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FLIES. You may perhaps have seen a common house-fly hundreds of times without caring to notice it much; but if you were to look at it through a magnifying glass, you would find out that it is a very beautiful little creature.
Its body is covered with fine soft grey down, with blackish stripes down the back; its eyes are red, with a white line all round them. They shine like diamonds, and are so formed that the fly can see above and beneath, and all around.
Its wings are like gauze, and it has two tiny tubes or horns upon its head.
These little horns are called the antennce, from a word — ante — which means before; some insects have very long ones, but those of the fly are very short indeed. The fly has also a very useful little trunk, or sucker, through which it sucks up its food.
A gentleman was one day watching å fly feeding upon some lump sugar, and he could not understand how it could get off the morsels of dry hard sugar, and suck them up through its little trunk.
So he looked at it through a magnifying glass, and then saw it let fall a drop of moisture on the sugar; a very little bit of the sugar was thus melted, and now the fly could suck it up; then it let fall another drop and melted a little bit more, and so on, until it had eaten enough.
When we put a piece of hard crust into our mouths, it has to be softened by the moisture which is in our mouths before we can eat it. The fly softens the sugar first, and then draws it up into his little trunk.
The fly's feet are the most curious things which belong to him. Have you ever thought how it is that he can walk up the straight smooth window-pane so easily without ever slipping back again, or how he contrives to march across the ceiling with his back downwards ?
If you have ever played at lifting a stone by means of a piece of leather put upon the top of it, you can understand a little how it is that the fly walks.
Children sometimes get a piece of leather such as the soles of shoes are made of, and when they have fastened a string to the middle of it, they wet the leather and press it closely down on the top of the stone, so closely that no air remains between it and the stone.
The pressure of the outside air upon the upper surface of the leather makes it stick fast to the stone, and when the leather is drawn up by the string the stone is raised with it.
Now the six little feet of the fly take hold of the ceiling, or of the pane of glass, in the same way that the leather takes hold of the stone.
Flies are so troublesome to us in making dirty marks upon our walls and our furniture, that we are apt to think of them as dirty creatures, but there is no creature more strictly clean in itself.
Those little feet, which climb and walk so cleverly, are very useful also as brushes; the fly brushes its legs one upon another to rub off all the dust which is upon them, and then cleans its wings with the hind legs, and brushes its head and clears its eyes with the fore legs.
I dare say you have often seen a fly passing its legs over its head and body : it was then cleaning and trimming itself, so as to brush off every bit of dust.
Yet it chooses very dirty places in which to lay its eggs-dunghills and places where refuse is thrown; for it is upon such things that the maggots which are hatched from the eggs feed.
When they have fed themselves to the full, their skin hardens, and becomes like a little brown case, and in that state they lie for many days or weeks.
In the meantime the little sbapeless maggot is changing into a fly, and at last the case opens at one end, and out creeps the fly, with its wings all crumpled up on each side of its body. These soon spread themselves out however, and then it begins to fly about in the sunshine, and to enjoy its short
WHAT PARTS OF PLANTS ARE
USED FOR FOOD. THE fruits and plants of the earth were given by God for the use of man and beast. A great many of these are fit for the food of man; but it is curious to observe what different parts of different plants we eat.