physiologicallii considered. 597 



scription : the seed-grains entirely fill the place of seeds; all 

 possess vitality, and the Lunularia vulgaris, so common in 

 German gardens, propagates itself only in this way. In lichens 

 they often burst in astonishing numbers from the leaves, so that 

 the whole surface of the leaf appears to be covered with a gra- 

 nulated powder ; and the plants on which this takes place to a 

 great extent scarcely ever seed. 



Some time ago, an often mooted subject was again brought 

 forward in these pages, namely, the possibility of the develope- 

 ment of sound seed without fructification. The fact, as men- 

 tioned by M. Bernhardi, cannot be doubted ; the more so, as it 

 appears to me, from what has been said, that such a form of 

 seed, the construction of which may be something between 

 a seed-bulb and a tuber, is possible. 



The rudiments of the bud, when they begin to expand, dis- 

 play an independent individuality; not only in the cases we 

 have mentioned, but also when they are developed in any other 

 manner by metamorphosis or art. They show a striking 

 analogy to the seed-bulb, when they appear like little buds in 

 the axils of the leaves of some annual plants which do not 

 usually produce branches, as in Dentaria bulbifera ; and in 

 several species of Z>ilium, Begonm, and /Saxifraga, they appear 

 among the flowers ; or, as in some of the begonias, along the 

 whole of the stalk. Rudiments of buds on annual plants that 

 have done flowering may be made to germinate by artificial 

 means. For this purpose, the stalk is cut down to below the part 

 where it has flowered, and then put, like any other cutting, into 

 the ground. In moist and confined air, with the proper degree 

 of heat, these cuttings make no roots at the section in the 

 ground; but the latent buds in the axils of the leaves are 

 developed, and grow into young branches, throwing out at 

 their base a number of roots closely provided with hairs for 

 absorption, and thus become independent as soon as they are 

 developed. These young shoots are then taken off", and treated 

 as cuttings which have already rooted. In this manner, accord- 

 ing to my colleague Brauer's experiments, the red-flowered 

 LobehVe, Gloriosa superba, and several species of Phlox and 

 Dioscor^a, may be propagated very easily. Some lilies which 

 have no bulb-buds in the axils produce them when treated in 

 this way. 



Here may be mentioned, also, the buds which grow some- 

 times on leaves, or on the edges of leaves. The formation 

 of buds round the edges of the leaves of Bryophyllum, when 

 these leaves are laid with the under side on a pot full of moist 

 earth, is well known. The same phenomenon is less known in 

 the genera Kalanchbc, Echever/a, and Gloxinm ; and Echever/a 

 gibbiflora has this peculiarity, that the upper leaves possess the 



a Q 4 



