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214 The green-bodied darner even ventures onto lawns, and eats house flies and mosquitoes there.

When dragon flies alight, which isn't often, for they seem tireless, they keep their wings outspread. The damsel flies fold their slender wings down their darning-needle backs, in the shyest way, as if they didn't want to be noticed. Their name comes from the French—demoiselle—which means young lady. One of the damselflies is so gray and modest that it is called marsh nun.

All these are insect feeders, both in the winged and in the larva stage. They lay their eggs on the water, or on the stems of water plants. The larva are not worms or grubs, but imperfect insects something like grasshoppers. They are called nymphs. But you will never see them. They live in the mud and on stems in the water, and they eat tadpole mosquitoes, and other water larva.

There is another insect something like the dragon fly that looks as if it might sting. It has a long, wire-like tail that it can curl over its back and poke into a hole in a tree. This is the ichneumon fly (ik-noo'mon). It often stands on the bark of a tree exactly like a woodpecker, so motionless that you can snapshot it with a kodak. It has very long, jointed legs and feelers, and one kind has a body that flares out behind like a brass horn. Some people think the ichneumon fly bores those holes in trees. But the hole is made by some boring beetle. At the bottom of each hole is a grub that feeds on the wood. The body of that soft, fat grub is just the place the ichneumon fly likes to lay an egg in. Then, when the baby hatches, it eats the grub. The fly will go all over a tree and poke its flexible wire egg-layer into countless holes. This clever creature eats very little, but spends most of its time laying eggs in the larva of moths, butterflies and beetles.

Sometimes you may see an insect that looks like a small dragon fly, but that flaps its four gauze wings, in flying. It lays eggs in tiny sand deserts in the woods, on river banks and sea shores. An innocent looking flier it is, but its larva is a true beast of prey—the cunning,