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weed from the water the hair-like cells will all fall together, so they look to be one narrow blade-like leaf. Every time the tide-water drops away and leaves seaweeds out in the air on rocks, the fronds fall and mat together.

After being left out a great many times, some of these frond cells learned to cling together, even when the waves washed back over them. The scattered strings of cells went into partnership and became a leaf. The clinging cells on the underside of the leaf grew into longer, stronger hairs to anchor the plant more firmly to the rock. They learned not only to cling, but to suck up water to feed the cells above. Then the little spore buds raised their heads, and tried to grow into something that would attend to the business of starting new plants better.

Liver-worts look much like very green lichens or very flat mosses, but they can easily be told from both. No lichen is so green and moist, and the smallest mosses have true sterns and roots. The liver-wort is just a mat of tiny, flat leaves. One leaf grows out of another, without a sign of a stem. The whole plant is just a thousand leafed mat. The upper side is the stem and leaf and flower, all in one. It is green, and can make food out of sunlight and rain and air. The lower side is white, and from it grows little thread-like, white hairs that act as anchor cables and water suckers. Every leaf that sprouts sends down its own little rootlets below, and grows spore cases on top.

Every part of this flat, mossy little liver-wort is so small that you will have to put it under a microscope to find out how wonderful and beautiful it is. You will find the leaves clearly marked; each a round, flat, green scale with curled up edges, and spotted with darker green. These spots are raised above the surface, and are of two different shapes; but you will never find both shapes on one leaf.

One of these spots looks like a tiny umbrella, upturned and fringed with spun-silk threads. Between the fringes peep little green cups or bottles with balls in them. They look as if they were waiting for something. They are. On the next leaf, perhaps, the raised spot looks like a toad stool with a star shaped top. It starts to grow from the under side of the leaf, curves around the edge, and suddenly stands up straight. On its flat top are little pocket holes.