Birds' eyes are very different from ours. To begin with, they are round. Then they are placed one on each side of the head, so that they can look two ways at once. Owls are the only birds who have eyes turned forward like ours.

Birds' eyes also are of many colors. Besides our common black, brown, blue, and gray, birds have light and dark green, bright red, pale and deep yellow and orange, even white.

They have, like us, two eyelids. But while we use the upper one to close our eyes, most birds use the lower one. They have also a third eyelid, inside the others, a thin, white sort of skin, that moves across the eye from side to side, and is called the "nictitating membrane."

There are other ways in which birds' eyes differ from ours. The men who try to know exactly how birds are made have found out that birds' eyes make everything look much larger than it is, in other words, they are like magnifying glasses, or microscopes, so that a tiny insect egg, that we can hardly see, looks very big to a warbler.

Stranger still, when a bird is far off, his eyes are like telescopes. That is, when a hawk is soaring about far above the earth, he can see a mouse on the ground as well as if he had a telescope to look through. And the gulls who sail about over the shore, and follow steamers on sea voyages, can see small fish and tiny bits of bread thrown out by the passengers, even when they are lost to us in the foam made by the vessel.

Mr. Frank Bolles had a pet barred owl, and used to take him out with him. He says that the bird's sight was wonderful, better than his own aided by a strong glass. Many times the bird would see and watch a hawk so far off that Mr. Bolles with his glass could not see him until he came nearer, and then he looked no bigger than a dot against the sky.

There is a story told of some small birds migrating over the island of Heligoland, suddenly coming down in a flock on to a man's garden, and beginning at once to work among the leaves as if they were feeding.

The owner of the garden knew they did not eat leaves, so he shot a few and found them stuffed with small caterpillars. Then he looked at the plants and found many more caterpillars, each in the curled-up end of a leaf. The insects could not be seen, yet the birds, while flying over, no doubt saw the curled leaves and knew they were there.

Such eyes must be of great use in helping birds to find their food, and to avoid their enemies. But think what giants we must look to them! It is no wonder they are afraid of us.

Perhaps even more useful to a bird than his eyes are his ears, though they are so nicely covered up by the feathers that we cannot see them. The tufts of feathers that stand up on some owls' heads, and are called ears, are not ears at all, but merely decorations, like the crests of some birds and the long tail feathers of others.

But because they cannot be seen, we must not think birds have no ears; they have very good ones indeed. They can hear much better than we can.

Every one has seen a robin run over the grass and turn his head one side to listen. It is supposed that he hears the earthworm move under the sod, and if he is watched, he will often be seen to pull the worm from that very spot.

When a woodpecker taps on a tree trunk and turns his head to listen, it is thought that he hears the grub stir under the bark, for when he begins to cut the bark away, he is pretty sure to find and draw it out.

Birds that are much hunted by men, like ducks and geese, get to be very knowing, and show how wonderful is their hearing. They can tell the difference between a noise made by an animal and that made by a man. A deer or any animal may crash through the bushes, and they pay no attention to it, but if a man makes the least sound they are off in an instant.

A bird's ears are behind the eyes, and a little below them. They are covered by delicate feathers that hide them from sight. When the bird raises these feathers—perhaps to hear better—they look like tiny ear muffs.

Owls have little flaps of skin with which they can shut up their ears when they wish to be quiet. This must be very useful to birds who prefer to sleep during the day, when nearly everybody else is awake and making a noise. Many of us who live in cities would like to be able to close our ears sometimes.

Mr. Bolles tells a story about the sharp hearing of a heron. The bird was on a tree dressing his plumage, and he was hidden in some bushes and could not be seen.

Mr. Bolles made all sorts of noises to start up the heron and make him fly. First he imitated animal sounds. He quacked, and barked, and mewed, and brayed, and the bird looked interested, but not at all alarmed. Then he whistled and sang, and at last talked plainly, but the bird only looked over his way, as if to see what new sort of beast was hidden there.

No noise that he could make startled the heron in the least, until a twig snapped under his foot, when the bird was off like a shot. That sound he well knew was made by his most feared enemy, man.