294 COMMON LOUSE. 



19. GNAT TRIBE. 



Most of the Gnats drop their eggs into the water, 

 where, afterwards, the grubs are hatched, and reside 

 until the period approaches for their change into winged 

 insects. 



Common Gnat. In low and marshy situations, Gnats 

 are very numerous, and extremely troublesome. They 

 make a piping or humming noise with their wings, which 

 is oftentimes irksome where they abound, especially during 

 the night. Their bite is painful, and in some persons is 

 followed by unpleasant swellings and inflammation. 

 The females deposit their eggs on the surface of the 

 water ; and the larvae, or grubs, begin first to appear 

 about the month of May. They are devoured in 

 immense numbers by fish and water-fowl of almost all 

 kinds ; otherwise their increase would be such as to 

 become seriously injurious to mankind. 



The Musquito, so much spoken of by voyagers and 

 travellers in the countries of hot climates, is nothing 

 more than a large variety or kind of Common Gnat. 

 It is the female only that sucks the blood. 



ORDER VII. APTEROUS INSECTS 



20. LOUSE TRIBE. 



All these insects subsist on the juices of animals, 

 which they extract by means of their mouth or sucker. 



Common Louse. This filthy and disgusting creature 

 harbours in the hair and clothes of dirty and diseased 



