134 



sists of coarse, stony sand which becomes covered by fine 

 desert-sand, as proved by numerous small dunes on the lee- 

 side of plants and in depressions. The wind bearing the sand 

 is burning hot as if from a fire. The temperature of the 

 air was 40 C., that of the surface of the sand 53 C. At 

 a distance the only plants discernible are large tufts of Ari- 

 stida pennata, widely scattered about 23 metres apart. 

 Coming nearer, the following plants are observed: Astra- 

 galus unifoliatus, a shrub less than a metre high with bun- 

 ches of crooked branches and small leaves; Reaumuria oxiana 

 a shrub up to 1 foot high with small white-spotted leaves 

 (salt-glands); the perfectly leafless shrubs of Ephedra alata 

 attain the height of 1 foot; Salsola subaphylla as shrubs of 

 about the same height looking very dry like sticks, and with 

 stiff hard leaves. Arthrophytum subulifolium is a transitional 

 form between a shrub and a perennial herb, its short green 

 branches with opposite acicular leaves occupy a short green 

 stem not 30 centimetres high, so that the plants resemble 

 miniature trees, the plant apparently striving to lift its assim- 

 ilation-shoots off the ground. The hairy leaf-rosettes of 

 Heliotropium sogdianum appear above the sand while its rhi- 

 zomes are subterranean. A few dwarfed specimens of the 

 perennial Zygophyllnm sp. are seen here. Agriophyllum lati- 

 folium and minus and Cornulaca Korschinskyi are dry, thorny 

 annual Chenopodiaceae already described. Associated with 

 these plants is Salsola sclerantha, hairy but thornless. 



In this locality with a stony subsoil, most of the plants 

 are dry or thorny, and no pronounced succulents occur. 

 Reaumuria oxiana seems to be the one which is most halo- 

 phytic in structure. 



12. Sand-desert at Ak-Rabat (right bank of the Amu 

 Darya). June 21. 1899. 



Almost level sand with small stones, no sand-drift and 

 no salts on the surface. In the lower, more sheltered parts 

 Alhagi Camelorum and Lycium ruthenicum occur, while Ari- 

 stida comes at higher levels. A low hill is covered with 

 Saxaul, mixed with Calligonum sp., Lycium, and Alhagi, very 

 similar to the vegetation seen at Chodsha Dawlet, but here 

 it is a spontaneous vegetation. A thick-stemmed Saxaul tree 



