622 



ZONES AND REGIONS [Pt.III, Sect. II 



are rare and usually saline. ' The desert soil consists of shifting sand, clay 

 containing loess, silicious soil, either fine or gravelly in texture, and talus. 

 In the different parts one or other of the above-named materials pre- 

 dominates. The shifting sand is present chiefly in the south of the desert of 

 Gobi, by the river Tarim above the Alashan as far as the Ordos and up to 

 Dzungaria, therefore in the true basin of a former inland sea ; in the desert 

 it is only sporadic. Talus and flinty soil occur at the foot of the outlying 

 slopes of the mountains ; gravelly sand, mixed with quartz, agate, and 

 chalcedony, represents the most sterile parts of the desert (of common 



Ml 



fc2 



^ 



>& 







4& 



Fig. 356. From the desert of Gobi (West). Sand dunes with half-buried shrubs of Tamarix. 

 South Kashgar country between Cherchen and Nia. After Piertzow. 



occurrence in the Dzungarian tract). Finally loess-soil occurs usually in 

 union with shifting sand, talus, and gravel. In a pure condition or in the 

 form of saline marshes, it is only sporadic, and most frequent in the 

 southern, central, or western parts of the desert.' 



Przhevalsky 1 draws the following picture of the eastern Gobi (about 

 no E.): — 



' The surface of this steppe exhibits but little variety. The ground of 

 the Gobi in general is slightly undulating, although everywhere level tracts 



1 Pzchevalsky, II, p. 10. 



