Suminar.v of tlie Floral C'tMiditioiis in tli(> Sa.vuiisk Mountains and 

 the rrjankai Country. 



After this gciicral view of tlic iKilural conditions of the region, as far as Ihey are 

 {■cnown, I will in llio following, soniewliai 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 heen til now. hroadly speaking, quite unknown. Tlieie may thus onh 

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



In its main features tlie terriloi v on jjolli sides, on the norliiern as well as on the 

 soutiuMu 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-ea.st of the mountains, on the large, comparatively 

 low-lying rock-stejipes about the L'lu-kem, bear a more .Mongolian stamp. Thus th.c 

 Sayan and the rrjankaicountry may be said to form a Iransilion oi- bondary zone 

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

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

 almost impenetrable coniferous forest. Owing to the fewness and short duration of mj 

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

 here into r.atuial 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 S u h a 1 p i n e Taiga o r F o r e s t 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-kcm. 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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