fully admit have probably de- 

 scended from several wild species, I cannot doubt that 

 there has been an immense amount of inherited varia- 

 tion. Who can believe that animals closely resembling 

 the Italian ( greyhound, the bloodhound, the bull-dog, 

 or Blenheim spaniel, etc. — so unlike all wild Canidae 

 — ever existed freely in a state of nature ? It has often 

 been loosely said that all our races of dogs have been 

 produced by the crossing of a few aboriginal species ; 

 but by crossing we can only get forms in some degree 

 intermediate between their parents ; and if we account 

 for our several domestic races by this process, we must 

 admit the former existence of the most extreme forms, 

 as the Italian greyhound, bloodhound, bull-dog, etc., 

 in the wild state. Moreover, the possibility of making 

 distinct races by crossing has been greatly exaggerated. 





