102 PROCEEDINGS OF THE NATIONAL MUSEUM. VoL. 62. 
reddish yellow and quite long. The legs as in the male, in one speci- 
men with some blackish color on the femora. Wings with cell M-3 
widely open. 
Type.—In Krober’s collection. 
Distribution.—Three males and three females were examined, from 
the following localities: 
Massachusetts: Sharon, August 25 [B. S. N. H.]. 
Connecticut: Waterbury, September 26, “on foliage” (C. H. T. 
Townsend), [U.S.N.M.]. 
Rhode Island: Kingston, July 20 [C. W. Johnson]. 
New Jersey: Delaware Water Gap, July 15 [C. W. Johnson]; 
Ridgewood, August 8 (M. D. Leonard), [R. C. Shannon]. 
Pennsylvania: Allegheny County, Jeanette [both Carnegie Mus.] 
THEREVA ALBIFRONS Say. 
1829. Thereva albifrons Say, Journ. Nat. Sci. Phila., vol. 6, p. 156. 
Coquillett considered albiceps Loew the same as albifrons, and some 
other dipterists have come to this conclusion, with which I can not 
agree. CC. W. Johnson has loaned a specimen of what is taken 
to be albifrons Say. The specimen is described below: 
Male.—Length 9.5 mm. Black, largely gray pollinose and white 
pilose. Antennae rather short and thick; the first joint a little wider 
than the third and scarcely as long, the style short and blunt; sec- 
ond joint considerably narrower than either the first or third. Bris- 
tles of the antennae black, the pile white. Upper corner of frontal 
triangle and a narrow line between the eyes dull black, the rest of 
the frons white pollinose and pilose. Face, cheeks, and occiput white 
pollinose and pilose. Post-ocular bristles black. Palpi and probos- 
cis black, with white pile. 
Thorax black, gray pollinose and thinly white pilose. The meso- 
notum is slightly greased in the specimen described, but there are 
evidently two narrow, widely separated white vittae and a darker 
median stripe. Scutellum black, gray pollinose and white pilose; 
there are evidences of only two marginal bristles. All the thoracic 
bristles black. Pleura gray pollinose and white pilose. Halteres 
largely yellowish, the base of the knob blackish. 
Abdomen black, densely gray pollinose and silvery white pilose, 
the pile longer and more erect on the sides of the first three segments. 
Second and third segments with a white posterior margin. Venter 
like the dorsum. Genitalia rather small, black, the upper forceps 
gray pollinose and with a narrow yellow margin; the hypandrium 
very short. Coxae all gray pollinose and white pilose. Femora 
black, gray pollinose and with rather short white pile. Kmees and 
most of tibiae and tarsi brownish yellow, the apices of tibiae and 
tarsi blackish. Bristles of the legs black. Wings hyaline, the veins 
