APPENDIX. 83 



of nature as always definite and not with Darwin as 

 indefinite, and meets the objection that modification 

 but not adaptation to outward conditions of life can be 

 inferred from this fact, by the bold assumption that it 

 is precisely the outward conditions of life or the en- 

 vironment which "induces the best fitted to arise." He 

 further concludes that natural selection has nothing to 

 do with the origin of species. At the basis of his 

 conviction lies the naturally correct view that the sum- 

 mation of accidental variations is insufficient for trans- 

 forming the species, but that definitely directed varia- 

 tion is necessary to this end. But concerning the way 

 in which external conditions are always able to produce 

 the fit variations, he can give us no information if I 

 am not mistaken, for the simple reason that such is not 

 the fact, that the outward conditions only apparently 

 determine the direction of variations whilst in truth it 

 is the adaptive requirement itself that produces the 

 useful direction of variation by means of selectional 

 processes within the germ. 



C. Lloyd Morgan also has recently expressed him- 

 self in favor of the necessity of definite variation, 

 though likewise without assigning a basis for its ac- 

 tion, and without being able to show how its efficacy 

 is compatible with the plain fact of adaptation to the 

 conditions of life. He seeks to find the origin of varia- 

 tion in "mechanical stresses and chemical or physical 

 influences," but this conception is too general to be 

 of much help. He has, in fact, not been able to aban- 

 don completely the heredity of acquired characters. 



Emery 1 likewise sees only the alternative of a "de- 



1 "Gedanken zur Descendenz- und Vererbungstheorie," 

 Biolog. Centralblatt, 1893, Vol. XIII., p. 397. 



