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the germ, and perform the office of an umbilical chord. Without this supply of balmy liquor, the plant must inevitably have perished, its root being then too small to absorb a sufficiency of food, and its body too weak to assimilate it into nourishment.

Turnips, and all the tribe of cabbages in opposition to the leguminous and farinaceous plants, spread their seminal leaves upon the surface: these leaves contain all the oil of the seed, which, when diluted by the moisture of the atmosphere, forms an emulsion of the most nourishing quality; and, on account of its sweetness, the seminal leaves are greedily devoured by the fly. A grain of wheat, as soon as the germ has made its appearance, shows the milky liquor to the naked eye; but the umbilical chord, with its ramifications, can be discovered only by the assistance of the nicest glasses. As the plant increases in size, the balmy juice diminishes, till, at last, it is quite exhausted. The umbilical chord then dries up, and the external covering of the grain appears connected with the root in the form of a shrivelled bag. In the pro

All seeds have two coverings, which answer to the chorion and amnion in anatomy, and two lobes, or divisions, which perform the office of the placenta. These lobes constitute the body of the seed; and, in the farinaceous kinds, they are the flour of the grain. Innumerable small vessels run through the substance of the lobes, which, uniting as they approach the seminal plant, form a small chord to be inserted into the body of the grain. Through this the nutriment supplied by the placenta or lobes is conveyed for the preservation and increase of the embryo plant. Here it may be observed, that the lobes of farinaceous grains are fixed in the earth; they are, therefore, improperly termed seminal leaves, being rather the placenta or cotyledons of the plant. On the contrary, vegetables that have an oily seed, as rape, hemp, and turnip, carry their lobes upward, and spread them upon the surface in the form of broad leaves. These, though they perform the office of a placenta, are properly seminal leaves.

cess of vegetation, there is no mortality: from the moment that the seed is lodged in its parent earth, the vegetative principle begins its operations, and, in the whole successive gradation of them, illustrates the wisdom, the power, and the bounty of Providence. It is worthy of observation, moreover, that farinaceous vegetables and oviparous animals are nourished in their tender state nearly in the same manner. The embryo plant is supported by the farina melted down into a milky liquor, and conveyed into its body by means of an umbilical chord, at a time when the radicle was unable to supply a sufficiency of nutriment. An oviparous animal, from the time that it is brought into light, seems to receive all its nourishment from without; but this is in appearance only. The yolk of the egg, remaining entire during incubation, is received into the body of the animal, and, in a manner similar to the milky juice of the vegetable, is slowly conveyed into the vessels of the tender chick; and thus a sweet nourishment is prepared at a time, when neither the industry of the animal, nor the attention of its mother, could have procured a sufficient supply.

That the whole plant is contained in the seed, is an opinion as old as Empedocles; and it is still the prevailing doctrine among the generality of naturalists. Experience, the microscope, and the modern philosophy, give great countenance to it: for it is certain, that by the use of good microscopes, we discover, in the seed, several of the parts of the future plant, only in miniature; particula ly a little root called the radicle, and the stem called the plumule.

In the life of Malpighi, we have a debate between him and signor Triumphetti, provost of the physic garden at Rome, whether the whole plant be actually contained in the seed. The affirmative is

maintained by Malpighi, with cogent arguments; among which this is one, that in a kidney bean, before sown, the eye, assisted by the microscope, easily discovers leaves, a bud, and even the knots or implantations of the leaves on the stem. The stem itself also is very conspicuous, and plainly consists of woody fibres, and a series of little utricles. And Triumphetti having objected, that by poverty, transplantation, &c. several plants degenerated into others, particularly wheat into tares, and tares again into wheat; in answer to this, which is one of the strongest objections against that opinion, Malpighi replies, that he is not fully satisfied as to the truth of the objection; for that both he himself, and his friends, having made the experiment, no metamorphosis of the wheat succeeded; but, granting the metamorphosis, it is the soil, or the air, or the culture, that is in fault. Now, from a morbid and monstrous condition of Nature, there is no inferring her genuine and permanent state.

On this subject of seeds, there is one circumstance, which is too curious and remarkable to be passed over; namely, that in all countries, whether agriculture be promoted or neglected by mankind, Nature assists to sow and plant, as well as to fertilize the earth. The seeds of lofty trees are many of them winged; and, when they are ripe, the autumnal winds blow them off, and scatter them at a great distance from their mother plants. Others are in pods or husks, and not capable of being carried by the motion of the air; but Providence has given them as foods to birds, who carry them to distant places, and, in feeding, scatter part of the seed in soils proper for them to take root in and spring up. Even the droughts of the autumn contribute to increase and propagate trees and plants; for by causing deep chinks in the earth, the seeds of trees, and larger plants, that require depth, are lodged at pro

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per depths for their growth, and, at the same time, secured from such animals as feed upon them. Many of the seeds of annual plants are provided with a light down, by which they are enabled, with the help of the wind, to rise to great heights, and spread themselves very wide, to propagate their species in distant lands. The sun, by its annual visit to the northern and southern tropic, alternately gives action and rest to vegetation. The floods, which, in many countries, fall, at certain seasons, from the mountains, cover the plains, and enrich the soil by the sediment of their waters. The frosts of winter, also, by expanding the moisture contained in the earth, loosen and break the clods, so as to make them give way to the spreading roots of vegetables; and swine, moles, and such other animals, root up and loosen the earth, and fit it to receive the roots of plants.

Then spring the living herbs, profusely wild,
O'er all the deep-green earth, beyond the power
Of botanist to number up their tribes:
Whether he steals along the lonely dale,
In silent search; or through the forest rank,
With what the dull incurious weeds account,
Burst his blind way; or climbs the mountain rock,
Fired by the nodding verdure of its brow;
With such a liberal hand has nature flung

Their seeds abroad; blown them about in winds;
Innumerous mixed them with the nursing mould,
The moist'ning current, and prolific rain.

THOMSON.

Birds are natural planters of several sorts of wood and trees: they disseminate the kernels upon the earth, which, like nurseries, bring them forth till they grow up to their natural strength and perfection. Crows have been observed, at the latter end of autumn, planting a grove of oaks: they first made little holes in the ground with their bills, going about till the hole was deep enough, and then they dropped in the acorn, and covered it with the

earth and moss. Some think, that Providence has given the crows this instinct, solely for the propagation of trees: but others are of opinion, that it was given them principally for their own preservation, by hiding provision in time of plenty, in order to supply them in a time of scarcity; for it is observed, in tame pies and daws kept about houses, that they will hide their meat when they have plenty, and fetch it from their hiding-places when they want it. Such an instinct, therefore, in birds, may answer a double purpose, both their own support in times of need, and the propagation of the trees they plant; for, whenever they hide a great number of nuts or grain in the earth, we cannot suppose they find them all again, but that as many will remain in the plat of ground they make use of, as can well grow by one another. I shall add to this observation concerning the natural dispersion of seeds, that Providence has been amazingly bountiful in the wonderful increase of seed in many vegetables; insomuch, that with proper culture, the face of the whole earth might be covered, in a very few years, from the seed of a single plant.

No. XXX.

ON VARIOUS PHENOMENA IN THE VEGETABLE

KINGDOM.

Admiration, feeding at the eye,
And still unsated, dwells upon the theme.

COWPER.

THE vegetable kingdom, considered in various points of view, exhibits innumerable phenomena,

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