Marie Molnar, age 12, of Yorktown, Indiana, for her question:

Are snakes the only animals without eyelids?

In ancient days, the snake was a symbol of knowledge just as the owl was a symbol of wisdom. But our up to date scientists insist that the snake is not even a very sensible fellow. He knows only enough to cope with his snaky world. However, if he did happen to be smart enough to understand today's question, he would start an argu¬ment. He would insist that he does have eyelids. And what's more, our modern experts would agree with him. By eyelids, we mean coverings of skin or membrane to protect the delicate surface of the eyeballs. The snake has them. But they happen to be made of transparent membrane. His eyelids are sealed shut and he regards the world through glassy windows that protect his eyes from the jagged stones and scratchy grasses in his path.

The snake is not the only animal who has glassy eyelids of this type. The glassy looking eyes of fishes also are covered with eyelids of transparent membrane. Many other animals do not have skin type eyelids that open and shut as ours do. Some with eyelids of skin have the movable flap at the bottom. These fellows blink upwards instead of downwards.