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 ====V. Pigmy Plants and Their Wonderful Labors==== Next above the liver-wort, is a plant that will tell you how to find your way home if you ever get lost in the woods. One of the very first lessons a little Indian boy learned, when he went hunting, was that moss grows mostly on the north side of trees. It does that because the north side is damp and shady. If liver-wort is the child of the algae, or seaweed, moss is the grandchild and the fern the great-grandchild. They all like plenty of water, each one needing a little less water, and able to bear a little stronger sunlight. Each next higher plant learned new things. The liver-wort learned to grow leaves, to send down little sucker hairs and to fill spore cases. Let us see what moss learned to do.

Moss grows from a spore like the liver-wort. It nestles in any damp, shady spot it can find; on a porous rock or the bark of a tree, or on a soft bit of ground. At first it grows little strings of green cells, very much like its grandmother, the seaweed. These lie flat. They seem to be food cells for little brown rootlets that burrow into the soil, and for buds that rise in the air.

It doesn't matter at all which side of the moss-spore lies on the ground. The strings of food cells spread around it; the rootlets go down from the underside, and the buds rise from the upper. Neither the root nor the stem are in the spore at all, only cell material, whose business it is to get food from the earth and the air. The cells on the ground burrow for food, and the upper cells reach for it. The interesting part about moss is that the upper growth does not flatten into a leaf, that sprouts another leaf, like the liver-wort. It grows upward into a little stem, and leaves sprout from the stem. It grows upward, oh, quite a little bit of an inch, budding leaves all around the stem, and finally bears a little seed case on the tip.

Bravo! Don't you feel like clapping your hands? Think how long and hard those little yeast cells full of protoplasm had to work, before they could make the moss plant with a true root, a stem, a leaf and a seed case. But when it has done it moss is still such a tiny fairy plant, and so slender and delicate that it cannot stand alone. You always find the mosses crowded so closely together that they make green plush cushions. This is partly so that the little