THE CRANE-FLIES OF NEW YORK PART II 785 



the creature can fly only very slowly and here was moving several times faster (I could not 

 see whether it was using its wings), it was obviously drifting in the wind. Perhaps this is a 

 normal function of the expanded metatarsi. 



The larvae are usually abundant in decaying vegetable matter in rich 

 organic mud about ponds and in swamps. The writer has found them 

 especially numerous in the Basin Swamp at Orono, Maine (in 1913), 

 and near Round Pond at McLean, New York. At Orono they were 

 associated with larvae and pupae of Ptychoptera rufocinda, Limnophila 

 macrocera, Pilaria tenuipes, P. recondita, Erioptera chlorophylla, a variety 

 of chironomid larvae, numerous larvae of Trichoptera in their cases, 

 nematodes, and leeches. Needham and Betten (1901:574-575) give a 

 summary of the larval habitat of this species as they found it in the 

 northern Adirondacks. Weston and Turner (1917:53) have recorded 

 the larvae as being scavengers and thus serving as important factors 

 in the elimination of sewage in the Coweeset Stream near Brockton, 

 Massachusetts. 



The immature stages of this interesting crane-fly have been well con- 

 sidered by Hart (1898 [1895]: 189-195), whose account has been briefly 

 summarized by Howard (1912:95-96). The larvae are found in shallow 

 water that is filled with decaying vegetable matter. Here they live in 

 the mat of dead stems of rushes, grasses, and willow leaves, in semi- 

 stagnant or slowly flowing water. The larvae are elongate-cylindrical, 

 with a long, partly retractile breathing tube. They are deep rusty red 

 or brown in color, quite distinct from the pale whitish larvae of Ptychoptera 

 or the black larvae of Bittacomorphella. They feed on decaying vegetable 

 matter, diatoms, and mud that is filled with organic matter. They rest 

 beneath the surface of the water, with the tip of the extended breathing 

 tube at the surface film or just beneath the surface, in the latter case 

 breathing by means of the small tracheal gills. When about to pupate, 

 the very long, coiled breathing tube of the pupa is wound around the 

 thorax beneath the larval skin. On pupation the tube soon straightens 

 out into a very long, stiff, bristle-like structure. Like the larvae, the 

 pupae rest beneath the surface of the water, with the tip of the breathing 

 tube projecting above the surface film. The pupal duration is apparently 

 about a week. 



Larva. Length when fully extended, about 60 mm. 

 Length of breathing tube, about 20 mm. 

 Diameter of body, about 2.6 to 3 mm. 



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