LIFE-ZONES 631 



highest tributaries of the Black Irtish in the Mongolian Altai. 

 Many other fur-bearing animals range as far south as the main 

 dividing-line between Siberian and Central Asian fauna, but no 

 farther ; although in some cases they turn up again, in sHghtly 

 modified forms, in the Tian Shan. 



The gazelle are typical of an arid climate, — such as Inner Asia 

 possesses, — and they are generally to be met with in the open 

 plains south of the main dividing-hne. In Mongoha, however, 

 a mountain — or rather a plateau — variety exists, and this gazelle 

 {Gazella gutturosa) extends its range northwards on to the high 

 steppes such as exist in Siberia at the head-waters of the Ob 

 River. The common gazelle of the region is the Goitred Gazelle 

 {Gazella suhgutturosa) and its allies, which have a wide range 

 from Western Asia to Mongolia. Bear are found wherever 

 there is sufficient forest-area, and wild-pig range over the entire 

 region both on plain and plateau ; of both these forms, however, 

 the Tian Shan zone produces slightly different varieties. Tiger 

 are met with only in the most southerly portion of the region, 

 and are of the small, thin-haired Central Asian type. The long- 

 haired Manchurian tiger does not range into the neighbourhood 

 of the Yenisei basin, which is the only portion of our region 

 which might be expected to hold it. Snow-leopards are to be 

 found on all mountain ranges as far north as the Turgun and 

 Altai. 



Of bird-life, there is not much to record, except regarding 

 the ranges of resident, non-migratory species, such as the game- 

 birds. From a collection of about 256 species, I scarcely found 

 a variety that I had not already collected in Russian Turkestan, 

 this alone showing how truly Central Asian is the fauna of Dzun- 

 garia. The distribution of the game-birds shows, however, certain 

 distinctive areas. The northern forests hold the capercailzie, 

 the black-cock, the hazel-grouse, and on the hill-tops the 

 ptarmigan. Of these only the black-game extend to the Tian 

 Shan, the ptarmigan reach to the northern part of the Mongolian 

 Altai, the capercailzie and hazel-grouse go no farther south- 

 wards than the Upper Yenisei basin. 



The dividing-line between the Tian Shan and Altai fauna 

 demarcates the northern limit of the Chukar partridge, but the 



