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 débris, in fungi, and in 
similar situations. SSometimes the larvae and pupae are rather numerous 
in stored roots and tubers, especially potatoes, in which cases they may 
assume an economic importance (Johannsen, 1910:34-385; Carpenter, 
1912). The specimens used by the writer for study are part of Johannsen’s 
material, determined as 7’. 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........... Generalier? eres Dufour, 1840: 161. 
Trichocera regelationis........... Larva, general....... Schmitz, 1909:80, pl. 8, fig. 3. 
Trichocera regelationis........... Lanvaspupa seeps Johannsen, 1910:34—35, figs. 51- 
57. 
Trichocera regelationis........... PUpatr ac see cee De Meijere, 1916: 194. 
Trichoceng: Memalisc sacs eos Larva, general....... Curtis, 1846b. 
Trichocera hiemalis.....:........ General See eee Cameron, 1917:63. 
TiC hOCER Osi USCOLO cere ice Generally: ea Carpenter, 1912. (Damage.) 
Trichocera sp....... See pes ess Larva..... Pals wince eager Bremi-Wolf, 1846:175. 
imiGhoceraoxspareces saccre. ee ATS VN eee sy need Sree Perris, 1847:37, pl. 1, fig. 3. 
iniGhOCEnOsS Drees Generslkt ese Bezzi, 1911—12:46-47, 49. 
evChOCENGsSPHe ene eee MAT Vas se cmec eng e nea De Meijere, 1916:191-194, figs. 
21-23. 
WTIANKOUHG Sane o ou dbcacgaossaen Larva, pupa...::...- Keilin, 1912. (Morphology.) 
DrichOCeransprsee sae ee ae ba TVCl aR IA ee cee Malloch, 1915-17 b: 234-235, pl. 
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 XTX, 49). Pseudopods lacking. 
Head complete, non-retractile, strongly chitinized; lateral plates of head widely separate 
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 thi 
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 segmen 
