Flies and Mosquitoes, etc.
This is a very big order, there being over 5,200 species in the British Isles.
There are nearly 300 species of crane fly in Britain. The larvae of this species are the leather-jackets, notorious to both farmer and gardener for the damage they do to the roots of grasses. The one most generally seen is the daddy long-legs, which is brownish and, including the unstretched legs, about 1-¾ in. long.
Flesh flies, of which there are about 330 species, include the brilliant bluebottles and greenbottles. Their names are descriptive of their colours, and they range from ¼ to ½ in. They live on all forms of decaying matter, particularly carrion, and are spreaders of disease. Some of them are parasitic in the larval stage.
Hover flies take their name from their habit of hovering motionless in the air, their wings almost invisible. There are about 230 species in Britain, most of them brightly coloured. Many of them resemble bees or wasps. They take nectar from, and in the larval stage many of them live on aphids.
Mosquitoes, of which there are 49 species in Britain, are brownish and require stagnant water to breed in. Their larvae are frequently to be found in the garden water-butt.
Clegs, which are one of the 28 species of the horse fly, do no harm in gardens but, like mosquitoes, attack the gardener. They are blood-suckers and the wounds they make can cause much irritation. They are about ½ in. long and are dark grey or black.