256 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 connected 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 parenchyma would indicate, that the lower the dignity of the cell, the greater power does it possess, in the first place, of expanding and extending in length, and the less capacity does it possess, in the second place, of forming peculiar finer substances in its interior. If now the potentialization (potenzirung) of the cells proceed throughout the entire growth of the plant, there thence results a constantly advancing approximation of organs otherwise kept as under, and continually rising ennoblement of the substances developed in the cells. Consequently, 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 diminishing expansion in length, of the constantly advancing approximation 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.
