- 102 



Bassia sedifolia, Heliotropium Radula, Elymus sabulosns, Suceda 

 dendroides, Salsola sclerantha and other species of Salsola, Ce- 

 ratocarpus arenarius, Cressa cretica, Haplophyllnm sp., Arte- 

 misia, perennial Astragalus spp., and the species of Convol- 

 vulus already mentioned. What was said about Carex phy- 

 sodes under hummock-desert also holds good here, namely 

 that, although a spring-flowering plant, it plays a part during 

 summer in binding the sand by its rhizomes and roots. 



The vegetation of the desert of the sand-plains may be 

 comparatively dense (see fig. 16), but in other places, the 

 plants are much more scattered; the plain may indeed be so 

 bare that one must search for the plants. In spring, how- 

 ever, there is always a richer vegetation. 



The majority of the species are the same as in the other 

 forms of Sand-desert (sub-formations) and so are the growth- 

 forms. In addition to small shrubs, the following types of herbs 

 are found: thorny species (Alhagi, some species of Salsola, Cera- 

 tocarpus), hairy species (Goebelia, Kochia, Bassia, Heliotropium, 

 Salsola sclerantha, Artemisia, Convolvulus), the succulent spe- 

 cies are of minor importance (Su&da, Salsola). Most of the 

 species are perennials or undershrubs; the latter include 

 Kochia prostrata, Suwda dendroides (?), Artemisia and some 

 species of Convolvulus. Kochia stellaris, Bassia, species of Sal- 

 sola and Ceratocarpus are annual summer-plants. 



If a survey is made of the distribution of the growth- 

 forms, more especially that of the annual summer-plants of 

 the Sand-desert, it will be found that the annuals constitute 

 the majority of the plants in the Shifting-desert, and a much 

 smaller proportion in the Desert-plains. Of the herbaceous 

 plant-species given above for each sub-formation, 62 per ct. 

 in the shifting Sand-desert, 44 per ct. in the Hummock-desert 

 and 25 per ct. in the Desert-plains are annuals. Though no 

 very great importance can be attached to these figures owing 

 to incompleteness of the plant-lists, yet they have a certain 

 value because they confirm the results of direct observation. 

 The latter has taught me, that in the shifting desert such 

 herbaceous plants as are present are generally annuals, 



