vacationers, and hikers are also pestered by them. The health of domestic animals 
and wildlife suffers with serious losses of weight and disease. 
Twelve genera and 148 species of true mosquitoes occur in the United States and 
Canada (//73). The larvae and pupae live in standing or slowly moving bodies of 
water that range in size from small accumulations held by plants to vast salt 
marshes. Many of these are included in a review of mosquitoes in the Southeast 
(666). 
Family Ceratopogonidae 
Biting Midges 
This family contains a number of species of very tiny flies, usually | to 4 mm in 
length, that feed on the blood of humans and other animals. They are often 
abundant in the vicinity of fresh water inlets along the seashore or near fresh water 
streams, ponds, and pools. Woods workers, hikers, hunters, fishers, picnickers, 
and others frequenting these areas often find their presence almost intolerable 
because of their very burning and painful bites. Populations are heaviest during late 
summer. At this time, these flies bite chiefly in the evening and very early in the 
morning. Some 27 genera and 348 species occur in America north of Mexico 
(1341). 
Family Chironomidae 
Midges 
Midges are small, slender flies, rarely over 10 mm in length (//77). They 
resemble mosquitoes, but do not have fringes of scalelike hairs on the wings. They 
differ also by the discontinuation of the costal vein at the end of the third vein. 
Midges are frequently seen in great swarms, dancing in the air, usually in the 
evening. The larvae of most species are found in the water of streams, usually 
attached to the surface of stones, sticks, and other objects. Many are red and are 
commonly known as bloodworms. Midge larvae are fed upon by many freshwater 
fishes and other aquatic animals. 
Family Simuliidae 
Black Flies 
Black flies occur in nearly all parts of the United States and Canada (//74). In 
different parts of their range they have various common names such as buffalo gnats 
and turkey gnats, as well as black flies. The females feed on the blood of humans 
and other animals and their bites cause swelling, itching, and sometimes bleeding. 
Their habit of hovering about the face and getting into the eyes, ears, and nostrils 
makes them a nuisance. When they appear in large numbers, birds and animals may 
be literally smothered by flies drawn into their air passages. In the woods and 
mountains of the Northern United States and Canada, they are often so abundant in 
the spring that they are almost unbearable. Black flies have also been incriminated 
in the transmission of several diseases of wild and domestic birds. 
Black flies usually lay their eggs on grass and other materials just below the 
surface of water in swiftly flowing streams. The larval stage is spent in the water, 
usually attached to sticks, stones, or living vegetation. Adults are not strong fliers 
and usually are encountered in large numbers not too far from streams. Sometimes, 
however, the wind blows them a considerable distance. 
Family Bibionidae 
March Flies 
March flies are slender-bodied, stout-legged, rather hairy, and have short, many- 
jointed antennae. They are usually dark, but may be marked with red or yellow. 
Full-grown larvae are distinguished by a fully developed false segment, armed with 
spines behind the head. The common name, March flies, has been applied to the 
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