Certain forms of the sand-desert also have these two 
aspects, and one finds here in places a quickly fading Spring- 
vegetation; this is referred to in chap. 9. 
The spring-flowering period of the Clay-desert attains 
its richest and finest development at the foot of the moun- 
tains, for instance at the Persian Kopet Dagh and the western 
Thian-Shan. In such places the amount of water is greater 
than on the plains, and this causes in itself a richer vege- 
tation of spring-plants. Moreover there is often cultivated 
land at the foot of the mountains, and weeds from there 
along with plants from the neighbouring mountain slopes 
mix with the plants of the desert (KORSHINSKY see p. 36). 
Such deserts, rich in vegetation, TANFILJEW calls Loess- 
Desert-Steppe (the cxact term used is not easily translated 
from Russian!). “Semi-Desert” will be used to indicate them 
in the following account. 
A sketch of such an area has already been given (p. 44). 
In spring it certainly does not resemble a desert. Looking 
at the mass of flowers one obtains an overpowering impres- 
sion of richness, vigour and luxuriance. A closer examination, 
however, reveals traces of the desert nature. 
The plants do not form a close carpet or they do so 
only in patches, whereas in other places the soil is quite 
naked especially where salts crystallise out as a light dusty 
covering which gives the soil a greyish colour. Here and there 
among the fresh-green flowering plants one finds a grey Ar- 
femisia or an almost leafless low chenopodiaceous bush; 
they are still very backward in their development and one 
can see that their season is still to come. In a few places 
there are small stretches of moving-sands in the midst of 
the flower-decked area; these are bare or scantily covered 
with scattered coarse tufts of grass or low grey bushes. 
The following is a list of the plants which bloom during 
the spring in the Semi-desert, together with a short summary 
of the characters they have in common. 
Grasses are the principal constituents of the vegetation, 
and of these Poa bulbosa is by far the most dominant, that 
and the less important Hordeum secalinum are the only per- 
ennial grasses. The shoots of Poa bulbosa have, as is well 
