AQUATIC INSECTS 



Helius. — One "species (Fig. 224) of the genus Helius, form- 

 erly called Rhamphidia, is a common inhabitant of cat-tail 

 marshes where it lives near the surface among floating leaves 

 and refuse. Length of larva, about a half inch. 







Fig. 225, — A carnivorous cranefiy, Limnophila. 



Limnophila. — The lar\^as of Limnophila (Fig. 225), agile and 

 snakelike in their movements, are among the most carnivo- 

 rous of all cranefly larva;. They live in water-soaked muck 

 rather than in open water; some burrow in damp soil. 



Length of larva, about half an inch. 



Fig. 226. — Larva of Pedicia. 



Pedicia. — ^The common eastern species, Pedicia albivitta 

 (Fig. 226), is a dweller in cold springs throughout the north- 

 eastern United States and Canada. 



Length of larva, one inch and a half. 



Giant cranefly, Tipula abdominalis. — This is a ver>' large 

 and very common cranefly. The larva;, often more than tvro 

 inches long, are abundant among the water-saturated, decay- 

 ing leaves of little streams and are frequently turned up with 

 such litter in midwinter collecting (PI. I). They are her- 

 bivorous, feeding chiefly upon diatoms and decayed plant 

 tissue. 



Midges, Family Chironomidae. — On late afternoons in 

 spring, swarms of little flies disport themselves in the sun- 

 shine. They fly low, catching on clothing and gathering in 

 the corners of window panes; in the evening they swarm 

 around the lights. They are midges belonging to the family 

 Chironomidce, minute, delicate flies which are mosquito-like 



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