III.] INDIVIDUALITY OF THE PHYTON. 85 



of Von Mohl upon the vegetable cell established a ra- 

 tional basis of morphology and physiology. 



What I wish now to show is that the evolution of the 

 vegetable kingdom cannot be properly understood until 

 we come to feel that the phyton, or each portion of the 

 plant which, when removed, has the capability of repro- 

 ducing itself and its parent, is in reality a potential 

 autonomy. In doing this, I shall not forget that the 

 plant also has an individuality as a whole; but as this 

 feature is quite aside from my argument, and is the 

 conception of the plant which is everywhere accepted, I 

 must necessarily confine my remarks to the individual 

 life of the phyton. The mere fact that the phyton may 

 reproduce itself is not the most important point to con- 

 sider, but, rather, that each part of the plant may re- 

 spond in a diiferent manner or degree to the effects of 

 environment and heredity. Before proceeding to this 

 matter, I should say that there is no doubt about the 

 capability of every plant to be propagated asexually. 

 It is true that all plants have not been so propagated, 

 but there is every reason to suppose that the gardener 

 can acquire the requisite skill to grow oaks and hickories 

 from cuttings were it worth his while to do so. (See, 

 also, page 70.) At present there are cheaper modes of 

 multiplying these plants. But certain pines and 

 spruces, which do not seed under cultivation, are prop- 

 agated by cuttings, and the tissue of these trees is as 

 little adapted to such use as that of any plants with 

 which I am acquainted. The fact that plants are not 

 grown from cuttings does not prove that they cannot 

 be so propagated, for we know that the essential struc- 

 ture of all of them is very similar, and that each node 

 and internode — or each phyton — does or may produce 



