Flowers and their friends

by Margaret Warner Morley

There are many, many ways by which plants have changed their leaves and stems in order to protect themselves from being eaten, and all this came about very, very gradually.

While these things were happening, other things were happening too. Wherever there is life there is change. Living things keep changing all the time.

The little fern that drops from the leaf of its parent is, in a general way, like the parent, but it is not exactly like its parent; it is itself and has some peculiarities of its own. You see, it changes a little from the parent form or, as we say, varies. Every living thing has this power to vary within limits. No doubt, the power of variation was much greater in early times, and animals and plants were able to change much more then than now.

As time went on, things sort of settled down, as it were, and stopped changing so rapidly.

But way back in the early ages the plants changed a good deal. And all they had to work with, you will remember, was just stem and leaves,—not another thing. But that was enough. They could change stem and leaves into thorns, as we know, and they could do something else. They could change leaves into pistils.

When the leaves divided their work, some plants devoted certain of their leaves to the task of making new plants. Ferns show this up to this very day.

Look at a clump of ferns in the woods any time in the middle of the summer or later, and you will see that some of the fern leaves have little dark spots on their backs. Sometimes these dots are on their margins, sometimes on the ribs, and sometimes scattered everywhere over the back of the leaf.

These dots are little cups filled with a fine dust, which falls on the ground and finally gives rise to more ferns. It is sometimes called fern seed, but the bits of dust are not exactly seeds. In the end they answer the same purpose, however. Well, suppose one of these fern leaves with the dots growing on it should curl over backwards until its edges met, and suppose the little grains should become true seeds, then we would have a very good ovary with the ovules inside.

Fern leaves do not act in this way; they are too old-fashioned. But some of the leaves in flowering plants do. They just roll up into a pistil, with young plants, in the form of seeds, growing inside.

And to this day that is all a pistil is,—a leaf, or a whorl or circle of leaves, rolled together, with seeds growing along the inner part. Of course, in time, these pistil leaves changed very much, and to-day we find all sorts of pistils, and by just looking at them, we would never suspect they were leaves or ever had been. And they are not leaves any more, and they themselves never have been leaves; but long ago the pistils of their ancestors were leaves or parts of leaves, and they have inherited and improved upon these pistil leaves, as a boy improves upon a willow twig and makes it into a beautiful carved whistle that does not look at all like a willow twig, and yet that is just what it is at heart. So you see, one of the most important parts of the flower is, after all, “nothing but leaves.”