THE CANADIAN ENTOMOLOGIST 245 
Allied to T. whitneyi; general colour of the head and thorax 
light gray; a narrow, brown or black dorso-median vitta extends 
the length of the thorax and abdomen; antenna? black; femora 
strongly incrassated ; wings indistinctly marked with pale brownish 
clouds; abdomen reddish yellow with a brown dorso-median black 
stripe. 
Male. — Length 10.2 mm.; wing 11.7 mm. 
Palpi dark brown. Frontal prolongation of the head moder- 
ately elongated, deep chestnut-brown, above sparsely dusted with 
gray; nasus lacking. Antenna? dark brown, the scapal segments a 
little more reddish and sparsely dusted with gray; flagellar seg- 
ments rather short, deeply incised, the basal swelling shorter than 
the pedicel of each segment. Head gray, the vertical tubercle 
large, prominent, with an indistinct, brown median line that 
becomes indistinct behind; eyes very small, widely separated. 
Thorax light gray, the usual praescutal stripes not very dis- 
tinct, the median one tinged with brown; scutellum more reddish 
with an indistinct, median brown line; postnotum gray with a 
brown, median line. Pleura light gray, the dorso-pleural mem- 
brane obscure yellowish. Halteres light brown, the knobs a 
little darker brown. Legs with the coxae long and powerful, light 
gray; trochanters chestnut-brown; femora short and stout, con- 
siderably incrassated apically, reddish brown; dark brown at the 
tips; tibia? dull brownish yellow, the tips darkened; tarsi dark 
brown, the metatarsi paler. Wings slightly crumpled, possibly 
the first indications of degeneracy; membrane indistinctly blotched 
with brownish; cells C and Sc a little more yellowish; stigma in- 
distinct, brown; clouds of brown at the origin of Rs; along the 
cord in cell M; apex of cell 1st A, etc. Venation: vein Ri per- 
sistent but pale at its tip; cell 1st M2 very small and short, only a 
little longer than broad; fork of cell Mi deep; cross-vein m-cn 
obliterated by the fusion of Cui on M 3+4. 
First abdominal tergite brownish basally, the remainder of 
the dorsum of segments 1 to 8 light reddish yellow, the 
segments broadly ringed with yellowish; a very conspicuous 
black median vitta runs the length of the abdomen, inter- 
rupted only by the yellow caudal margins to the segments; this 
vitta begins on segment 1 and continues to the eighth tergite; 
