388 MB. M. p. PEICS ON THK VEGETATION OF 



Spruce and Pine, and everywhere the sub-arctic flora of northern Siberia 

 with Sphagnum and Vaccinium association was dominant. Progress in this 

 forest from the traveller's point o£ view was difficult and dangerous. 



On the slopes o£ the valleys with southern aspects the forests of Abies 

 sibirica and Pinvs sibirica appeared to be weaker in growth and were possibly 

 diminishing in area, for considerable forest fires had taken place here in 

 recent years. Where the fires had occurred I saw indications of dry steppe- 

 like flora, containing many types of Graminese accompanied by Aspen, Poplar, 

 and Birch, creeping in and competing with the Vaccinium association. In 

 addition to this there were certain places where the swamps appeared to be 

 in a state of partial desiccation with evidences of former mossy hummocks, 

 now dry and covered with grasses and species from the steppes further to 

 the north. 



The second series of observations were made after entering the Upper 

 Yenisei plateau by a low neck between two disconnected ridges of the 

 Sayansk system. We descended the valley to the Sisti Kem for some dis- 

 tance, but before its junction with the Bei Kem, turned east through the 

 Larch forests and followed up a side stream, called by the natives the 

 " Japsa," to its source in another isolated uplift called the Tashkel mountains. 

 Crossing from here to the watershed of the Shabash River, we followed this 

 down to its junction with the Kamsara River and finally reached the Upper 

 Bei Kem. A further expedition was made towards the head-waters of the 

 Bei Kem in the neighbourhood of Lake Todju Kul, after which a long 

 journey was made in a raft down the Bei Kem, past a series of rapids into 

 the steppes of the Ulu Kem and the Kemchik. 



In the upper regions of the Sisti Kem and Shabash Rivers, the valley 

 bottoms of which average about 3000 feet in altitude, we found forests of 

 Piniiis sibirica accompanied bv' sub-arctic flora, indicating cold conditions in 

 winter and a considerable rainfall in summer. This forest and association 

 also covered the mountains of tbe Tashkel. In the lower reaches, averaging 

 2000 feet in altitude, the forest consisted of Larix sibirica scattered in park- 

 like glades with natural meadows. The flora associated with this was of a 

 distinct type and might be called the '' Siberian Larch-Forest Association." 



In the Larch forest on the Japsa River I found Geutiana vei-na var. angu- 

 losa, Vaccinium Vitis-Idcea, Sjjireea sp., Potentilla frvticosa, and Erythronium 

 Dens-canis. 



On approaching the Tashkel mountains, forests of Finns sibirica and Abies 

 sibirica began to appear on the valley bottoms and reached up to the sides of 

 the mountains to 5000 feet. The ground flora here consisted of Bdula nana, 

 Vaccinium, Vitis-Idcea, RJiodedendron clirysanthum, Viola bijlora. In s« am]>y 

 areas there were large beds of Primula nivalis and of Trollius asiaticus and 

 Euphorbia lutescens. There appeared to be a succession of floral tvpes on 

 these Alpine meadows which changed as the summer advanced. Thus 



