92 DIPTERA OP NORTH AMERICA. [PART III. 



5. R. flaTimana n. sp. % $>.— (Tab. VIII, f. 7.) Viridi-nigra, 

 vel nigro-chalybea, pedibus anticis luteis, posterioribus semper ex 

 parte, plerumque maxima ex parte, nigris vel fuscis. 



Greenish-black, or more bluish-black ; the front feet dark-yellow, the 

 hind feet partly, and usually for the most part, black or bluish-brown. 

 Long, corp. 0.16 ; long. al. 0.14. 



Syn. ? Herina metallica v. d. Wulp. Tijdschr. voor. Ent. x, p. 154. Tab. 

 V, f. 10. 



Yery like R. viridulans, but easily distinguished by its smaller 

 size and the paler, although very variable, coloring of the feet. 

 Metallic blackish -green or almost blackish-blue. Head shining 

 black ; occiput of a metallic greenish-black ; front dusky reddish- 

 brown, often blackish-brown, on each side near the orbit with a 

 very narrow border of white pollen. The first two antennal 

 joints brownish-red, the third blackish-brown or black. The 

 coloring of -the abdomen towards the tip, in the male, verges 

 more on bronze-black ; the only female which I can compare has 

 no trace of this color. Fore coxae and tibiae yellowish ; the upper 

 side of the femora and the basis of the tibiae very seldom show a 

 trace of infuscation. The four posterior feet have the coxae, 

 femora, and tibiae black or brownish- black, the tarsi yellow. 

 The above-mentioned female has the tip of the middle femora 

 and the middle tibiae, with the exception of the dark-brown basal 

 third, of a brownish-yellow color; the tips of the tarsi in this 

 specimen are hardly infuscated at all, while the male specimens 

 have the three or four terminal joints of the front tarsi and the 

 last three or four joints of the middle and hind feet some- 

 what dark-brownish. Halteres brownish-black. The picture of 

 the wings recalls, in design and coloring, that of R. viridulans, 

 only the crossbands are a little narrower; in general also the 

 second, and especially the first, reach less near the fifth longitu- 

 dinal vein ; the black coloring, which is apparent on the root of 

 the anterior basal cell of R. viridulans, is wanting in R. Jlavi- 

 mana, and this affords a good character for distinguishing the 

 latter species from those allied to it. 



Hab. Nebraska (Dr. Hayden). 



Observation 1. — I possess a male, the four posterior feet of 

 which, with the exception of the hind tibiae, are yellow ; it is 

 also distinguished by the color of the antennae, which are reddish- 

 yellow as far as beyond the middle of the third joint, and by the 



