Summary of tlie Floral Conditions in the Sayansk Mountains and 

 tiie Urjanliai Country. 



After this general view of the natural conditions of the region, as far as they are 

 known, I will in the following, somewhat more closely, treat upon its vegetation. I 

 only aim to draw the main lines and give a first rough survey of the flora of these 

 tracts, having been til now, broadly speaking, quite unknown. There may thus only 

 be laid a basis for future and more minute treatments of the floral conditions here. 



In its main features the territory on both sides, on the northern as well as on the 

 southern side of the Sayansk mountains aie dry steppe regions, those to the north — as 

 already borne out — with a common Siberian stamp, and in the transition zone between 

 the steppe and the primeval forest with a vegetation having a distinctly boreal character, 

 whereas the scenery south and south-east of the mountains, on the large, comparatively 

 low-lying rock-steppes about the Ulu-kem, bear a more Mongolian stamp. Thus the 

 Sayan and the Urjankai country may be said to form a transition or bondary zone 

 between Siberian and Mongolian scenery. The Sayansk mountains proper, on the other 

 hand, are moist, and up to a height of 1800 — 1900 m. above sea-level covered by dense, 

 almost impenetrable coniferous forest. Owing to the fewness and tihort duration of my 

 investigations, I have not been able to make any attempt at classifying the vegetation 

 here into natural plant-societies. Only by way of suggestion I will mention that the 

 following 4 main regions may be distinguished in their leading features: 



1. The Subalpine Taiga or Forest Territory, comprising the Sibe- 

 rian north side as well as the Mongolian south side of the mountain masses, the flora 

 of which has a markedly subarctic character. 



2. The Alpine Region, comprising the loftier mountain tracts above the tree 

 limit (about 1800 — 1900 m. above sea-level), where arctic species of plants are 

 prevalent. 



3. The Lower Steppe Area about the Ulu-kem, mainly with a Mongolian 

 or central Asiatic stamp. 



Besides, it would be natural to separate here one floristic region more, viz. 



4. The Wooded Steppe Region, a transition zone between the lower 

 steppe areas and the subalpine taiga territory. 



As is the case on the north side of the mountains, this region also comprises 

 very large tracts in the Urjankai country, where especially occurring about the borders 

 between the more elevated and, accordingly, moister eruptives together with the wood- 

 lands and the lower and drier Devonian areas forming the steppes. Thus, in the Urjankai 

 country, these wooded steppes extend roughly from the Lower Sisti-kem southwards to 

 the Dora Steppe, and from the outfall of the river Ujuk to towards Bjelosarsk, on the 

 large Soyote Steppe, in the south-western part of the country, about the Ulu-kem. 

 Moreover, all over the borders between the primeval forest and the steppes in this 



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