82 DIPTERA OF NORTH AMERICA.' [PART II. 



not very broad, pointed at the end, with longer hairs than in most 

 of the other species ; the arista is inserted in its middle and has 

 a rather indistinct pubescence. Cilia of the inferior orbit black. 

 Scutellum with the usual two bristles ; otherwise I cannot per- 

 ceive any hairs upon its surface. Feet black. Trochanter with 

 the extreme tip of the first joint of the coxa, tip of the femora, 

 the tibiae, and the roots of the four anterior tarsi, yellowish, but, 

 on account of the density of the short black hairs, of pretty dark 

 appearance. The hind side of the hind tibia? is clothed towards 

 its end with dense black hairs, so that it appears pretty black ; the 

 root of the hind tarsi is brown. Cilia of the pale yellowish tegulae 

 black. Halteres yellow-whitish. Wings gray-blackish, a little 

 darker towards the anterior margin. The small lamellae of the 

 hypopygium are black. 



Hab. English River. (Kennicott.) 



4. Cr. Ibai'toatllfius Loew. % and 9 . — Atro-virens, pedibus nigris, 

 trochanteribus, genibus, tibiis (excepto tamen posticarura apice) tarso- 

 rumque anteriorum basi iiavicantibus, alis ex cinereo-hyalinis, infera 

 faciei parte nigro-pilosa. 



Black-green ; feet black, trochanters, knees, tibia? (with the exception of 

 the tip of the hind ones) and the root of the four anterior tarsi yellowish, 

 wings grayish-hyaline, the lower part of the face with black hair. Long. 

 corp. 0.12. Long. al. 0.12—0.13. 



Syn. G ymnopternus barbatulus Loew, Neue Beitr. VIII, 29, 4. 



Dark black-green, face gray-white, the inferior part of it some- 

 what swollen transversely, and with small sparse black hairs. 

 Antennae entirely black, their third joint broad, pretty rounded, 

 and only with short, scarcely perceptible hairs. Pubescence of 

 the arista extremely short, hardly perceptible. Front dark me- 

 tallic green ; the dust on its surface can only be perceived in an 

 oblique direction. Cilia of the inferior orbit black. Besides the 

 usual two bristles upon the scutellum, there are a few short, 

 extremely slender, and therefore scarcely perceptible hairs. Feet 

 black; the tip of the first joint of the coxaa, the trochanter, the 

 tip of the femora, the tibiae, and the root of the four anterior 

 tarsi yellowish, the tip of the hind tibiae to a moderate extent 

 black. The cilia of the yellow tegulae black. Halteres white- 



