Peter Schneider, age 10, of Champaign, III,, for his question:

HOW LARGE IS A HEDGEHOG?

Hedgehog is the common name for a number of spiny, Old World mammals. Although superficially similar in appearance to the porcupine, the hedgehog is more closely related to the mole and shrew. The average hedgehog is about 10 inches in length.

Found in Europe, Asia and Africa, the hedgehog is characterized by a coat of long stiff, pointed spines on its back. The fur on its underside is soft. The color is dull, ranging from light tan in some species to black in others.

Hedgehogs have pointed snouts, small eyes, short legs and vestigial tails. The tails are imperfectly developed and have little or no utility.

When endangered, the hedgehog rolls itself into a ball by the action of several powerful muscles that arise from the head and neck on each side and loop around the rump. In this position its spines project in all directions.

Hedgehogs emerge at night from hedgerows to hunt the insects that consititute their chief food. They also eat worms, frogs, snakes, mice and birds eggs.

In July or August, the female hedgehog gives birth to from tour to eight young.