FIELD BOOK OF PONDS AND STREAMS 



usual flight attitude with broadly outspread legs, the swollen 

 metatarsi hanging vertically, all phantom-like in slenderness 

 and in strongly contrasting black and white. It came from 

 below the level of the rail, swept past within two feet of my 

 face, and passed on upward with the breeze until lost to view, 

 perhaps lOO feet higher than the bridge, and much farther 

 upstream. Since the creature can fly only very slowly and 

 here was moving several times faster (I could not see whether 

 it was using its wingsj, it was obviously drifting in the wind. 

 Perhaps this is a normal function of the expanded metatarsi." 



The rusty red larvae live in shallow water filled with de- 

 cayed vegetation, among which they lie with the breathing 

 tube pushed up through the surface film (Fig. 222). Like 

 the larva, the pupa rests beneath the water with its air-tube 

 at the surface. The larva becomes an inch and a quarter long. 



Common and widely distributed in eastern North America. 



Typical cranefiies, Family Tipulidae.— This is by far the 

 largest family of cranefiies, containing nearly 3000 species 

 found in most parts of the world. 



Fig. 223. — A swift-water cranefiy, larva of 

 Antocha. 



Antocha. — The lar\^a of Antocha (Fig. 223) is found upon 

 stones in rushing torrents. There it lives in a crevice or 

 among pebbles within a silken case one to two inches long and 

 open at both ends, breathing through its four tracheal gills 

 and the tracheae of its caudal lobes. The pupa lives in the 

 case previously used by the larva, its head always pointing 

 downstream. Distributed over the northern hemisphere. 



Fig. 224. — Larva of Helius {RJiaynphidia) . 



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