20 Psyche [March-June 
ant and Palmer). Type in the Museum of Comparative 
Zoology. 
Microdon investigator n. sp. 
Plate II, fig. 7 and 8. 
Male. Sides of front nearly parallel, slightly converging 
to vertex, narrowest just across ocelli. Front smooth, shin- 
ing brownish black, punctate. Antennse situated just below 
upper point of middle third of profile. Profile of head evenly 
rounded, remarkably convex. Cheeks very narrow, invisible 
in profile. Face widest just below antennae. Sides nearly 
parallel. No antennal prominence. Antennae light orange, 
first joint twice length of second, third equal to first and 
second concave dorsally, drawing out to a sharp point, sug- 
gesting a thumb. Arista pale, slightly longer than third joint. 
Face shining brassy brown, with a suggestion of violaceous 
color. Pile of face, front, vertex sparse brassy yellow, 
appressed on face. 
Thorax and scutellum dark, moderately shining brown, 
pile golden, thick and markedly appressed. Pleurae similarly 
colored with a conspicuous patch of dense golden pile. Pile 
of scutellum erect. Squamae and halteres light yellow. 
Abdomen pale yellowish brown, third and fourth with 
basal halves and nearly the whole of the fifth segment dark 
brown. Pile of light area exceptionally dense and appressed, 
golden; of dark area black. Venter pale brownish yellow, 
sub-translucent, the lateral edges continuously black. 
Legs light brownish yellow, except for a dark brown spot 
about the middle of antero-ventral surface of each femur 
and the basal third of the tibise, paler yellow. Hind femora 
with anterior diagonal scar or cicatrix on basal half. Hind 
basitarsi nearly as long as remaining segments inclusive; 
twice their thickness. 
Wings palely but uniformly brownish; termination of 
fourth longitudinal vein sharply rectangular, its angle 
emitting a spur; an angle of discal cell rounded. Spurious 
vein quite faint. Spur from third longitudinal vein promi- 
nent. 
Length 13.5 mm. 
One male, Galog River, Mt. Apo, Mindanao, Philippine 
