94 DIPTERA OF NORTH AMERICA. [PART 111. 



only. If the want of a dark coloring at the basis of the first 

 basal cell be singled out as a characteristic feature, the supposition 

 suggests itself that the species is identical with R. flavimana, 

 which also partakes of this character ; the shortening of the first 

 two crossbauds, as well as the data concerning the size and col- 

 oring of //. metallica, do not contradict such an assumption ; 

 even the statement about the coloring of the feet could be applied 

 to unusually pale specimens of R. flavimana, although I ha\3 

 never met with specimens of this degree of paleness. Hence, 

 it appears not improbable, although far from certain, that Herina 

 metallica is identical with R. flavimana. 



6. It. Illicans n. sp. 9 • — Speciebus prsecedentibus minor, Isete jeneo- 

 viridis, nitida, pedibus omnibus luteis, fasciis alarum fusco-uigris. 



Smaller tban the preceding species, metallic-greeu, shining ; all the feet 

 saturate-yellow ; the crossbauds on the wings brownish-black. Long, 

 corp. 0.13—0.15 ; long. al. 0.13. 



Not reaching the size of R. variabilis and perceptibly smaller 

 than the other preceding species ; of a metallic-green, bright 

 and shining coloring. The front, the lateral stripes on the face 

 and the lower part of the occiput of a reddish-yellow, seldom of 

 a brownish-red coloring ; antennae, as far as the basal third or 

 the middle of the third joint, reddish-yellow ; beyond that, 

 brown. The abdomen shows a diluted, half-pellucid, reddish 

 crossband at the place where the first and second segments are 

 soldered together ; in some cases this band is wanting. Coxae 

 and feet saturate-yellow, the former sometimes more brownish- 

 yellow ; the tarsi, towards their tips, are strongly infuscated. 

 The picture of the wings, in its design, is not unlike that of 

 R. viridulans, but is rather brownish-black than deep black ; the 

 dark crossbands are a little narrower, especially the first and 

 second, so that the hyaline interval between them is compara- 

 tively broader, almost equal in breadth to the interval between 

 the second and third bands (in R. viridulans the first interval is 

 considerably narrower than the second) ; the first and second 

 crossbands stop about the middle of the interval between the 

 fourth and fift'h longitudinal veins; however, single specimens 

 occur in which they are shorter ; in other specimens they reach 

 very near the fifth vein ; the third band, towards its end, is per- 

 ceptibly narrowed. The second section of the fourth longitu- 



