WILD SHEEP OF ASIA AND AMERICA 269 



rams of several of the races develop a voluminous 

 white ruff on the throat, which may disappear in 

 the summer coat. There is no dark flank-band 

 separating the fawn of the upper-parts from the 

 white of the belly, although there may be a blackish 

 patch behind the upper part of the fore-leg. The 

 summer coat, which is quite short, is always much 

 lighter than the thick winter one. In old rams 

 the horns are very large and massive, but dis- 

 play considerable racial variation in thickness and 

 direction ; the thickest and least expanded horns 

 occurring in the typical Altai argali and its imme- 

 diate relatives, and the thinnest and most outwardly 

 directed in Marco Polo's argali. In all cases the 

 transverse wrinkles of the horns are strongly deve- 

 loped, but there is considerable racial variation in 

 regard to the prominence of the outer front angle, 

 which in the Altai type is more or less completely 

 rounded off. 



The range of the species extends from Bokhara 

 in the west to Mongolia and Kamchatka in the 

 east. 



The various local races may be classified accord- 

 ing to the thickness and direction of the horns. 



Commencing with the races in which the horns 

 are of the thickest and most massive type, the first 

 on the list will be the Tibetan argali {O. ammon 

 hodgsoni), inhabiting the plateau of Tibet, from 

 northern Ladak to the districts north of Sikhim, 



