344 Appendix A 



increase in the size of the antlers has taken place, it does not 

 lead to the destruction of the animal in consequence of other 

 parts being unable to suit themselves to it. All parts of the 

 organism are in a certain degree variable {i.e. modificable), 

 and capable of being determined by the strength and nature 

 of the influences that affect them, and this capacity to respond 

 conformably to functional stimulus must be regarded as the 

 means which make possible the maintenance of a harmonious 

 coadaptation of parts in the course of the phyletic metamor- 

 phosis of a species. ... As the primary variations in the 

 phyletic metamorphosis occurred little by little, the secondary 

 adaptations would as a rule be able to keep pace with them.' 



" So far Professor Weismann. According to his conception, 

 variations of germinal origin occur from time to time. By its 

 innate plasticity the several parts of an organism implicated 

 by their association with the varying part are modified in 

 individual life in such a way that their modifications cooperate 

 with the germinal variation in producing an adaptation of 

 double origin, partly congenital, partly acquired. The organism 

 then waits, so to speak, for a further congenital variation, when 

 a like process of adaptation again occurs ; and thus race prog- 

 ress is effected by a series of successive variational steps, 

 assisted by a series of cooperating individual modifications. 



*' If now it could be shown that, although on selectionist prin- 

 ciples there is no transmission of modifications due to individual 

 plasticity, yet these modifications afford the conditions under 

 which variations of like nature are afforded an opportunity of 

 occurring and of making themselves felt in race progress, a far- 

 ther step would be taken toward a reconciliation of opposing 

 views. Such, it appears to me, may well be the case.^ 



" To explain the connection which may exist between modifica- 



1 In an article entitled 'A New Factor in Evolution,' published in the 

 American Naturalist for June and July, 1896, Professor Mark Baldwin has 

 given expression to views of like nature to those which are here developed. 

 And Professor Henry F. Osborn, in a paper read before the New York 

 Academy of Sciences, propounded a somewhat similar theory, but with, he 

 tells me, less stress upon the action of natural selection. 



