202 MOSTLY MAMMALS 



many parts of Europe the wolf-dogs and sheep-dogs are 

 remarkably like the races of wolves inhabiting the same 

 districts ; and the black Florida wolf-dog is strikingly similar 

 to the black wolf of that country. Sheep-dogs may there- 

 fore be included among the breeds descended from wolves, 

 and are some of those which have undergone the least 

 amount of modification from the parent type. On the 

 other hand, when we proceed to South-Eastern Europe 

 and the South of Asia, we meet with breeds of dogs so 

 like the jackals of the same districts that it is hard to 

 believe they are not very closely related. South Africa 

 is the home of that very peculiar species, the black-backed 

 jackal, and in many districts dogs are met with showing 

 a marked resemblance in form and coloration to that 

 species, although having lost the deep black patch on the 

 back from which it takes its name. It has also been 

 noticed that certain domesticated breeds in South America 

 are so like the Cant's azarae of the same region as to lead 

 to the belief that the one is the descendant of the other. 



From these and other considerations Darwin was led to 

 the following conclusion: "It is highly probable that the 

 domestic dogs of the world are descended from two well- 

 defined species of wolf — namely, C. lupus and C. la trans — 

 and from two or three doubtful species — namely, the 

 European, Indian, and North African wolves ; from at 

 least one or two South American canine species ; from 

 several races or species of jackal ; and perhaps from one 

 or more extinct species." 



In all the above-mentioned instances the domesticated 

 breeds belong either to half-savage races, or are those 

 which, like wolf-dogs, sheep-dogs, and pariah dogs, have 

 departed but little from the original wolf or jackal type. 

 In some cases we have seen these breeds are kept true 



