I TOLD you the earth-worm has two veins. One runs down his back, the other runs along the under side of his body.
There are tiny holes, like pin pricks, in his body. These are for the air to reach his blood, to keep it red and pure.
In his body poor Mr. Worm has something that no other creature has. He has two bags or sacks for lime. This is in some way to help him with his food.
Mr. Worm has no teeth with which to grind his food. He has inside his body small bits of stone. These are as small as grains of sand. They are instead of teeth to grind his food.
When you study birds you will find that, like Mr. Worm, they have no teeth. They, too, carry little millstones inside their bodies.
The little bags of lime help to grind or change the worm's food in some way, not yet well known.
The soft body of the worm will stretch like India-rubber. It will hold a great deal of food.
Now you see that Mr. Worm is not alike at both ends. One end has the head, the stomach, the parts that serve for a brain, and a heart.
The hooks begin at the fourth ring behind the head. Look at the worm when he lifts his head, and you will see his mouth.
The tail end has very strong hooks with which to hold fast to his cell. This tail end is also his trowel, or mould, a tool with which this poor, ugly worm helps to build the world.
Ah! now I have told you a great thing, a strange thing. Is it true that the feeble, useless worm helps to build the world? Where is that boy who knew so much about worms?
But before you hear how the worm helps to build the world, let us go back to what the boy said. He said, "If you cut the worm in two, each end will go off and be a whole worm."
That is not true of the worm. When the worm is cut in two, the parts do not die at once. As there are hooks and rings on each part, they each can move off.
It is thought that if the fore part is left safe, the cut can close up, and the worm can still live. A new tail may grow upon the front part, as Mr. Crab's new claw or eye-peg grows.
The hind part cannot live and grow. It cannot get a new mouth or heart, so it can take no food, and have no blood. It soon dries up and dies.
The boy told me that the worm "had no feelings." A worm can feel. The sense of touch is the best sense it has. Put your finger on its body, and see it move and shrink.
If the worm can hear, the organs that serve for ears have not yet been found. It crawls up as you come near, and pokes its head out of its hole and wags it to and fro. It has felt the jar of your steps.
The worm cannot see. Creatures that live under ground have but little use for eyes. Fishes that live in dark cave-rivers have no eyes. If the worm moves from the light and hides from it, it is because it feels the action of light on its skin. It does not see the light.
What does Mr. Worm eat? Some tell you that he eats dirt. It is true that he fills his body full of earth. That is to carry it to the top of the ground. Mr. Crab has claws and legs to bend into the shape of a basket. Poor Mr. Worm has no arms, legs, or claws, so he must make a basket of himself.
Suppose you should be sent for fruit, and turn yourself into a basket in that way! Your mamma might find fault. She would not wish you to act like a worm.
It is true that the worm may find a little food in the earth which he swallows. But the chief food of the worm is dead leaves and stems of plants. It does not care for fresh, live leaves and stems and roots. The worm also likes meat,—fat, raw, or cooked. Worms will gnaw or suck the bodies of dead worms. We say worms gnaw. As they have no teeth, they do not really gnaw. They pinch off what they eat.
Worms like onions and cabbage best of all food. They need plenty of water, and must live in damp places. They soon die if they are put into water. They choke as a fish chokes if kept out in the air.
When the worm gets food into its mouth, the rings of its body begin to move out and in. They look as if they were opening and shutting. By this motion they press the food down into the body.
When the worm wants to move, it stretches out its body to its full length. Then it takes hold of the earth with its hooks. Next it draws up its body, and so moves on. This is a wave-like motion, you see. Watch it, and you will see that it travels with a motion like waves.
If you wish to find worms to study, you must seek for them in early morning or late in the evening. You will be likely to find them when all the earth is moist with dew, or when it is raining. They avoid heat and sun.
Worms hurry to the surface of the soil to enjoy the falling rain. When there is a long, dry time, the worms go down deeper and deeper into the earth. You cannot find them when you dig for them. They need to keep down where the earth is moist, soft, and cool.