Many animals doze by day and do their prowling and puttering around during the hours of darkness. Many of the starry eyed little lemurs of Madagascar are night foragers and science tells us that these gentle animals are unable to tell the difference between darkness and dull, red light. In the Bronx Zoo, their cages are lit with red lights during visiting hours and their human guests can see them busily occupied, just as they are during the darkness of night.

Each type of animal peers out at the world through his own special eyes and what he sees depends to a large extent upon how his eyes are made. The dewy eyes of the little mouse do not see anything very clearly while the sharp eyes of an eagle can pick out details a mile away. Lemurs and many other night time animals are dazzled by daylight and see with mor6 comfort after the sun has set.

Cats have wonderful eyes which can be adjusted to see in bright or dimmer light. Your eyes, too, have this wonderful quality, though not to such a large extent. Light, carrying an image of the scenery, passes through the pupil of your eye and falls on a small screen called the retina. The pupil is a small round hole, the black dot in the very center of your eye. When the light is dazzling bright, the pupil becomes smaller to keep some of it out. When the light is dim, or when you are in the dark and asleep, the pupil of each eye relaxes and becomes big.

The cat has a slit pupil, shaped like an almond, and a pupil of this kind can close tighter than a round pupil. In bright sunlight, the pupils of Miss Kitty's eyes close tight and become thin lines.

In a dim light, her black pupils open almost wide enough to fill her entire eyes. By so doing, her eyes gather up as much of the scarce light as possible.

She has still another trick for improving her night vision. Behind the retina of the eye she has a thin layer of glassy cells which acts like a reflector button. Light passes through the retina and back again. In the picture she sees, the light areas become lighter and the dark areas become darker. However, this reflector button also shines out into the world   it is the eerie eye shine which glows in the dusky shadows.

The slit pupil and the special eye shine add to Miss Kitty's night vision, but she cannot see in total darkness where there is no light at all. Her wonderful eyes merely have a couple of tricks for making the best of dim light.

 The eyes of dogs and owls, raccoons and opossums also glow with eyeshine in the dark. This trick helps them make the best of the dim light. The owl, like the cat, has a slit pupil, though he cannot see nearly as well as she does in the daylight. He is, however, one of the few animals who can wink   he can open one eye at a time. But neither he nor any animal can see in total darkness.