178 DIPTERA OF NORTH AMERICA. [PART II. 



5. C affinis Loew. % and £. — Viridis, nitens, tegularum ciliis nigris, 

 femoribus nigris viridi-inicantibus, summo anteriorum apice ex flavo 

 piceo. 



% . Oculis contiguis, tertio antennarum articulo subobliquo, tibiis anticis 



ex flavo piceis. 

 9 . Tibiis anterioribus ex flavo piceis. 

 Shining green, cilia of the tegulae black ; femora black with green lustre ; 



the extreme tip of the four anterior femora yellow-brownish. 

 % . Eyes contiguous ; the third joint of the antennae but little oblique ; the 



fore tibiae yellow-brownish. 

 9- The four anterior tibiae yellow-brownish. Long. corp. 0.09 — 0.10. 



Long. al. 0.10. 

 Syn. Chrysotus affinis Loew, Neue Beitf. VIII, 64, 4. 



Male. It is so much like the male of G. obliquus, that a state- 

 ment of the differences will be sufficient for its recognition. The 

 third joint of the antennae is visibly smaller and less oblique ; the 

 hind femora have upon the second part of their under side a 

 greater number of bristle-like black hairs ; finally the hair upon 

 the hind tibiae is much longer; the feet are considerably darker; 

 fore tibiae more yellowish-brown than yellow and towards their 

 tips distinctly dusky ; middle tibiae often almost brown-black, but 

 always with a yellowish-brown basis ; middle tarsi entirely black- 

 brown ; fore tarsi only near the basis of a pale brown color. I 

 have not discovered any other differences. 



Female. I have only a single female, which I think belongs 

 here. It resembles the female of the preceding species very much, 

 only the fore tibiae are more of a brownish-yellow color and dusky 

 towards the tip ; the middle tibiae are still darker than the fore 

 tibiae and the hind tibiae are like those of the male, black. The 

 third joint of the antennae is somewhat smaller than in the females 

 of G. obliquus. 



Hob. Middle States. (Osten-Sacken.) 



6. C vividllS, nov. sp. % . — Viridis, nitens, ciliis tegularum nigris, 

 femoribus nigris viridi-raicantibus, genibus tibiisque flavis, maris oculis 

 distantibus et costa alarum non incrassata. 



Green, shining, cilia of the tegulae black, femora black with green lustre, 

 knees and tibiae yellow ; in the male, the eyes separated and the costa 

 not thickened. Long. corp. 0.09. Long. al. 0.09. 



Metallic-green, bright, but on the upper side of the thorax with 

 a rather thick brownish-yellow dust and therefore more dull. The 



