370 Appendix B 



Organic Selection and Natural Selection 



" It has been said that organic selection is a sort of com- 

 promise between Weismannism and Lamarckism. It can, how- 

 ever, hardly be called a compromise. It abandons entirely the 

 Lamarckian position of the inheritance of acquired characters, 

 and that such agencies as use and disuse have any direct in- 

 fluence in producing variations which modify the offspring by 

 inheritance. The only Lamarckian feature that is left is, that 

 the environment, through the acquired characters it produces, 

 does have an important influence in guiding evolution. Such 

 a position is, however, perfectly in accordance with Weismann- 

 ism, as is shown by the fact that organic selection is endorsed 

 by Weismann. 1 At the same time, there is no doubt that it 

 quite materially alters the earlier notions of Natural Selection 

 and presents that theory in quite a different aspect. For it is 

 plain that with this idea the guiding force in evolution is no 

 longer simply the natural selection of minute, haphazard varia- 

 tions, as Darwin supposed, but a combined action of the in- 

 direct influence of acquired variations and the selection of hap- 

 hazard congenital variations. It has long been felt that the 

 theory of evolution by the selection of mere haphazard varia- 

 tions presents great difficulties, and, if it were possible to find 

 some more distinctively guiding force the gravest difficulties of 

 Natural Selection would disappear. It is for this reason that the 

 Lamarckians insist upon acquired variations as a guiding force, 

 and others claim that variations occur along definite lines. 

 This new factor of organic selection tries to show that acquired 

 variations, although not directly inherited, do furnish such 

 a guiding force, since they preserve the life of the individual by 

 adapting him to his new conditions, until a time, after many 

 generations perhaps, when some congenital variations of a 

 proper character appear. 



" If this factor of organic selection is admitted as a force, we 

 must ask how wide is its application. Is it a force like Natural 

 Selection, that will apply everywhere, or is it confined, as are the 



1 Professor Conn does not say v/here. J. M. B. 



