PIIYTOGENESIS. 2 »9 



for instance, docs not always take place in such a manner that 

 the parent plant separates itself entirely from lluin, and scat- 

 ters them about singly, but it most frequently forms, previous 

 to its own individual death, a peculiar organ, which places the 

 offspring in a peculiar vital connexion with one another, and at 

 the same time serves as a reservoir for a certain quantity of 

 nutritive material, by which the first development of th< 

 young individuals is facilitated. But in mosl cas< a this organ 

 is merely a metamorphosis of some other one with which we 

 are already familiar, for example, the stem or the root, or, as 

 in the potato, the axillary buds; and no scientific person has 

 therefore ever hesitated to speak of these things as mere /tor- 

 tious of a plant, which continue to live as connecting member 

 between the younger individuals after the death of that one 

 which has generated them. On the other hand, a different 

 course has been taken, where stem and root simultaneously, and 

 therefore almost the entire totality of the plant, take part in 

 the formation ; and although the result in this case may per- 

 haps be that there can be no question at all of an hetero- 

 morphy of a known portion of a plant, still the physiological 

 identity in the signification of this and the former part has 

 not been maintained with precision, and the view has thus 

 been obscured. 



Most manuals are silent upon this subject, as though it 

 were quite self-evident that the tree was to be regarded as 

 the perfect plant j and I believe it not difficult to prove that, 

 where vegetable physiology still lies very deep in error, this par- 

 ticular misconception is solely in fault. Two entirely distinct 

 ideas have here been confounded, namely, the highest Btage of 

 development to which vegetable life can raise itself, ami the 

 type upon which the idea of the individual must be based. If, 

 then, the first of these ideas may be maintained with regard to 

 the tree, still the application of the second to it fails com- 

 pletely in every respect, as has been very correctly asserted 

 before by E. Meyer (Linmca, vii, p. 42 1). It necessarily per- 

 tains to the notion of a plant, that it produces foliaceous organs 

 on its stem, yet there is no tree which has leaves. Paradoxical 

 as this may sound, it is still not the Less true It is a feet, of 

 which certainly no botanist is ignorant, that no Lignified part 

 of a plant, even though it be only in its second year, is capable 



