56 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. 62. 
berta, June 20 to 28 (R. N. Chrystal); Banff, Alberta, August 7 (N. 
B. Sanson); Prince Albert, Saskatchewan; Corcross, Yukon Territory, 
July 25 (A. P. Hawes); Kasio, British Columbia [all Canad. coll.]; 
Vancouver, British Columbia, June 8; Cranbrook, British Columbia, 
July 26; Penticton, British Columbia, July 7 (EZ. M. Anderson), [all 
R.S. Sherman]; Fort Rae, Mackenzie, July 27 (E. R. Preble), [Biol. 
Surv.]. 
New York: North Elba, July [Amer. Mus.]; Ithaca, May; Adiron- 
dack Mountains, Axton, June 12 (A. D. MacGillvary), [Harrisb. coll.]. 
Pennsylvania: Rockville, May 10 [Harrisb. coll.]. 
Minnesota: St. Anthony Park, September 27 and July 18 [U. Minn.]. 
Michigan: Agricultural College, May 11 [Cornell]. 
Colorado: Manitou, August 18 (Osten Sacken), [M. C. Z.]; Denver, 
June 16 (J. S. Hine), [Hine]. 
Montana: GallatinCounty, July 18; Judith Basin, June 6; Boseman, 
June 17 to July 3 [all Mont. Exp. Sta.]. 
Washington: Pullman, June 9 to August 2 (Cole); Molson, June 8 
(A. C. Burrill), [Cole]; Forks, Clallam County, July 1 (E. P. Van 
Duzee), [Cal. Acad. Sci.]. 
Oregon: Multnomah Falls, September 30 (Cole), [Cole]. 
California: Muir Woods, May 9 (E. C. Van Dyke), [Cal. Acad. Sci.]. 
PSILOCEPHALA ARGENTIFRONS, new species. 
Plate 6, fig. 64; plate 8, figs. 94 and 100; and plate 13, fig. 174. 
Male.—Length 8.5mm. Resembles P. munda in general appear- 
ance. Head black, the frons silvery gray pollinose, the upper corner 
of the triangle dull biack. (Fig. 64.) Antennae rather short, the 
third joint longer than the first (fig. 94), black, with black bristles 
and pile; a few black hairs above each antenna. Face silvery white 
pollinose. Occiput, white pollinose and pilose. Proboscis and palpi 
black, white pilose; a few black hairs at the lower corner of the eye; 
bristles of occiput black and strong. 
Mesonotum, pleura, and scutellum black, gray pollinose; two 
whitish gray longitudinal vittae on the dorsum of thorax, which is 
blackish gray, paler on the margins and before the scutellum; erect 
fine black pile in the median portion of the dorsum, white around the 
margins; pleura and coxae gray poillinose and white pilose; bristles 
of thorax black; middle of scutellum, space between thoracic vittae, 
and lateral margins of mesonotum semishining. Halteres blackish, 
the knob gray pollinose. 
Abdomen black, silvery gray pollinose, the silvery white pile longer 
on the first three segments, shorter and reclinate on the fourth, fifth, 
and sixth; seventh segment and the genitalia black pilose; second 
segment with a white posterior margin. Genitalia blackish, the upper 
forceps much larger than the hypandrium. (ig. 100.) Legs entirely 
