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The midge that from a blood-worm grows, The drone fly every gardener knows, The cranefly, and mosquito, too, Are all called Diptera, and you Will see they have a single pair Of wings, and know them anywhere.
MIDGES, drone flies, mosquitoes, and craneflies, as well as houseflies, belong to a group of insects called Diptera, meaning two-winged. In place of the hindwings are two halteres. These are well illustrated in the drawing of the cranefly which appears in this chapter.
Larvae of mosquitoes and of many crane-flies live in the water.
The mosquito larva, or "wriggler," as well as the pupa which appears to have its
head tucked under its thorax, are familiar forms to almost everyone. The larvae have air-tubes at the ends of their bodies
through which they breathe air at the surface. The pupae breathe at the surface, also, through air-tubes in the thorax. This explains why people pour oil on ponds and puddles to get rid of mosquitoes.
The adult females of the common mosquitoes are the ones that bite and suck blood; the males are said to live on the juices of plants and fruits.
One way in which the malaria-carrying mosquito can be distinguished from the common one is by the position of his body when at rest. The common mosquito holds his body parallel to the surface; the malaria-carrier holds his head downward, with the end of his body up in the air.
The adult craneflies, too, are familiar insects. They look like large mosquitoes at first glance, but when examined more closely it will be seen that their wings are scale-less. They fly into houses at night around electric lights. It is possible to discover several different kinds in a few moments during summer evenings. Among these is sure to be the giant cranefly here illustrated.
Craneflies, sometimes called "daddy-longlegs," are often found on berry bushes in
the day time. It is believed that they live on fruit and flower juices. The one shown in the drawing lived for five days in a well-
ventilated "cage" but, unless he ate at night, did not take any food at all except a few drops of water. He spent most of his time sitting motionless in one spot.
Most cranefly larvae breathe by extending the tips of their rather worm-like bodies up to the surface of the water, where special air-tubes take in air. Some live in moist places rather than in the water. A few larvae are carnivorous; others are vegetarians.
An interesting fact about the cranefly larva shown here is that the two dark dots which may have been mistaken for eyes are really respiratory tubes located at the end of the abdomen rather than at the head end.
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