32 



VEGETATION OF THE PEAK DISTRICT 



[CH. 



not to be regarded as a factor of importance in its relations to 

 the differential distribution of the plant associations within a 

 limited area, but rather as a factor which is fairly constant over 

 extensive districts. As a limiting factor, therefore, it only 

 becomes significant when different geographical or climatic 

 districts are under comparison. 



Velocity of the Wind 



