SYNOPSIS OF NORTH AMERICAN SYRPHID^. 187 



S , 9 . Length, 11 to 12""". Face with a short deep convexity behjw 

 the antennae to tip of tubercle, thence receding in a nearly straight line 

 to the oral margin ; median stripe and cheeks bare, black and shin- 

 ing; the sides of the face concealed beneath dense whitish-yellowish 

 pollen and pile. Antennae black, the arista reddish-yellow. Front in 

 both sexes very b'road, in the male narrowed a little before the ocelli, 

 in the female broader, only a little narrowed toward the vertex ; the 

 ocelli in both sexes are remote from each other ; the color is shining 

 black above and in the middle below near the antennae, yellowish pol- 

 linose on the sides and across broadly below the ocelli ; the pile is j^el- 

 lowish, except across below the ocelli, and at the vertex, where it is 

 black. Dorsum of thorax grayish-olivaceous-black, but little shin- 

 ing, leaving in the middle part six slender opaque black lines, that 

 inclose three slender whitish, strii)es, all of which are obsolete before 

 the scutellum ; the outer black lines are a little dilated before, and inter- 

 rupted at the suture ; in addition, on each side behind there is a slender 

 opaque black stripe,which runs from the scutellum towards the outer end 

 of the suture. Pile of thorax yellowish, rather ahundant ; more whitish 

 on the pleura;. Scutellum obscurely reddish on the outer part. Abdo- 

 men broad, not extending beyond the wings; in the female black, the first 

 segment shining, with an opaque spot on each side; second segment on 

 each side with a broad, nearly opaque spot, extending across the front 

 margin, bordered behind on the sides by a light reddish-yellow spot 

 that reaches from the anterior angle to the middle of the segment, ex- 

 tending as a narrow whitish pollinose cross-bamd inwards and separated 

 from that of the other side by a not very broad opaque black interval; 

 ]iosterior part of the second segment shining, the narrow hind margin 

 gray, as on the following segments ; third segment with two slender, 

 gray pollinose spots, beginning at the front angles and curving back- 

 wards, inwards, and then a little forwards, broader at the inner ends, 

 and separated from each other by a narrow, partially opaque, interval ; 

 in front of these spots the black is sub-opaque, elsewhere shining; fourth 

 segment similar, but the spots more slender and nearly touching the 

 front margin on their inner ends, thus leaving on each side in front a 

 small, opaque, semi-lunar spot. In the male the abdomen is in large 

 part dark-reddish ; on the third segment the color is almost wholly red, 

 brownish behind, the gray spots nearly obsolete, leaving only the be- 

 ginnings and tips ; the fourth segment like that in the female, but the 

 opaque parts are more brown, and the shining part red. Hypopygium 

 wholly reddish. Legs black ; the base and tip of four front tibiaj nar- 

 rowly red, the hind tibite variegated black and red ; all the tarsi more 

 brown; metatarsi of the hind feet distinctly swollen. Wings nearly 

 hyaline. 



Six male and seven female specimens, California (O. T. Baron), Wash- 

 ington Territory (H. K. Morrison). 



