THE CANADIAN ENTOMOLOGIST 227 



Thorax subshining, black, covered with gray pollen; scutelliim gray 

 pollinose on a black ground that becomes faintly rufous toward the apex. Three 

 sternopleural macrochaetae and typically four dorsocentrals, although both sets 

 are subject to considerable variation; scutellum with four marginal pairs of 

 macrochaetae and with an apical 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. R4+5 

 (third vein) with a group of two to five hairs both above and below at the 

 junction with R.,,.,. Bend of Mj+. destitute of an appendage. Radio-medial 

 cross vein cloudy. I'egulae white. 



Abdomen subshining; silvery pollinose on a black ground. No discal 

 macrochaetae present on the second abdominal segment, but a pair on each of 

 the following segments; marginals present on the second, third and fourth. 

 The hind margin- of the third tergite not arcuate even in the male. The fifth 

 tergum in the male marked ofif distinctly by a suture from the fourth and 

 about one-fifth as long as the fourth. The sixth and seventh abdominal seg- 

 ments forming genital segments that are noticeably smaller than in B. ampelus 

 Walker and the other species described in this paper. 



Genital segments of the male black. The basal part of the outer forceps 

 not covered by a leaf-like expansion. The basal part of the inner forceps 

 without a median keel-like projection ; the distal part forming a straight, 

 bayonet-shaped blade. 



The indenture in the last sternite of the male extends to the base of 

 the sternite so that the sternite is split longitudinally into two halves. 



Redescribed from six males and four females in the U.S.N.M. collection 

 and in the Canadian National collection. Collected from the White Mountains, 

 Franconia, N.H. ; Mandan, N.D. ; Cranbrook, B.C. ; and Lillodet, B.C. 



Ernestia (Meriania) nigrocornea sp. n. 



Description of Male. Head at vibrissae about as thick as at base of 



antennae, vibrissae far above the oral margin. Palpi reddish. Eyes hairy. 

 Cheeks (below the eyes) white pollinose on a black ground with black hairs 

 on the subshining part, coming nearly up to the 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-half the eye height. Sides of face silvery pollinose ; bare, except 

 for a few sparse hairs, particularly at the upper part; narrowest width equal 

 to about twice the length of the" second antennal segment. Facial ridges bristly 

 on lowest third. Facial depression silvery polHnose without any carina. An- 

 tennae reaching lowest three-fourths of the face, all three segments black or 

 very dark-brown in color ; third segment about twice as long as the second. 

 Arista thickened on basal half; the penultimate segment scarcely longer than 

 broad ; width of front at narrowest point measuring about twice the length 

 of the second antennal segment ; silvery pollinose ; frontal vitta dull, dark- 

 reddish brown, at narrowest point measuring almost half the width of front 

 at vertex. No orbital bristles; the frontal bristles extending nearly to the 

 base of the third antennal segment. Ocellar bristles well-developed and 

 proclinate.. 



Thorax subshining. black, covered with gray i)ollen ; scutellum gray 



