54 DIPTERA OF NORTH AMERICA. *[PART II. 



Bronze-green ; upper side of the thorax not very bright, dull ; abdomen 

 with a coppery-red reflection ; face whitish, sometimes more yellowish- 

 gray ; antenna? red ; cilia of the inferior orbit whitish ; cilia of the tegulae 

 black ; the fourth longitudinal vein with a stump of a vein. Long, 

 corp. 0.22. Long. al. 0.17. 



Syk. Dolichopus bifractus Loew, Neue Beitr. VIII, 19, 17. 



Bronze-green, but little shining. Face whitish, in not recently 

 ' excluded specimens generally more yellowish-gray ; in the J* it is 

 not much narrower than in the ?. Antennae red; their third 

 joint ovate, somewhat broad ; at the point of insertion of the arista 

 it is somewhat swollen and blackened ; its apical half is often 

 brownish. Arista with a very short but distinct pubescence. 

 Front bronze-green, but opaque, on account of a very delicate light 

 brownish-gray dust. Cilia of the inferior orbit whitish. Upon 

 the upper side of the thorax the ground color, altflough bronze- 

 green, is quite opaque, on account of a dense brownish-gray dust, 

 which in fresh, not denuded specimens, altogether conceals it. 

 Abdomen brighter metallic-green, in not recently excluded speci- 

 mens rather coppery. Coxa? and feet yellow ; the middle coxa? 

 up to the tip gray ; the front side of the fore coxa? sparsely beset 

 with delicate minute black hairs, glabrous towards the basis. 

 Hind femora before the tip with a bristle. Fore tarsi brownish, 

 only the last joints really black. Middle tarsi from the tip of the 

 first joint blackish ; the extreme tip of the hind tibia?, including 

 the whole hind tarsi, black. Cilia of the tegula? black. Wings 

 with a rather dark grayish tinge ; on the anterior margin and along 

 the veins generally somewhat brownish ; the fourth longitudinal 

 vein broken twice at right angles ; both angles sharp ; as an ex- 

 ception, the upper one sometimes slightly rounded ; at the lower 

 angle there is generally a stump of a vein, whilst the upper one 

 for the most part has none. 



Male. Lamella? of the hypopygium white, of moderate size, 

 rather rounded, on the upper and apical margin narrowly bor- 

 dered with black, on the latter somewhat jagged and fringed with 

 black bristles. Fore tarsi 1£ times the length of the tibia? ; first 

 joint somewhat longer than the second and third taken together ; 

 fourth and fifth joints black, somewhat flattened, the upper edge 

 of the fifth bearded with close black hairs. Hind tibia? plain, 

 their hind side not glabrous. 



Hab. Chicago. (Osten-Sacken.) Nebraska. (Dr. Hayden.) 



