248 THE CANADIAN ENTOMOLOGIST. 



eyes and with a row of stouter hairs at the oral margin. Distance from the 

 oral margin to base of eye equal to about one-third the eye height. Sides of 

 face covered with silvery pollen ; bare ; narrowest width slightly less than the 

 length of the second antennal segment and equal to about one-third the dis- 

 tance between the vibrissae. Facial ridges bristly on lowest fifth. Facial de- 

 pression silvery pollinose, without any carina. Antenna in male reaching 

 lowest three-fourths of the face, all three segments black ; third segment in 

 male almost twice as long as the second. Arista thickened on basal two-fifths ; 

 the penultimate segment no longer than broad ; width of front in male at nar- 

 rowest point measuring slightly less than the length of the second antennal 

 segment, silvery pollinose becoming black at vertex; frontal vitta dull, dark- 

 brown, at narrowest point slightly wider than either side of front. No orbital 

 bristles in male ; the frontal bristles extending to base of third antennal segment. 

 Ocellar bristles present in male, directed forward. 



Thorax subshining, black, covered with grey pollen ; scutellum grey pol- 

 linose on a black ground tinged faintly reddish at apex. Three sternopleural 

 bristles and three to four post suturals ; scutellum with three marginal pairs of 

 machrochaetae and a terminal cruciate pair. Legs black, the middle tibiae with 

 two or more bristles on the front side near the middle, the hind tibiae without 

 a comb-like row of bristles on the outer side. Wings hyaline ; R^^^ (third 

 vein) with a group of three to five bristles at the base on both the upper and 

 lower surface. Tegulae white. 



Abdomen subshining; silvery pollinose on a black ground. Discal bris- 

 tles present on the second, third and fourth abdominal segments ; a pair of 

 median marginal machrochaetae also present on each of these segments. The 

 fifth tergum very narrow and rather indistinctly marked off by a suture from 

 the sixth tergum with which it is united. Sixth abdominal segment almost 

 as long as the fourth and forming a conspicuous genital segment. 



The black genitalia of the male are characterized by there being a short 

 median keel situated on the basal part of the inner forceps (valvae internae), 

 and by the fact that this keel is not concave in profile on either of its two mar- 

 gins. 



The horseshoe-like indenture of the fifth sternite extends rather less 

 than half way into the sternite. 



Described from eleven males taken at Franconia N.H., Stickeen River, 

 B. C. (type locality), and Savary Island, B. C, by Messrs. C. H. T. Townsend, 

 Wickham and R. S. Sherman. 



Type in the Canadian National Collection, Ottawa. The paratype. No. 

 24354, from Franconia in the U. S. N. M., Washington, D.C. 



Ernestia arcuata sp. 11. 

 Head at vibrissae about as thick as at base of antennae ; vibrissae far 

 above the oral margin. Palpi usually yellow at the tip and infuscated basally, 

 occasionally black. Eyes hairy, cheeks (below the eyes) white pollinose on a 

 black ground, subshining on the lower part that is covered with black hairs, a 

 row of stouter hairs at the oral margin. Distance from the oral margin to base 

 of eye equal to about one-third the eye height. Sides of face covered with 

 silvery pollen; bare; narrowest width in male slightly less than the length of 



