NORTHERN CHINA 27 



European type. This was to be expected from a region 

 with a severe and dry winter. When it is considered, 

 however, that northern China lies in the latitudes of 

 southern Spain and the Mediterranean, and is not a high 

 plateau, the importance of the severe winter as a con- 

 trolling influence upon the kind of vegetation is at once 

 realized. 



Lured at one time of year, and by a combination of 

 very favourable influences, into a growth of abnormal 

 luxuriance, vegetation is at another time compelled to 

 adjust itself to the eliminating conditions of a very try- 

 ing season : a strong rhythm, even more marked here 

 than in the coastal plains of eastern North America. It 

 is, therefore, natural that plant life in northern China, 

 unable through the winter limitations to assume a sub- 

 tropical aspect, should exhibit the northern cool, temperate 

 type in its highest activity. The vegetation of northern 

 China represents the supreme expression of the cool, 

 temperate, summer-green, broad-leaf, arborescent type, 

 and is to be compared with that of the southern Appala- 

 chians and the Atlantic coast-plains of North America. 



That the controlling feature of the climate upon vege- 

 tation is the severe cold weather is still further shown 

 by a comparison with the parts of Japan in the same 

 latitudes, which have a milder winter by reason of their 

 outlying situation, and are free from the cold and dry 

 northern winds from the desert. In southern Japan 

 we find the sub-tropical evergreen vegetation fully 

 developed; and, though of the broad-leaved, summer- 

 green kind, the plant life of northern China has distinct 

 relationship with more southern floras. The principal 

 trees are no longer oaks and beeches and others familiar 

 to us, but species of paulownia, catalpa, ailanthus, gle- 

 ditschia, sophora, and the paper-tree or broussonetia 



