256 DIPTERA OF NORTH AMERICA. [PART IV, 



stripes on this grayish ground ; halteres brown ; feet ferruginous ; 

 tips of the femora and of the tibia3 brown ; tarsi brown. Abdomen 

 brown, shining; male forceps tawny; its structure like Tab. IV, 

 fio-. 28 ; ovipositor ferruginous, tawny at the basis. Wings 

 brown, clouded along the veins ; stigma still darker brown ; four 

 posterior cells; first submarginal cell but little more than half the 

 length of the second ; the marginal cross-vein close by the inner 

 end of the first submarginal cell. 



Eab. Berkeley Springs, Virginia ; Washington, D. C. I had 

 nine male and one female specimen when I first described this 

 species. I possess, moreover, two males from Yirgiuia and a 

 female from Ohio, the coloring of which is very like that of E. 

 longicornis, gray with brownish stripes on the thora.x ; the wings 

 are only slightly tinged with brownish ; the knob of the halteres 

 is dark brown ; the first submarginal cell is short, with the cross- 

 vein close by its inner end. The difference in the coloring from 

 the typical specimens of U. fuliginosa is very considerable ; but 

 I fail to discover any essential differences. 



Gen. XXXIV. PEXTHOPTERA. 



Two submarginal cells ; four or five posterior cells ; a discal cell ; the 

 subcostal cross-vein at the very tip of the auxiliary vein ; the first sub- 

 marginal cell shorter than the second ; stigma very small, occupying but a 

 small portion of the interval between the tip of the auxiliary vein and the 

 marginal cross-vein ; wing-veins distinctly pubescent. Gibbosity on the 

 front comparatively small; antennae six-jointed in the male, sometimes 

 much longer than those of the female, sometimes of the same length ; 

 antennae of the female ten-jointed, comparatively short. Tibiae with short 

 spurs at the tip ; ungues small ; empodia small, but distinct. Male forceps 

 like that of Eriocera. 



This genus has been proposed by Dr. Schiner for the European 

 species P. chirothecata Scop, and cimicoides Scop., with the first 

 of which the North American P. alhitarsis is most unmistakably 

 allied. Although these three species have all the characters of 

 Eriocera, it is easy to perceive peculiarities in their general 

 appearance and their coloring, which justify their separation. 

 The wings are more elongated, the wing-veins seem to be more 

 slender, less dark in coloring ; the cells in the apical portion of 

 the wing are longer, the veins enclosing them less diverging, more 

 parallel, and much more distinctly pubescent ; the fringe of hairs 

 along the posterior margin of the wings is longer ; the stigma is 



