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Dragonfly nymphs often live in water for a year or more. You will find them on the bottom of ponds or among plant stems along the edge of some quiet stream. As the nymph grows, wings are developing in the wing pads on the back of his thorax.
One day in spring or summer, when a dragonfly nymph is fully grown, he crawls out of the water and clings to a plant stem,
or perhaps a rock, above the water's edge. The nymph's exoskeleton splits open, and an adult dragonfly slowly pushes himself out into the sunshine. He spreads his wings, and, as they dry, beautiful colors appear in
them. Markings on the wings and bodies of dragonflies are usually red, green, or blue. Their enormous eyes are often the same
bright color as the spots on their wings. Because the dragonfly sees so well, he is a very good hunter, and difficult to catch.
When the adult finally emerges, its wings and exoskeleton are soft, as is the new ex-oskeleton of a crayfish or a caddis fly adult. As they dry, the wings and exoskeleton become hard and brittle.
You might never guess that a damselfly nymph is a close relative of dragonfly nymphs if you did not see that the damsel-fly nymph also has a large, folded under lip. You can always recognize these two nymphs if you turn them over and look at their lower lips. In the illustration, the folded lower lip of the damselfly can be plainly seen.
The young damselfly has a slender, graceful body. When you first see one of these nymphs, you will probably think that he has three broad tails. These are really tracheal gills. The "gill tails" are often brightly colored. The body of the damselfly nymph shown here was bright green, and the gills
were pale green with lines of darker green and brown.
Some damselfly nymphs develop and mature in a few weeks, but many of them live
all winter in ponds or streams. They swim through quiet water, or clamber over the stems of water plants. Like dragonfly nymphs, they feed upon other water animals. Fish, in their turn, eat a great many dragonfly and damselfly nymphs.
During the summer when you are exploring a pond, watch for adult dragonflies and damselflies emerging from their nymph skins. You will often find the empty exo-skeletons of nymphs clinging to plant stems or other surfaces, long after the adult insects have flown away.
Damselfly adults are brightly colored like their relatives, the dragonflies. They, too, have very large eyes, and feed upon flies, mosquitoes, and other insects in the air about them.
Female damselflies often lay their eggs in the leaves or stems of water plants. Some dragonflies also lay their eggs in plants. Other dragonflies fly low over the surface of a pond and dip the tips of their abdomens to lay their eggs in the water.
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