25G CONTRIBUTIONS TO 



The cells of the vascular bundle and of the epidermis 

 appear in this way to be less potentialized, — are as it were 

 cells of lower dignity than those of the parenchyma; and 

 perhaps this physiological peculiarity is connected with the 

 fact, that they more rarely secrete peculiar chemical substances, 

 but for the most part become thickened only by depositions 

 within their walls of new vegetable fibrous (or more correctly 

 membranous) substance. I cannot forbear venturing some 

 suggestions in this place, which are perhaps less closely con- 

 nected with the subject of this memoir, but which may possibly 

 at some future time be of importance for the understanding of 

 the entire plant. Let us recapitulate the process of growth of 

 the plant just now represented. A simple cell, the pollen-tube, 

 is its first foundation. Within this, cells are generated; in them 

 new cells are developed, and so forth, throughout the entire 

 life. But here the above-mentioned mode of the origin of the 

 vascular bundles and of the epidermis in relation to the paren- 

 chyma would indicate, that the lower the dignity of the cell, 

 the greater power does it possess, in the first place, of expand- 

 ing and extending in length, and the less capacity does it 

 possess, in the second place, of forming peculiar finer sub- 

 stances in its interior. If now the potentialization (poten- 

 zirung) of the cells proceed throughout the entire growth of 

 the plant, there thence results a constantly advancing approxi- 

 mation of organs otherwise kept asunder, and continually rising 

 ennoblement of the substances developed in the cells. Conse- 

 quently, the lower parts of the internodes will appear to be 

 more elongated than the upper ; the leaves and young shoots 

 {summitates herbarum, Pharmacol.) to contain nobler saps than 

 the stem ; the members become shortened as they approach 

 nearer to the upper terminal point of the plant, the leaves 

 come closer together, and the result of the continually 

 increasing potentialization of the cell, of the constantly dimi- 

 nishing expansion in length, of the constantly advancing ap- 

 proximation of the lateral organs, of the constantly rising 

 ennoblement of the substances developed, is, finally, the flower 

 in its individualised distinctness, with its splendour of colour, 

 its perfume, and its mysterious capacity of determining, by 

 means of its juices, a single cell to be developed afresh into an 

 independent plant, and to pass anew though the same cycle. 



