474 OTHER BLOOD-SUCKING FLIES 



resemble mosquitoes except for the absence of the long proboscis, 

 and the dancing flocks of these insects which can be seen over 

 pools or swamps on any summer day are usually taken for mos- 

 quitoes without question. As expressed by Riley and Johann- 

 sen, " these midges, especially in spring or autumn, are often seen 

 in immense swarms arising like smoke over swamps, and pro- 

 ducing a humming noise which can be heard for a considerable 

 distance." In such swamps the larvae, most of which are aquatic 

 and live in the mud or amid aquatic vegetation, may be scooped 

 up, literally by the shovelful. Fortunately the great majority 

 of these insects are quite harmless, in fact, inasmuch as the 

 larvae are an important food for young fishes, they are distinctly 

 beneficial. The blood-sucking species belong to the subfamily 



FIG. 216. Life history of blood-sucking midge, Culicoides; A, adult male (C. 

 reticulatus), X 5; B, eggs (C. marium), X 18; C, larva (C. reticulatus) , X 5; Z>, 

 pupa (C. marium), X 10. (After Lutz.) 



Ceratopogoninse and are very small; only the females are known 

 to suck blood. They are well known to hunters and anglers and 

 other frequenters of the woods in most parts of the world. In 

 America they are usually called " gnats " or " punkies " and in 

 the West are known as " no-see-ums," on account of their very 

 small size. 



These insects (Fig. 216) can usually be distinguished from 

 allied insects by the peculiar venation of the wings, the first two 

 veins being very heavy while the others are indistinct. Though 

 the bodies, and sometimes to a slight degree the wings, are more 

 or less hairy the scales so characteristic of mosquitoes are ab- 

 sent. The proboscis is never long even in the blood-suckers, 

 and one is led to marvel at the irritation which can be inflicted 

 by such a small insect with such a small organ. Usually midges 



