Plants or vegetables are organized substances, which live and grow by the aid of light, air, and moisture. They need to be fed as much as animals, and will as soon die without food, as an insect, bird, or quadruped. Instead of taking in their sustenance by means of a mouth, they suck it up by means of roots. These draw from the soil the particular nutriment that is required in the form of sap, and this is distributed to the branches and leaves of the plant. Heat and moisture are necessary in order to set the sap in motion. Air and light are imbibed by the leaves of the plants. The various colors of plants are drawn from the rays of the sun.
All plants are propagated by seeds. These, however minute, contain all the members of the parent plant—stalk, leaf and flower. These are so nicely folded up as not to be distinguished; but when the plant begins to grow, you can see, with the microscope, the several parts unfolding, one by one, until at last they assume the form of the plant from which they sprung. It is said that the acorn, which is the seed of the oak, contains all the members of the future tree.
Jack was exceedingly delighted with these curious facts, and, according to his custom, he pursued the investigation of the subject by his own observations, by reading books, and by inquiries of his intelligent and obliging aunt. In the progress of his studies, he learned many other curious facts, some of which we must relate, for they are quite amusing.
Although plants have no sense or thought, yet nature seems to have made provision which supplies all their wants. To prevent chestnuts and walnuts from being devoured before they are ripe, the former are covered with a prickly burr, and the latter with an exceedingly bitter rind. When these are ripe, the outer coating bursts open, and lets out the imprisoned fruit or seed. Similar contrivances are observed in respect to a multitude of other plants.
Some seeds, as those of apples, peaches, plums, pears, cherries, currants, &c., are covered up in a fleshy or pulpy substance, which we call fruit. Here a double purpose is answered. The seeds are nicely taken care of, while mankind, with many other creatures, are provided with an ample store of delicious food. But lest the seed should be destroyed before it is brought to maturity, the fruit is very sour or bitter, until the seeds are quite ripe.
Thus we see that God, who has taken such kind care of animals, by giving them the power and skill to acquire their food and perpetuate their existence, has also taken care even of the life and prosperity of plants. As these depend entirely upon seeds for their propagation, he has provided that these seeds shall be wrapped up, protected, and nursed, almost as carefully as little children. Nor is this all. We might suppose that a seed would fall from the tree, and finding no other soil than that beneath the shadow of its parent, it would shoot up and perish for the want of light, and heat, and air. But as children are able to go from the parent roof and find homes for themselves, so God has provided that seeds shall emigrate from their homes, and, scattering themselves abroad, cover the face of nature with diversified vegetation.
You will be curious to know how this emigration of the seeds is brought about. I will tell you. You have seen the thistle down, in the autumn, rise upon the air and go sailing along to a great distance. That down has got a thistle-seed attached to it, and it is carrying it along to some place where it may rest, and being imbedded by the rain in the soil, it will shoot up into a thistle. Thus you see the little seed is supplied with wings, upon which it flies away from home, and sets up for itself. One thistle will throw off many thousands of these downy seeds, and thus the race is multiplied.
There are many other plants that have winged seeds, which are distributed in the same way. Perhaps you think the rough winds of autumn are unpleasant and mischievous, but remember that they shake myriads of seeds from the plants and trees, and scatter them abroad over the land. Nor is this the only way in which seeds are disseminated. Birds carry the stones of cherries, and the seeds of various kinds of berries, from the place where they are produced, to other distant points.
Quadrupeds disperse the seeds of various grasses and grains, by carrying them from one point to another. The burdock and the cockle seeds attach themselves to the woolly fleece of animals, and are thus dispersed. Rains carry seeds down the slopes of hills and mountains, and rivers bear them from one region to another.
Some seeds scatter themselves by means of springs in their covering, furnished by the plant itself. If you slightly pinch the ripe seed-case of the pretty flower of the gardens called the balsam, it will burst asunder, and scatter the seed in all directions. The pouch which contains the seeds of the wood-sorrel, also bursts and scatters them around on all sides. The capsules of ferns open with a spring. The seeds of some species of this plant, when viewed through a microscope, upon paper, seem to be endowed with a kind of leaping movement.