Characters 1 5 1 



Siwalik deposits of India, where remains of the hitter are abundant. That 

 they have no intimate rehitionship with the oxen, may be considered tairly 

 certain ; and it seems more than doubtful if they have any very near 

 kinship with the musk-oxen, trom which they differ markedly in the 

 structure of the horns and in the form of the cannon-bones. Antelopes, so 

 far as our present knowledge goes, are among the oldest of the hollow- 

 horned ruminants, and since the gazelles and their allies have molar teeth 

 of the same general structure as those of the sheep, it is possible that 

 the latter may be a specialised offshoot from the ancestral stock of the 

 former. 



From the point of view of the systematic naturalist sheep form an 

 excessively difficult group to deal with. In the first place, several of the 

 local forms are so similar to one another that it is almost impossible to 

 decide whether they should be regarded as species or races. And, in the 

 second place, the more aberrant members of the group exhibit so many 

 characters common to the goats that it becomes a question whether, on the 

 one hand, it would not be advisable to include both sheep and goats in a 

 single genus, or whether, on the other, the sheep themselves might not be 

 divided into at least three genera. As a compromise, three distinct sub- 

 genera, or groups, of wild sheep are here recognised. In addition to these, 

 the various breeds of domestic sheep {Ov/s arics), which form the type of 

 the whole genus, are perhaps entitled to constitute a fourth and typical 

 group. Here it may be mentioned that the ancestral form of these 

 domestic breeds, which differ from all the wild species save the arui by 

 the length of the tail, is at present totally unknown, so that no detailed 

 mention of the typical group is made in the present work. The woolly 

 character of the pelage, which forms such a marked feature in the European 

 breeds of sheep, might seem another feature distinguishing all the domesti- 

 cated kinds from the wild species. This, however, is not the case, since 

 many of the domesticated breeds belonging to less civilised tribes, like 



