Читать книгу Natural Wonders - Edwin Tenney Brewster - Страница 7

Table of Contents

The plant’s egg is, of course, the seed. We commonly say that the plant grows from the seed. And so it does. Yet this is not exactly true either, because the ripe seed is already a little plant, folded up tight and packed away in a hard case, like a chick inside its shell.

If one takes, for example, an ordinary bean or a peanut, peels off the shell and opens it carefully, it separates into two halves, held together by a little nodule at one end. These two halves, which together form pretty much the entire bean, are really two fat leaves. They are the yolk of the bean egg, on which the new bean plant is going to feed until it has grown leaves and root, so that it can pick up a living for itself out of the earth and air.

The rest of the new plant is the little nodule which lies between these seed-leaves. Curled up against the outside of the seed, like a puppy’s tail between its legs, is a short fat root; while hidden away between the seed-leaves is the next pair, tiny leaves almost too small to see, but real leaves nevertheless.

So the bean is an egg. Not a new-laid egg, but an egg with a little plant inside, all ready to hatch out and grow.

The bean egg changes to a bean plant.

If instead of cooking and eating the bean, we plant it in the ground, or in wet sawdust or blotting paper, it soon hatches out. The shell drops off, the seed-leaves first take in water and swell and then shrink away to nothing as the growing plant eats them up. The little root grows down, the little leaves grow up, the whole plant turns green and begins to climb the bean pole.

All seeds, then, are eggs just ready for hatching. They are like fish eggs, however, rather than like birds’ eggs, because the little fish and the little plant both save most of their yolk to use in getting a start in the world after they are hatched out. But the birds, you will recall, because they have large eggs and plenty of room inside, keep on growing till the yolk is all gone, and then hatch.

The little plant, as you might expect, gets inside its seed almost exactly as the little bird or frog or fish gets inside its egg. The “string beans” which we eat in the summer are fat pods stuffed out with bean-stuff to be used in making seeds. There are tiny beans inside, which are new-laid bean eggs, and so have no little plant inside, but only bean-stuff. The little bean plant, starting from nothing, forms one part after another, like chick and fish.

But where does the egg come from in the first place? The bean egg forms in the pod, too small at first to be seen at all, and keeps growing until it is big enough to begin to form the new plant. In exactly the same way, the mother fish, and the mother frog, and the hen, have a sort of pod inside them. First this pod stuffs and fattens itself out with egg-stuff, like a string bean. Then some of it turns into little eggs, too small to be seen. These grow and grow, like the beans in the pod, while the pod shrinks away. Only after they have grown a great deal, do they begin to form little beans, or fish or chicks inside.

Seeds that have Plumes and Wings

First of all, in short, the bean pod begins as a minute speck and grows into a proper pod. Then the bean inside this pod begins as a minute speck, and grows into a proper bean. Then the new bean plant inside this bean begins as a minute speck and grows into a proper bean plant, ready to be hatched out and shift for itself. So part of the mother plant becomes pod, and part of the pod becomes bean, and part of the bean becomes little growing plant. So it is with little fishes and little birds and little rabbits and puppies and kittens and all the rest of the little animals that you know.