art. 4, REVISION OF THE FAMILY THEREVIDAE—COLE. 59 
Thorax thickly dark gray pollinose, with two vittae and lateral 
margins light gray, the pile mixed black and white, the bristles black. 
Scutellum colored as thorax, with white pile and four marginal 
incurving black bristles. Pleura gray pollinose and white pilose, 
especially dense pile on the propleura. Stem of halteres yellowish, 
the knob largely yellowish but with a blackish base. 
Abdomen black, first segment gray pollinose, second largely black, 
semishining, the posterior margin and sides gray pollinose, a narrow 
margin white; base of third, fourth, and fifth, and all of seventh seg- 
ment shining black, the rest gray pollinose. First three segments 
with white pile, the last four with erect black pile as on the venter, 
which is wholly gray pollinose; genitalia black. Femora black, gray 
pollinose and white pilose; knees, basal two-thirds of front tibiae, 
three-fourths of hind tibiae, and bases of tarsi are yellowish brown. 
Wings hyaline, stigma pale brown; fourth posterior cell broadly open ; 
wing veins dark brown. 
Male.—Length 10 mm. Very nearly resembling the female. The 
eyes are contiguous for only a short distance, the frontal triangle 
large, silvery pollinose and with no sign of pile. 
Vittae on mesonotum more definite than in the female and all the 
pile of thorax a little longer and more dense. In the two males 
examined there is a small, round, black spot at the base of the 
abdominal segments; the spot is near the middle and next the basal 
black border. Genitalia largely blackish and gray pollinose. All the 
pile of abdomen long and white, longer at the base; several black 
hairs beneath on the genitalia, the rest of the pile on the genitalia 
yellowish. (Fig.101 for structure.) Legs almost entirely blackish in 
the typical specimen. 
Pupa.—Length 12.5mm. The color is yellowish; the thorns on the 
head and thorax rather short. Thorax not as highly arched as in 
P. argentifrons; beneath each spiracle along the sides of the abdomen 
there are two spines. First abdominal segment with six bristles 
above; there is a tendency to variation in the other rows of spines on 
the abdomen; on the last two segments there are 8 spines above and 
on the others from 10 to 12. On the venter of segments 2 to 7 there 
are 6 spines, 3 on each side, or at times 3 on one side and 4 on the 
other. The body ends in the usual bifid spine. (Fig. 173.) 
Type localities—Colorado and Washington. 
Cotypes.—Females, No. 10419, U.S.N.M. 
The neallotype male is in the collection of R. S. Sherman and 
was collected in the Hope Mountains, British Columbia, July 21, 1919 
(Sherman). 
The female listed below from Bear Valley, California, was bred 
from a pupa taken from an old pine log. The female from Colorado 
