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EUROPE 



lichens, and higher up again they are more and more 

 interrupted by plantless rubble screes which ascend to 

 the snow-line. 



Northern Europe. The region of vast forests of 

 conifers includes most of Scandinavia, and Russia north 



FIG. 105. View in Southern Norway the typical 

 northern forest of Europe. 



of a line extending from the head of the Gulf of Finland 

 towards the mouth of the Vyatka. The exclusion of 

 summer-green broad-leaved forests seems to be deter- 

 mined largely by the shortness of the vegetative season 

 as marked by the correlative duration of continuous 

 frost which here averages five months. Of rainfall there 



