SYNOPSIS OF NORTH AMERICAN SYRPHID^. 175 



base of the tibia?- fuscous. Wings pure hyaline, veins fuscous-black, 

 veins of the disk in the female clouded with blackish. 

 Translation from original, compared with the types. 



Eristalis obscurus. 



Eristalis oi'^eHrits Loew, Centur., vi, 67. 



Habitat. — Eed Elver of the North (Loew) ! 



$ . Length 10 to ll'^"". Bronze-black, shining, clothed with rather long, 

 dilutely lutescent-cinereous pile; front broad, above black pilose; eyes 

 pilose. Antennae reddish-ferruginous, first two joints black; arista 

 pilose ; face, except the usual stripes, yellowish-red, white pollinose and 

 white pilose. Scutellum brown, black near the base. Each abdominal 

 segment, except the first, with a posterior black fascia, not emarginate, 

 and with a very slender posterior yellow margin. Legs black ; tip of all, 

 and base of hind, femora, the basal third of front and hind tibise, middle 

 tibise, except the tip, and the first two joints of all the tarsi, light yel- 

 lowish. Wings pure hyaline, veins of the disk clouded with fuscous. 



Similar to E. dimidiatus. Bronze-black, shining, clothed with rather 

 dilutely lutescent-cinereous pile. Front broad, concolorous, abov^e black 

 pilose, a median spot on the front margin reddish, the lateral margins 

 in front white pollinose. Face yellowish-red or red, white pollinose 

 and white pilose, median stripe black, rarely pitchy, oral margin and 

 the cheeks always black. First two joints of the antennae black, third 

 red or ferruginous-red, rarely obscurely fuscous ; arista pilose. Thoracic 

 dorsum neither striped nor fasciate. Scutellum pitchy or brown, near 

 the base always metallic black. First segment of the abdomen glaucous, 

 white pilose; second segment with two velvety fasciae, separated by a 

 shining fascia which is much delated on the sides ; the posterior margin 

 yellow. In the following segments, besides the very slender yellow hind 

 margin, with a posterior opaque black fascia, that on the third segment 

 velvety, on the remaining segments moderately shining. Pile on the 

 posterior part of each segment black, on the front portions in great part 

 cinerescent. Legs black, pallidly pilose ; hind femora slender, near the 

 base yellow; tip of all the femora, basal third of front and hind, and 

 the middle tibiae except the tip, and the first two joints of all the tarsi, 

 light yellow, the second joint near its tip blackish. Wings pure hyaline, 

 the disk clouded with fuscous, stigma and immediate base fuscous. 



Translation from the original, compared with the type at Cambridge* 



Eristalis inornatus. 



Eristalis inornatus Loew, Centur., vi, 68. 

 Hahitot.—Ued Eiver of the North (Lw.)! 



2 . Length 13"". Submetallic black, shining, clothed with rather 

 long lutescent pile; front broad, near the ocelli black pilose, but the 

 vertex itself with luteous pile. Eyes pilose. Antennae reddish-ferru- 

 ginous, the first two joints black; arista pilose. Face, except the usual 



