regions to study how the vegetation of the humid taiga must gradually give way to the 

 xerophilous steppe vegetation that advances in proportion as we get more and more south, 

 away from the higher mountains. Owing to the broiling sun the plants were mostly dry 

 and withered already in the middle of August when I visited these regions. About the 



Vegetation at 

 Ust Kainsara, 

 about 850 m. 

 above sea. 



Fig. 52. Typical scenery from tlie wouileU steppe region on ttie 

 Upper Bei-kem, near Ust Tarakcni. The trees are birch and larch. 



Kamsara. roughly 35 — 40 wersts south of Ust Sisti-kem, the taiga has completely dis- 

 appeared, the land farther to the south consisting wholly of steppes, alternating with 

 the open wooded steppes. 



On the Kamsara I collected a series of plants, on the whole indicative of a con- 

 siderably drier climate than farther north. On dry, open declivities the following plants, 

 particularly belonging to the steppe region, occurred: 



Caragana arboirscens, Rosa pi mpincUi folia. Spiraea hijpericifolia, Cotoneastei 

 melaiiocarpa, Dianlhus rhinensis, Sediim hybridiiin, Thymus Serpyllum, Dracocephaliim 

 nutans, Diacocephalum Ruyschiana, Phlomis tuberosa. Thermopsis lanceolata. Astragalus 

 fruticosus, Triticum crislatum, Poleniilla subacaulis. Fragaria collina. Peucedanum 

 baicalense, Galium verum, Galatella punctata, Artemisia sacrorum. Artemisia frigida. 

 Campanula glomerata. Origanum vulgare. Galeopsis Tetrahit. Plxleum Boemeri subspec. 

 decurtatum, Triticum caninum, Acnniium harbatum, Scabiosa ochroleuca. Cotyledon 

 spinosa, Atraphaxis frutescens, and Ephedra vulgaris. 



Growing especially in larch-forest: 



Aster alpinus. Polygonum undulatum irnr. alpinum, Chamaerhodos erecta, Potentilla 

 fruticosa, Rubus saxatilis. Solidago Virgaurea. Gentiana Aniarella. Euphorbia Esula. 

 Trisetum flauescens subpec. copiosnm nov. subspec, and Bromus inermis. 



82 



