It moves, and pulls, and gets free from the hard case. Then it strikes the end of the case with its head time after time. At last it breaks the case open, and out comes the fly! Then it stands in the air, and in the sun if it can, and shakes itself. It is cold and weak; but the air dries its wings and blows out the wrinkles. In a very few minutes the fly is strong and gay. Then it spreads its wings and sails off to enjoy its life, and to look for something good to eat. LESSON XVII. HOW TO LOOK AT A FLY. Do you think a fly is a very small and common thing? Is it not worth looking at? Let us see about that. First, here is its head with two great eyes. We will soon look at the eyes. Then you will see how curious they are. There are, besides the big eyes, three little eyes. These are set on the top of the head. Then, too, on the front of the head we find a trunk or tube. And here is a pair of feelers. Inside the head is the brain, very much like a worm’s brain. It is only a tiny white dot. Next behind the head is the chest. The head has the shape of half of an egg laid sidewise. The chest is nearly square. It is made of three rings. On the first ring is a pair of legs. On the next ring is a pair of legs and a pair of wings. The fly has only one pair of wings. On the last ring is a pair of legs. And near these legs are two little clubs covered with fine hair. It is by means of these clubs that the fly can halt or balance on the wing. They help the fly as the second pair of wings helps other insects. [Illustration: On the Wing.] The third part of a fly’s body is the largest. It is egg-shaped, and joins the chest by the thick end. This part also is made of rings. Now let us look at the head of a fly. The feelers are like two long, fine plumes made in joints. Most people think these feelers are made to touch with. Their full, true use is not yet known. You see, even in a fly there is much left for some of you to find out. Some people think that flies smell and hear with these “feelers.” But then they are so fine that a breath can jar them, and the fly might _seem_ to hear when it only feels. I know of something else like that. It is this. In some schools for the deaf and dumb, the pupils are called to class or table by rapping on the floor. The deaf do not hear the noise, but they feel the jar, and come as if they could hear. Let us look at the mouth of the fly. The lip of a fly runs out into a long, slim tube or pipe. With this it sucks up its food. At the end of this tube is a little flat plate. Close by it are two sharp hairs. These are to prick the food, so that the tube can suck it more easily. When the fly is not eating, it can shut up this tube like a telescope, to keep it safe. Did you ever see an elephant? Did you see his trunk? The fly’s tube is his trunk. The elephant’s trunk is his long upper lip. So is the fly’s trunk a long lip.