54 A MONTANE KAIN-FOREST. 



winter-deciduous habit, losing its leaves in October, not to renew them 

 until late February or early: March. 



Here, then, is a group of four north temperate deciduous trees which 

 have almost identical foliation and defoliation behavior when found in 

 their natural ranges, but exhibit considerable diversity when brought 

 into the climate of Cinchona. 



There is no locality on the globe which possesses a completely uni- 

 form climate throughout the year, and consequently no locality in 

 which vegetation fails to be subject to the influences of fluctuating 

 physical conditions. When the climate of the Blue Mountains is 

 contrasted with the climate of such a region as the eastern United 

 States it is made to seem uniform, in spite of its small annual fluctua- 

 tions. The vegetation of the eastern United States is correspondingly 

 marshaled into a unison of seasonal behavior, while the plants of the 

 Jamaican mountains show only a slight tendency to such a marshaling 

 (as indicated by the predominance of spring flowering and growth) in 

 accord with the slight changes of physical conditions from season to 

 season. In short, the more striking the differentiation of the two or 

 more seasons of the year in a given locaUty, the more striking is the 

 unison of vegetative and reproductive behavior in the vegetation; the 

 less pronounced the diversity of the seasons, the nearer does the vege- 

 tation approach the appearance of unbroken activity, an appearance 

 regarding which we still know little, and shall continue to know Uttle 

 until the entire subject of periodic phenomena is attacked by experi- 

 mental methods. 



