790 Charles Paul Alexander 



toward the wind or breeze. Mating takes place in the air, and united 

 pairs then fly away or drop to the ground beneath. The swarms are 

 often very dense, and individuals come in frequent contact with one 

 another. When the breeze shifts, the swarm immediately readjusts its 

 position and direction. 



The immature stages of Trichocera are spent in decaying vegetable 

 matter, beneath dead or decaying leaves, in debris, in fungi, and in 

 similar situations. Sometimes the larvae and pupae are rather numerous 

 in stored roots and tubers, especially potatoes, in which cases they may 

 assume an economic importance (Johannsen, 1910:34-35; Carpenter, 

 1912). The specimens used by the writer for study are part of Johannsen's 

 material, determined as T. regelationis from Patten, Maine. The tax- 

 onomic condition of the group is such that no specific identification of 

 the adult flies can be attempted at this time. The immature stages of the 

 generalized subgenus of Trichocera, Diazosma Bergroth, are unknown. 



The most important literature on the genus Trichocera is as follows: 



Trichocera regelationis General Dufour, 1840: 161. 



Trichocera regelationis Larva, general Schniitz, 1909:80, pi. 8, fig. 3. 



Trichocera rcgelalionis Larva, pupa Johannsen, 1910:34-35, figs. 51- 



57. 



Trichocera regelationis Pupa De Meijere, 191G: 194. 



Trichocera hiemalis Larva, general Curtis, 1846b. 



Trichocera hiemalis General Cameron, 1917:63. 



Trichocera fuscata General Carpenter, 1912. (Damage.) 



Trichocera sp Larva Bremi-Wolf, 1846: 175. 



Trichocera sp Larva Perris, 1847: 37, pi. 1, fig. 3. 



Trichocera sp General Bezzi,1911-12:4()-47, 49. 



Trichocera sp Larva De Meijere, 1916: 191-194, figs. 



21-23. 



Trichocera sp Larva, pupa Keilin, 1912. (Morphology.) 



Trichocera sp Larva Malloch, 19 15-17 b: 234-235, pi. 



26, fig. 1; 306. 



Trichocera regelationis, supposition. 



Larva. — Length, 8-9.5 mm. 

 Diameter, 1 mm. 



Coloration pale brown in preserved material, whitish in fresh specimens. 



Body rather short, cylindrical to slightly depressed (Plate XIX, 49). Pseudopods lacking. 

 Head complete, non-retractile, strongly chitinized; lateral plates of head widely separated 

 on midventral line, connected only by a narrow bridge posteriorly; chaetotaxy as shown 

 (Plate XIX, 52 and 53). Mandibles opposed, of three parts, principal segments bearing 

 on inner side near base an apparently movable appendage (prostheca) which has, besides the 

 large apical tooth, three smaller teeth. Labrum bluntly rounded, with long hairs. Epi- 

 pharynx with lateral combs of about six blunt teeth. Antenna two-segmented; basal segment 



