WHAT IS EVOLVED I AT EVOLUTION? 2?$ 



before the individual comes into contact with external envi- 

 ronment, while it is out of reach, so to speak, of the contests 

 which are called struggle for existence. It is conceived that 

 there were in like manner in evolution intrinsic modifications 

 of internal structure, requiring for their functional operation 

 adjustments of the whole mechanism of the body, and that 

 these operations were relatively rapid, because they were the 

 expression of evolutional force working from within, and in 

 the determination of which the local and immediate conditions 

 of environment hand little or no part. As, for instance, in the 

 plant, the special modification of ordinary tissues to produce 

 the flower, and its complication of floral parts, relatively to 

 the life-history of the plant is rapid, and the opening of the 

 flower may in some sense be said to be occasioned by heat, 

 sunshine, or, in general, by external conditions; but in a 

 much more important sense it is true that the production of 

 the flower is intrinsic, and is determined by ancestral, pre- 

 existing conditions, and not by those present only at the time 

 of flowering. 



