192 CHANGE OF SOIL AND VEGETATION. 



From the meridian of the western extremity of 

 the Munni-ula, the character of the valley on the 

 southern shore of the Hoanof-ho as we ascend the 

 River changes a good deal. The soil, which was 

 heretofore dense and fertile, is now mixed with salt, 

 so thick in some places as to cover the ground with 

 a white layer ; there are none of those marshes or 

 rivulets which are occasionally seen in the preced- 

 ing section, and, except in the great river itself, not 

 a drop of water can be found. 



As the soil changes so does the vegetation. The 

 flowery fields ' disappear, and in their stead the reed 

 grass {Calmnagrostis sp.), and Lasiagrostis splendens 

 cover the valley. The latter grows in tufts as high 

 as seven feet, and is so tough and wiry as to make it 

 difficult to pluck a single stalk. Clumps of bushes 

 become more frequent, often covering extensive areas 

 along the banks of the Hoang-ho.^ The prevailing 

 kind of shrub is a species of tamarisk, which is some- 

 times as high as twenty feet, with a stem three or 

 four inches thick. 



The sand-drift which in the former section was 

 12 to 15 miles from the bank of the Hoang-ho, now 

 approaches nearer and throws out occasional arms to 

 the River itself. These sands, as we have said, are 

 called by the Mongols KiiziipcJii — a name which 



^ In the valley of the Hoang-ho and the oases in the sands of 

 Kuzupchi, we gathered, between the middle of July and end of August, 

 1 37 kinds of flowering plants ; in the mountains of Munni-ula, between 

 the end of June and beginning of July, 163 kinds ; but some of the 

 latter were also found in the valley of the Yellow River. 



'^ These bushes also grow on the opposite shore of the Hoang-ho. 



