Nothing is more curious in. nature than the persevering efforts made by the living principle in plants 
to force their radicle downwards; whatever efforts may be made to give it another direction, are constantly | 
baffled by the growing power, which knows where its nutrition lies, and will go rightly to seek it. No ; 
animal can display a more persisting volition. Yet when circumstances become such, that its food is not ! 
downwards, but upwards, it will then, and then only, rest in that inverted and ascending position. Earth 
is not so essential to vegetable growth as moisture; for even trees will grow in water only. Earth is but 
the bed in which the vegetable nutriment is best prepared and presented to the absorbing roots. 
When the plant develops in the fitting soil, the roots nourish it from below, and the leaves above con- 
tribute also their auxiliary supplies. Buds emerge in due time from the stem or branches, each of which t 
may be considered as a new vegetable, growing from its parent, but living in unseparating union with it, j 
yet only in close association, for it seeks its own independent nurture by its distinct, tho strictly combined j 
root. 
Plants with few and small leaves depend chiefly on the soil. Those with many and large ones, more 
on the atmosphere. But some can find nutriment, and grow, even from animals. Thus cryptogamic plants 
have been found vegetating on living wasps in the West Indies. This curious fact has been also noticed J 
elsewhere. They will even grow in the stomach of living animals; for several instances of this have oc- || 
curred, in which the force of vegetation has prevailed over the animal’s digestive power; at least, in those I 
who were entirely carnivorous. 
Warmth and moisture usually commence the process of germination as soon as they concur to the j 
seed: but if the due means for the further nutriment do not accompany the growth, the process stops, and 
the plant soon dies. Some vegetables — the parasitic tribes — fasten on a larger plant or tree, and fixing in 
that their roots, derive food from its nutritive juices. The living principle exerts itself with singular force 
and apparent judgment in searching for its nutrition when the ordinary sources and supply of it fail. The 1 
main fluid in vegetables is the sap. 4 It is really the blood of the plant, by which the whole body is nou- 
rished, and from which the peculiar secretions are made. 5 
Vegetables are not generally affected by the narcotic poisons, but they will absorb arsenic by their 
vessels and cellular tissues. Iodine facilitates the germination of seeds much more than chlorine, if they 
be watered with a solution of it: even those which have apparently lost all vital power, may frequently be 
made to germinate by Iodine. 
Light represses the evolution of the seed, but is essential to the production of the florification and 
fruit; yet, as if to show us that all things are but what they are specifically organized and actuated to be, 
and never are the chance productions of blind necessity, there is one plant which has been so formed as to - 
flower only in the dark — the night-flowering Cereus. But all such exceptions in nature are never casual, 
but always regularly arise from a peculiarity of structure, which is adapted to cause the particular result, and 
which is always constant in the species in which it occurs. Plants will germinate in rarefied air, but not 
rapidly. 
The parts of plants have a singular homogeneity, or sameness of nature and properties. Roots may 
be made to produce leaves, and buds of leaves may be transformed into buds of flowers. If a tree be 
inverted by planting it by the stalk, its roots then disclose leaves, and its branches send out roots. Plants 
grow most in the night and in cloudy weather: at noon, all increase is suspended. Between morning and 
noon, and noon and evening, it is but small. But flowers advance more in the day, and especially in the : 
meridian light and heat. Some plants and trees will continue to vegetate, tho overflooded by sea water. 
So tenacious of its vitality and power, their living principle is often found to be.* 
Turner’s Sacreil History. 
