Mary Powell, age nine, of Danville, Ohio, for her question:

ARE DEVIL'S DARNING NEEDLES USEFUL INSECTS?

Devil's darning needle is another name for the beautiful water insect, the dragonfly. It has four large, fragile wings which look like fine gauze. It is a very useful insect since it helps man by feeding on harmful insects such as mosquitoes.

Dragonflies are also sometimes called snake doctors, snake feeders, horse stingers and mule killers.

When the devil's darning needle flies, its wings shimmer and gleam in the sunlight. Its long, slender body is colored either green, blue or brown. Large compound eyes, which look like beads, cover most of the insect's head. It can see motionless objects almost six feet away and moving objects two or three times that distance.

The insect has six legs covered with spines. It can use its legs to perch on a limb, but it cannot walk. As if flies through the air, it holds its legs together to form a basket in which to capture insects. The dragonfly then grasps its prey with its legs or jaws and eats it while flying.

Dragonflies have been known to fly 50 to 60 miles an hour. They fly swiftly to escape from birds or other animals.