The rest of the insects are, in general, much like the ants. They have their feelers or antennae, growing out in front of the head, with which they both feel and smell. Most of them seem to taste their food in their mouths. Nearly all have eyes.

As for ears, a good many insects, apparently, hear as the ants do, without any regular ears, and just by feeling the shake of what they happen to stand on. At least, nothing is known about their having any regular ears; though it is quite possible that some of them hear through their wings. Certainly, a tight hard wing, like a house fly’s, when one wasn’t using it for flying, ought to make a very decent sort of ear, one would think.

Grasshoppers and the like have proper ears. Though instead of being where we have ours, on the sides of our heads, Grasshopper Gray carries his ears on his hind legs, on the side of his great jumping thighs; while the ear itself, instead of looking like a human ear, is like a tiny drum—a tight thin head with a hollow underneath. Some other insects have their ears on the side of their bodies, about the middle. You can see these things for yourselves; they are not hard to find.

Some of the jelly-fishes have ears, not at all good ones, but still ears. Some also have eyes, not so good even as the ears, and not good for much anyway. But the same kind of jelly-fish doesn’t have both ears and eyes; whichever he gets, he goes without the other, having apparently not sense enough to manage both. As for the sea-cucumbers, they sometimes have more than fifty ears apiece, none of them good for much.

Most all of these simpler sorts of ear are much like tiny rattles. There is a hollow ball lined with nerves. Inside the ball is a small hard ear-stone, or a number of smaller grains of ear-sand. When a sound comes along, (for a sound is nothing but jar), it shakes the rattle, so that the little stone inside bangs against the nerves. Then the animal hears. In the cod fish these ear-stones are unusually large, as large as the end of one’s thumb; children sometimes call them lucky-bones, and use them for playings. We also have these little rattles, two in each ear, with ear-sand. But these, which are all there is to the ears of lowly creatures, are only a small part of our hearing machinery.

You will find the ears of lobsters and crayfish, which are little fresh water lobsters, just at the point where the smaller feelers, which are double at the end, join the body. These, too, are merely ordinary ear-rattles; you can make out the opening on the upper side of the feeler. Of course, you know the ears of the frog—the big spots on the side of the head, back of the eyes. These spots are the drums of the ears; the real ear, much like our own, is inside. We have such a drum, only it is at the inner end of the hole into the ear, where it is much safer than it would be outside.

The fish’s ear you cannot find. That is inside; and the fish hears through the bones of his head, just as we do when we hold a stick in our teeth and tap the end, while we keep our ears stopped with our fingers. But the long dark stripe which you see on many sorts of fish, running from the place where the neck would be if fishes had one, the whole length of the body to the tail, and also forward across the head and around the eye, only you can’t make it out so well there, this also is a sort of ear. In fact, the ear itself is really a part of this “lateral line” very much improved—so much improved that we human beings and the four-footed beasts and the birds haven’t found it worth while to keep the lateral line at all. But the newts and salamanders still have it.As for eyes, of these also there are all sorts. The star-fish has five, one at the end of each of its five arms, a tiny black dot. The jelly-fishes, some of the commoner sorts at least, have their eyes, such as they are, where the long tentacles join the center of the bell underneath. Some of the worms have several hundred eyes; some have a pair of eyes on each of the dozen or twenty joints of the body. The leeches, the common blood-suckers which get on our legs when we go swimming, have ten pairs of eyes, all on the front end.

Oysters, clams, and other “bivalves” have their eyes along the edge of the shell. Many of the snails have them on stalks, which they can pull back into the head or push out. The snail in Mother Goose, that

and frightened the four-and-twenty tailors, was really only putting out her eyes to see these valiant heroes. Some of the shell-less snails, or slugs, besides the eyes on the ends of their horns, have a lot more, occasionally nearly a hundred, sprinkled over the back.

Such eyes, however, are really not good for much. They serve to tell light from darkness. They let the creature know when a shadow falls on him—which is usually the shadow of something on the point of eating him up, so he gets warning and bolts. We ourselves can do as much with our eyes shut tight; and that’s about all most eyes will do wide open. There are not many really good eyes, till you get the single pair of the animals with back bones.

Still there is one very fair sort of eye, though not nearly so good as ours, and that is the strange compound eye of the insects.

In general, the insects have either one, two, or three little eyes, at the front of their heads, which they use, probably, for seeing things close to them. Besides these, they have their two great compound eyes, often many times larger than all the rest of the head. The two together usually make almost a ball, and with them the bee or wasp or moth or dragon-fly sees clear round the horizon, above him and below him, all at once, and all equally well.

You know if you take a roll of paper, and look through it as if it were a telescope, you see a small bright spot at the end. If you had two such rolls, and could look through them both at once, you would see two such spots. If you had a thousand or more such paper tubes, and could look through all these at once, you would have something very like the compound eye of an insect.

Our eyes, as you know, are cameras. They form real pictures at the back, on the retina. But these compound eyes are not cameras, and they do not form any pictures anywhere. Instead, the insect looks out through one eye tube, and sees one spot of color; and through another, and sees another spot; and through a third, and sees another. Looking through some hundreds all at once, he sees a corresponding number of hundreds of spots.

But even ten thousand such spots would make no such sharp picture as we see in the small center of our field of vision where we see most clearly. Flies and ants and bugs and grasshoppers see only as we see things far round at the sides of our heads. They can see much farther round than we can; but they can’t see nearly so well anywhere.

So a fly never could see to read, even if he could ever learn. The page of letters and the white paper would simply mix to a gray blur. A fly cannot get through a netting with a half inch mesh, unless there is a light behind it. Altho the holes are many times larger than his body, he cannot tell hole from string well enough to fly through. If you try to put your whole hand on a fly, or hit him with one finger, you cannot do it. He sees something dark coming, and stands from under. But you can often get him by bringing down the whole hand slowly; and then, just as he is about to take flight, dropping one finger on his back. He can see the whole hand against the wall of the room; but he cannot see clearly one finger against the others.

So on the whole, the fly does not really see much with his little eye; in fact, taking, one thing with another, we boys and girls and men and women probably see more distinctly, and make more use of our eyesight, than any other creature that breathes.