H AVE you heard people speak of swarms of flies? By a swarm of flies we mean a great number of flies rather near together. By a swarm of bees we mean a number of bees that live and work in one place. A swarm of bees divides the work of its hive. It has one queen bee. She is the mother and ruler of the rest.
But flies have no home where they live in common. They have no work. They have no one mother or queen, for whom the rest work. Each mother fly drops her eggs where it seems best to her. Then she goes off. She leaves her children to grow as best they can.
I have said that the fly likes best to place her eggs on a piece of fresh meat.
These eggs soon turn to worms or grubs, and so spoil the meat. To keep the meat from the flies the cook puts a cover over it. The cover is often made of wire net.
"Now," says the cook, "I can keep away that dirty fly."
But Mrs. Fly says, "Oh, can you, Mrs. Cook? We will see about that."
So Mrs. Fly sits on top of the wire cover. She puts her little egg tube through one of the fine holes in the net. She drops egg after egg from the tube. The eggs fall right on the meat, just where Mrs. Fly wishes them to be.
Then the cook cries out, "How ever did that fly get to my meat?"
Is it not strange that Mrs. Fly knows that her egg tube is the right size to go through the mesh of the wire net? How does she know that the eggs will fall on the meat?
Flies do another queer thing. If many flies are in a room, and you begin to chase them to kill them, they hide. They creep into holes and cracks.
They hide in curtains. They go behind pictures. After the hunt is over, out they come, one by one!
Flies also know how to sham death, "play dead," you would say. If you hit one and make it fall, it will lie very still, and seem to be dead. Then, after a little, it softly spreads out its legs and its wings. Then it shakes itself. A moment more, off it goes.
This fashion of making believe to be dead does not belong to flies only. Nearly all insects, and many other animals, sham death. It is worth while to watch and see how well they do it.
When a fly is killed other flies come to eat up its body. They put their trunks or mouth tubes on the dead fly and begin to suck. Soon the body is sucked dry of all its juice. It is only a dry shell.
I will tell you something that you can do with a dead fly. If it has not been dead so long that it has grown too stiff you can make the wings move. Hold it by the body. Gently tip up one wing. As you lift up one wing the other will rise too. They move together. It is as if they were set on a little spring.
It is as wrong to be cruel to flies as to larger creatures. If they are to be killed, do it quickly, and give as little pain as possible. If we do cruel acts, we make our hearts hard and bad.