288 EUROPE 



Central Europe. Under this name may be described 

 the region which includes the southern portion of Scandi- 

 navia, Denmark, and the bulk of the land east of the 

 lower Rhine valley, of the Vosges and Jura, and north 

 of the Alps : it stretches eastward in the shape of a 

 wedge, between the northern belt of conifers and the 

 Russian steppes, to the Urals. 



From the Atlantic coast eastward the rainfall de- 

 creases, while the contrast between winter and summer 

 temperatures increases. The trend of the winter iso- 

 therms lies in a north and south direction, and the 

 lines of equal duration of frosty weather are similarly 

 directed : for instance, the isotherm of 32* F. for January, 

 which marks the northern limit of average winter tem- 

 perature above freezing-point, runs from the west coast 

 of Denmark and Norway a very few points east of south 

 down to Trieste. Most of central Europe possesses over 

 two months of lasting frosts, but summers are warm 

 and the vegetative period is long and sufficiently damp, 

 the yearly amount of precipitation exceeding 20 inches. 



Those are ideal conditions for a dense forest growth of 

 a cool, temperate type, and it is well known that most of 

 central Europe was at one time heavily wooded. Deci- 

 duous trees with broad leaves are best adapted to this 

 kind of climate, and they occur in overwhelming majority; 

 yet the northern conifers are not excluded. Forests are 

 of a mixed type like those of eastern North America or 

 of Manchuria. Taking the broad lines of the respective 

 distribution of conifers and deciduous trees, the former 

 are characteristic of the upper slopes of the highlands, i. e. 

 of a climate analogous to that of northern Europe : their 

 occurrence in the lowlands, and under milder conditions, 

 generally marks outcrops of poor and dry soils, mostly 

 due to glacial or subglacial deposits, or again to a spon- 



