2бо TREES AND VEGETATION. 



former (at all events in the western side which we 

 explored), the range may be divided into three belts, 

 viz. the marginal, the tree-belt, and that of the 

 alpine meadow-land. 



The first of these, with the strip of undulating 

 plain belonging to it/ has an argillaceous soil studded 

 on the plain with boulders, and on the hills with 

 blocks of fallen rock. In this section the cliffs are 

 smaller and fewer in number than in the other two. 

 This marginal zone or skirt of the mountains is no- 

 where over a mile and a half in width. 



Here the only trees are occasional stunted 

 elms ; amongst the bushes we observed the yellow 

 briar [Rosa pimpinellifolid), the caragana, and an 

 occasional Ephedra, such as we had seen in Tsaidam, 

 at the foot of the northern slope of the Burkhan 

 Buddha ; nearer the mountains the commonest kinds 

 are the thorny convolvulus {ConvolvtUus tragacan- 

 thoides), and prickly astragalus {Oxytropis aciphylld). 

 The chief herbaceous plants are the thyme ( Thymus 

 serpylluni), Solomon's seal [Polygonatimi officinale), 

 Pegomim nigcllastriim (the last named belonged 

 exclusively to the plain), the onion, also growing on 

 the mountains as high as the alpine region, the 



* The belt of steppe, ten to thirteen miles wide, lying at the foot of 

 the western side of the Ala-shan range, is of a distinct character, dif- 

 fering from other parts of this country. Its surface is seamed with 

 deep gorges, and it has a general and in some places a very steep slope 

 from the mountains to the plain. Its soil is clay covered with shingle 

 or coarse sand, and studded with small fragments of fallen rock from 

 the neighbouring hills ; springs occur in parts of it, and the vegetation 

 is the same as that of the desert, with the addition of some mountain 

 plants. 



