NATURAL HISTORY OF THE FARM 



FIG. 117. The buffalo-gnat .(Simulium 

 pecuarum, after Gannan). 



and filled with water by 

 the rains, often furnish 

 the chief supplies of mos- 

 quitos to a whole neighbor- 

 hood. Few are reared in 

 open water inhabited by 

 fishes; for the fishes eat 

 them. The smaller the pool, 

 the more likely it is to 

 contain mosquito larvae. 

 The larvae take air at the 

 surface of the water, but 

 swim down below to find 

 forage or to escape danger. 

 Many species are adapted 

 to the drying up of their 



native pools, and live on (usually in the egg stage) in 



absence of water, and come on again and fly and sing and 



bite at their proper seasons. Some are short-lived, and run 



through quite a number of generations in a single summer; 



these develop in vast numbers when a rainy season main- 

 tains an abundance of little pools. 



Black-flies (Family Simuliidae) develop in running water, 



and are most troublesome about woodland streams. The 



habits of the larvae, which live 



upon stones, have been discussed 



on pages 36 and 37. When there 



are no stones in the streams, larvae 



may be found hanging to sticks 



and to grass blades that trail in 



the edge of the current. The eggs 



are laid on logs and stones at the 



water's edge. The adults (fig. 117) 



love the sunshine, and their biting 



is troublesome only by day. u. s. 



