Peter Berry, age 11, of Shreveport, La, for his question:

WHAT IS A SHARK SUCKER?

A shark sucker is the common name of a fish that lives in all tropical seas and far out in the open oceans. The formal name of the fish is remora.

The remora has an odd sucker on the top of its head that looks like the sole of a rubber boot. This sucking organ is a modified first dorsal fin. The remora uses it to attach itself to the bodies of large fish such as sharks. Even though it is called a shark sucker, it has been found attached to barracuda, tarpon and other fishes, and even to large turtles and whales.

The remora is also known as an ocean "hitch hiker." The fish partakes of the food of its host.

The remora is two to three feet long, slender and flattened toward the head. A black band runs along the middle of its side and contrasts sharply with lighter shades above and below. Some have black and yellow colors.

The beau gregorys have bright blue heads and yellow tails. Some are striped vertically while others are striped lengthwise.