98 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. 62. 
nae black, first two joints gray pollinose; first joint about as long as 
the third; black bristles of first jomt rather long. 
Thorax gray pollinose, dark on the mesonotum, with two whitish 
vittae, the margins also paler; mesonotum with short reclinate yel- 
lowish pile and erect black pile. Pleura dense whitish gray pollinose, 
thickly white pilose. Scutellum with a dark-gray spot at base, the 
margin paler, the pile reclinate yellowish; four black bristles on the 
margin. Knob of halteres whitish, the base black, and stem brownish. 
Abdomen black, gray pollinose or yellowish gray; pile on the first 
five segments white or yellowish reclinate from the third to the fifth, 
the sixth, seventh,.and the genitalia short erect black pilose. Sec- 
ond segment with the base broadly blackish, narrower on the third, 
fourth, and fifth; segments four to seven with a narrow black poste- 
rior margin, wider in the middle and connected with the base of the 
segment by a faint black line. Genitalia shining black. Femora 
black; knees, tibiae except tips, and base of tarsi yellow, the last tar- 
sal segments and tip of first black. All bristles of the legs black. 
Wings gray hyaline, the costal vein, R—1, and base of wing yellowish, 
the rest of the veins blackish; cell M-3 closed in the margin or nar- 
rowly open. 
Type locality——Hood River, Oregon, June 13, 1917 (F. R. Cole). 
Type.—Female, Cat. No. 25936, U.S.N.M. 
Paratypes.—In addition to the type, two females were examined, 
both specimens in the collection of R. S. Sherman of Vancouver, 
British Columbia; the specimens were collected at Savary Island, 
British Columbia, July 18, 1917, by Mr. Sherman. 
The male is probably very near the male of candidata and vialis. 
The antennae are not the same as in candidata and there is more 
black pile on the frons, darker wing veins and different abdominal 
markings; the femora are black to the tip. 
THEREVA BIMACULATA, new species. 
Female.—Length 8 mm. Very nearly like 7. vialis. Upper two- 
thirds of frons pale brown, with two large velvet black spots which 
almost meet in the middle; the lower third of frons silvery gray and 
with a few short hairs. Antennae black, the first joint quite thick 
and with only a few apical bristles, white pilose, slightly longer than 
the third joint. Face silvery white pollinose with white pile; palpi 
and proboscis with white pile; occiput whitish, with white pile and 
black bristles. 
Thorax and pleura black, covered with gray pollen, the pile short 
and white. In the somewhat poorly preserved type no markings are 
visible; in a perfect specimen there is probably more or less brownish 
pollen on the thorax. Knob of the halteres pale yellowish, the stem 
and base of knob brownish. 
