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A LL the insects about which we have been reading are different when they are young from what they are when full grown. But young Crickets and Grasshoppers when they come out of the egg are much the same as when they are older, except that they are smaller and have no wings. They jump and eat and behave in the same way as their parents, and change their coats four or five times. After the last change you can see their wing-cases under the skin, and, when this bursts, they spread their wings and fly.
If you make a cage of wire gauze and put some young crickets in it, and feed them with damp leaves, you may see these changes. But do not try with a muslin cover, as a friend of mine did. For crickets have strong jaws and soon eat their way through.
The little green Grasshoppers of the fields are easy to find, but the large green Grasshopper (see p. 71), is not so common. Still if you know where to look, in the nut-hedges and woods, you may often catch one, and it is a fine insect to examine. His head is well separated from his front body or thorax, and he has two very long feelers which lie back over his body. His jaws are very strong, and if you give him a leaf to eat, under a glass, you can see how they move sideways to cut the food, and the upper and lower lips, through which he passes it to his chewing jaws inside.
If you have caught a female, she will have a curious long tube or egg-layer at the end of her body, which she forces into the ground, to lay her eggs, and this will show you the way that other smaller insects do it.
And now you will want to know how a grasshopper chirps, for you will remember that no insect can make any noise with its mouth. Put your finger gently along, under the left front wing of the great green Grasshopper, close to where it is joined to the body. You will feel that it is rough like a file. The grasshopper rubs this file against the edge of the other wing, and makes the rasping noise.
The small green Grasshopper (2, p. 71), which has short feelers standing forward from his head, makes his chirping noise in another way. He has a file on the inside of his hind leg, which he rubs against the top of his wing. This little grasshopper is really a small locust, like those which fly in swarms over Europe, eating every green thing. which comes in their way. Fortunately for us, though he eats very greedily, our little friend is not so destructive as they are. Locusts have no egg laying tube; they drop their eggs into the loose earth and cover them up.
Crickets are very like grasshoppers, and make their chirping by rubbing their wings together. The females have long egg-laying tubes, as you will see if you can catch a mother cricket in the kitchen. She lays her eggs behind the oven or near the fireplace, where they will hatch all the year round in the warmth.
Grasshoppers and crickets do not chirp to please us, they are calling to each other. Therefore they must be able to hear. Where do you expect to find their ears? I am sure you will never guess.
Look under the wing of the small grasshopper on the first ring of his abdomen, the one behind his hind leg. There a little above his breathing holes, you will see a very small hole. This has a thin skin over it, and it is his ear. The great grasshopper has his ear in a still more curious place, on his front leg below his knee (e, p. 70).
I expect you will know the Field-cricket (3, p. 71), for though it is very timid, and seldom comes out in the day, yet if you find out where it lives, by its chirp, and poke a blade of grass down the cracks of the earth, it is sure to seize it, and you can draw it out. Many country children get them in this way. A Field-cricket is rather larger than the House-cricket; his body is more yellow, and his chirp much more shrill. He is very useful in the garden, for he feeds on insects as well as plants, sitting outside his hole at night to catch them. But by day he is always in the ground, where the young ones remain all the winter till they get their wings.
I wonder if you have ever found a Mole-cricket? There are plenty in England in sandy ground, especially in damp fields, and on the banks of canals and rivers. But they do not live in all parts of the country, and they are very shy. only coming out at night. They make a strange croaking cry, and by it you may know that there are some in your neighborhood. Then you must look along the river-bank, or in a sandy and damp part of the garden, and if you can see ridges of earth thrown up, most likely the Mole-cricket will be working underneath.
He is a very curious insect, about half an inch long with a small head and long feelers, a very broad thorax, and thick flat front legs, ending in large feet like a mole, with sharp black claws. With these he digs his way through the earth, just as the mole does, and his body is covered with soft hairs, brown above, and yellow beneath, to keep off the damp earth. He does great mischief if he gets into a garden, for he tunnels along, eating the roots and stems of the plants. The mother Mole-cricket has no egg-laying tube, for she does not want it underground. She lays about 200 eggs in a chamber at the end of the run, and the young Mole-crickets live there for two or three years before they get their wings. If you can find a nest, and get a few of the young ones, you may see their curious shape.
There are two other straight-winged insects which you know quite well. One is the Earwig, of which some silly people are afraid, though it does no harm to anyone. Its pincers are used to fold its long hind wings under its short wing-cases, and the only mischief it does is to eat our flowers. The mother earwig is very affectionate. She carries away her eggs if they are disturbed, and watches over her little ones till they are full-grown.
The other straight-winged insect is the Cockroach, which people call "black beetle." It is not a beetle, for it does not grow out of a grub, and it is not black but brown. The young are like the old ones, only smaller and without wings. The mother cockroach never has any wings. She carries her eggs in a curious way at the end of her body in a case like a purse, and hides it behind the oven, or under the boards, just before the eggs are hatched. These cases are brown, horny, and shaped something like a bean. Inside there are about sixteen eggs, neatly arranged in two rows like peas in a pod. Cockroaches are very disagreeable and destructive insects. They eat everything they can get, and have a very repulsive smell.
Try to find the different kinds of grasshopper and cricket, both full grown and before they have their wings. Examine the wings of an earwig. Find the egg-cases of the cockroach.