254 Journal New York Entomological Society. [Voi. xxi. 



Sections of the fourth vein i : 4, of the fifth vein subequal. (Eur.;* Col.*) 



nigripes Meigen, sens. str. Schiner. 



27. Second section of the costa about three times as long as the third section; 



fourth vein diverging from the third and ending much beyond the 

 wing-tip ; discal cell large, the segments of the fifth vein 3:2; wings 

 broad; third antennal joint very small, the arista long, slender and 



pubescent 28. 



Second section of the costa about four times as long as the third section ; 

 arista short, stout at base, and apparently bare 29. 



28. Front broader, about one third the width of the head, brownish ; abdomen 



black; frontal bristles fine. (D. C, N. J., Mass., Ont., 111.,* Wise.,* 



La.,* Kans., Tex.*) parvicornis Loew. 



Front narrower, less than one third the width of the head, the frontal 

 lunule with a rounded white spot; abdomen black, in the (^ the last 

 few segments yellowish; frontal bristles robust. (Pa., Mass.,* N. H., 

 Fla., 111.,* La.,* S. Dak.*) terminalis Coquillett. 



29. Discal cell large, the segments of the fifth vein 3:2; fourth vein ending 



far beyond the wing-tip, its segments about 2:5; four dorsocentrals ; 

 thorax lightly pollinose. (Eur. ;* Id.,* Wash.,* Ore.*) . .reptans Fallen. 

 First section of the fifth vein not greatly longer than the outer section; 

 tip of the wing near the middle of the first posterior cell, the third 

 and fourth veins subparallel 3°. 



30. Discal cell smaller than usual, the basal section of the fifth vein much 



shorter than the outer section ; the sections of the fourth vein about 

 I : S ; root of the wing and the notopleural suture narrowly whitish ; 



at least the front knees yellow 31. 



Basal section of the fifth vein longer than or subequal to the outer section ; 

 the sections of the fourth vein about 1:3 32. 



31. Scutellum broadly yellow in the middle; interfrontalia yellow. (Wash.*) 



interfrontalis n. sp. 

 Scutellum black ; interfrontal sutures often striped with yellow above, but 

 otherwise the front is black. (Eur.;* Mass.,* Id.,* Wash.*) 



luctuosa Meigen. 



32. A narrow yellow sutural line along the sides of the thorax, expanding be- 



neath the root of the wing; knees, front tibiae and the tarsi more or 

 less yellowish; frontal lunule white-pollinose ; wings broader. (Pa., 



' N. J., Mass.,* Wise, 111.,* La., Wash.*) angulata Loew. 



Thorax not marked with a lateral yellow line ; legs generally darker ; front 

 opaque black; wings narrower. (Nebr., Mass.,* D. C, Va., Fla., W. 

 Ind., La., Tex., 111.,* Wise.,* S. Dak., Wash.,* Alaska.) . .nepfw Loew. 



33. Front broader than long, black, but yellow below ; antennas entirely black ; 



penultimate section of the fourth vein about one third as long as the 



ultimate section of the fifth vein. (W. Ind.) anthrax Williston. 



Front mostly yellow ; base of the antennae yellowish ; penultimate section of 

 the fourth vein two thirds as long as the ultimate section of the fifth 



