326 THE CANADIAN ENTOMOLOGIST. 



yellow pile, somewhat brighter coloured than that on the mesono- 

 tum and scutellum. 



Legs entirely black; claws ferruginous on the thickened basal 

 portion, black distally; pulvilli yellowish brown. 



Wings with the venation similar to II. mystacea, the apical cell 

 at extreme tip of wing. Last section of the fourth vein very 

 slightly less upward bent than in that species. Basal portion of 

 the wing to the tip of the subcostal vein and the base of the apical 

 cell bright yellow, the veins in that portion ferruginous yellow; 

 portion beyond light grey, clouded with brown in the costal region 

 and along the veins, the veins themselves black. Tegulae yellow, 

 with deep yellow margin and yellow ciliation. 



Length: Body about 14 mm., wing 12.5 mm. 



Two specimens: High River, Alberta (T. Baird) ; Glacier Park, 

 Montana, June 28, 1912 (J. R. Parker). Type and paratype in 

 the collections of the U. S. National Museum and the Montana 

 Agricultural College. 



The specimen recorded by Prof. Hine from Lake Timagami, 

 Ontario, under the name Mesembrina mystacea (Can. Ent., vol. 39, 

 p. 98; 1907), evidently belongs to the species here characterized. 

 The present form differs from mystacea particularly in the colora- 

 tion of the thoracic vestiture and of the tegulae, that species having 

 the vestiture on the posterior part of the mesonotum and on the 

 scutellum black, and furthermore dark brown tegula? with black 

 ciliation. II. solitaria agrees much more closely with H. decipiens. 

 That species also has the mesonotum and scutellum clothed en- 

 tirely with yellowish pile and the tegulae yellow. In decipiens the 

 last two abdominal segments are clothed with yellowish white pile 

 and the hairs on the cheeks are dirty white. The whitish abdominal 

 hairs, as against their deep yellow colour in our form, can hardly be 

 considered a specific character, since Loew (1. c.) has already 

 pointed out that the colour of this pile is variable in H. mystacea; 

 the difference in the colour of the cheek vestiture, being black in 

 our species, must, however, be considered specific. 



