GENERAL 



255 



and more; periods of rainfall and drought are more 

 sharply defined, and ranges of temperature, both in 

 seasonal averages and in absolute extremes, widen in- 

 creasingly. While the Scilly Isles, with their balmy 

 atmosphere, and mild winter and summer, express the 

 complete moderation of climate in their wealth of broad- 

 leaf, luxuriant evergreens, central Russia with a sharp 



Vegetation 



Tundra 



Coniferous fore 

 Deciduous trees 

 Mediterranean 



FIG. 101. Vegetation of Europe. 



and prolonged winter frost, and a scorching, dry, summer 

 heat, instances the opposite extreme in its steppe. In this 

 way may be distinguished an Atlantic or oceanic fringe, 

 a western European margin, a central European tract, 

 and an eastern European region. 



In respect of heat and cold and of their action on 

 vegetation, the western fringes, in conformity with the 



