FACTORS OF INCREASE lo: 



Provision for 



Other hand, checking growth by root pruning 

 or b\^ keeping plants in undersized pots, re- 

 ducing the general vitalit^v bv slow disease, 

 and depriving the plant of sufficient soil and 

 moisture, show a favoring action upon the 

 reproductive part in hastening and multiply- 

 ing the formation of flower and seed far in 

 excess of the development attained by the 

 vegetative part. 



As a factor to insure perpetuity this law is 

 evidently important in guarding against ex- 



i • i • r i 1 , ^. . x'rovision i 



termmation, for the poorer the conditions for perpetuity 

 growth, the more effort the organism puts 

 forth toward seed-bearing. One cannot fail 

 to be impressed by the thought, however, 

 that if this be a general law of nature, it 

 would seem to imply that the weakest and 

 least favored individuals, being most fruitful, 

 are most likely to be perpetuated, which is in 

 evident contradiction to the accepted theory 

 of natural selection and to common observa- 

 tion. 



There is, however, another factor which 

 comes into play here, as a corrective of this 

 tendenc\^ to deterioration of the race, and it 

 is to this law that special attention will now 

 be directed. 



In all the methods of increase in rate of 

 growth, so far brought forward, the change 

 has been due in the main to external agencies, 



