6 INTRODUCTION [CHAP. 



that the conclusion drawn may be stated as 

 follows : The Origin of Variations in Structure 

 (upon which alone species are based) is due to 

 an inherent Power within the Plant, by means 

 of which it Responds to the Direct Action of 

 changed conditions of Life. The result being 

 what Darwin called "Definite" Adaptations. 



Darwinians say that the influence of the 

 environment may affect the " vegetative " organs 

 of plants, or the soma, but that anything so 

 " acquired " cannot affect the " reproductive " 

 germ-cells, and therefore cannot be hereditary. 

 Darwin himself maintained that such varia- 

 tions, on the contrary, are hereditary. His 

 words are : 



" With respect to what I have called the indirect 

 action of changed conditions, namely, through 

 the reproductive system being affected, we may 

 infer that variability is thus induced. Many 

 facts clearly show how eminently susceptible the 

 reproductive system is to very slight changes in 

 the surrounding conditions." * 



It must be remembered that no germ- or 

 sperm-cells are in existence in plants when the 

 environment acts upon their roots, stems or 

 leaves. Nevertheless the effects are hereditary, 

 as will be seen hereafter. 



Now there is an abundance of experimental 

 verification, and what may be called Nature's 

 own experiments which may be seen wherever 



1 " Origin of Species," etc., 6th ed. p. 7- 



