er wings.
They shut down very tightly. They overlap, as you can see, just below
where they are fastened to the insect's body. Thus they form a very good
roof.
[Illustration]
What wonderful wings the grasshopper has!
And there is something more to be said about them.
Some species of locusts use their wings as musical instruments. When
they wish to, they rub the upper end of the inner wings against the
upper end of the wing covers when they are flying.
This makes the crackling sound we sometimes hear when the locusts fly.
What is that, Mollie? You have caught a locust that has no wings at all?
Who can guess why?
Ah, yes, our wise John says he thinks it is because it is a young one.
What makes you think so, John?
I know, you remembered the larva of the dragon fly and of the May fly.
[Illustration]
Those larvae had no wings at first, but the wings grew, and finally at
the last moult they were full-sized.
When first hatched, the locust larva is like the full-grown locust,
only, of course, it is very small, and it has no wings at all.
It is a little dot of a thing with an enormous head.
Here are three clinging to a blade of grass.
Are they not funny little rascals!
The baby locust eats and grows and moults until, finally, the wings
begin to show as little pads at its sides.
[Illustration]
It is easy to find these half-grown grasshoppers in the middle of the
summer.
Here is one that little Nell has caught.
See its wing pads.
Mollie says they are rudimentary wings.
It continues to eat and grow and moult, and the little wings are moulted
off with the rest of the skin--for the wings of the insect are only
modified parts of the skin.
But there are new and larger wings underneath, and these grow and are
moulted off with the next skin, until, at last, the grasshopper is
full-grown, with full-grown wings.
It will not moult any more after that.
When full-grown, the females lay their eggs.
Where do you suppose they lay their eggs?
Some of them make a hole in the ground.
The end of the abdomen is very strong and sharp, and the locust can make
a hole with it quite easily.
When the hole is made, then the eggs are laid in it, and the locust
covers the opening to the hole with a sticky substance to keep out the
wet.
The eggs usually lie in the ground all winter.
[Illustration]
Just think of the locust eggs there are under our feet as we cross the
fields!
Milli
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