Kimberly Beaty, age 10, of Muncie, Indiana, for her question:

What is an archerfish?

This clever little fish can spit in a fly's eye from a distance of more than four feet. His aim is excellent, though the fish is under water and the fly up there in the air. The archerfish practices this remarkable skill because flying insects are his favorite food. As a rule, the victim falls plop into the water, where the sharpshooter can grab him for dinner.

The archer fish and his seven cousins live in parts of Southeast Asia, India and the Philippines. There the people watched and admired his remarkable antics for ages. But these reports did not reach European scientists until 1764. Then a description was read to the Royal Society of London. It claimed that this 7 inch fish can shoot a drop of water at a flying insect and brim him down for dinner. However, the learned scholars refused to believe such an unlikely nature story, especially since the specimen enclosed with the report was a well known butterfly fish, and not an archerfish at all. This packaging error caused a lot of fiery disputes through many years. Finally, experts went to Southeast Asia and proved the report to be true. But not until 1926 did American scientists prove how the archer fish shoots down his victims with a drop of water. He is an ordinary looking small fish, with no outside signs of his sharpshooting weapons. Some people call him the tiger fish because he has several black bands down his golden sides. When objects in the air are seen from under water, they appear twisted out of shape. The eyes of the archerfish are large, but show no sign that they can adjust to viewing above the surface.     The mystery of how he shoots his fast liquid bullets is revealed inside his mouth. He has a rather long loose tongue, which is smooth and very pliable along the sides and at the pointed tip. Along the roof of his mouth there is a long straight groove. When he arches his tongue to cover this groove, he has a sort of blowpipe through which to fire a shot.     There is plenty of watery ammunition around him, but the trick is shaping it into shootable pellets. He does this by slapping. his gill covers shut to force one or several drops of water into his throat. Teams of muscles in his mouth and tongue shape the bullets and fire them at high speed. The archerfish has very keen vision and constantly watches for insects sitting on the greenery or flying through the air. He rarely misses, though he may fire several quick shots to bring down his victim.

These remarkable sharpshooters are smarter than most fishes. When kept in aquariums, they seem to be aware of their admiring human audiences. It seems that practice makes perfect, for the old timers are the best performers. Young, archers watch and imitate the adults. A youngster only two inches long can spit about four inches    and miss his mark. But he keeps on practicing as he grows.