Paddy Urlocker, age 8, of St. Catharines, Ontario, Canada, for his question:

What are bloodsuckers?

Bloodsuckers are wormy little wretches that live in streams and boggy swamps. Some people call them leeches and experts tell us that leeches are related to the friendly earthworms. The leech is a flattish worm, one to four inches long. Usually his color is muddy brown    and certainly he is not friendly. For he feeds by sucking blood from other animals, and even from people.

When you go wading in a stream or lake, a leech may attach himself to your bare skin. He has two suckers, one at each end. He uses his tail sucker to attach himself. Then he uses the sucker at his head end to make a hole in the skin and suck out a tummyful of blood. He gorges until he swells to three times his normal size. Then, as a rule, he lets go and does not need another meal for many months.