268 THE SHEEP AND ITS COUSINS 



tton with Dr. Duerst's view that the Kopet Dagh 

 urial is the ancestor of the turbary sheep of the 

 Prehistoric Swiss lake-dwellers, and that the Ladak 

 and Tibetan urial is probably the progenitor of the 

 domesticated sheep of those countries. 



The largest and finest of all the wild sheep is 

 the argali {^Ovis ammon) of Central Asia, typified 

 by the race inhabiting the Altai, but including a 

 number of more or less nearly allied races, such as 

 the magnificent Marco Polo's sheep of the Pamirs, 

 most of which were at one time classed as distinct 

 species. They show, however, such marked signs 

 of more or less complete intergradation, that it is 

 far preferable to regard them as local modifications 

 of a single widely spread and variable species, 

 although this renders its definition a matter of 

 some difficulty. Indeed, the limitations of some of 

 the local races are at present by no means properly 

 defined. 



Although its Bokharan representative is smaller, 

 and thus tends to connect the other races with the 

 Kopet Dagh urial, the argali is by far the largest 

 of the Asiatic wild sheep, or, indeed, of all wild 

 sheep, standing in some cases close on 4 feet at 

 the withers. It is also a paler sheep than the 

 urial, often showing a large amount of white on the 

 hind-quarters, which may extend in summer over 

 the greater part of the thighs, and having more 

 or less white on the muzzle, while in winter old 



