124 Orthorrhapha brachycera. 



Male. Of somewhat slender shape. Vertex and frons green. 

 Epistoma narrow, narrower than in acuticornis, white, somewhat yel- 

 owish, especially upwards. Palpi white. Occiput green, greyish pruinose, 

 postocular bristies white below, black above. Antennæ much elongated, 



Fig. 38. Antenna of D. longicornis, c?, from the inside. X 65. 



ahiiost twice as long as the head, third joint long, the apical part 

 attenuated, pointed and turned upwards with the apex ; it is distinctly 

 haired; the arista is inserted behind the middle; the antennæ are 

 yellow, the two basal joints black above and the third joint black 

 above and with the apical part black. Thorax duUish green, some- 

 times more æneous, and there may be a golden or coppery middle 

 stripe; it is distinctly greyish or brownish pruinose, slightly shining; 

 scutellum finely yellow pubescent; postscutellum almost quite grey. 

 Pleura greenish, grey pruinose; propleura with a few, fine and pale 

 hairs and a black prothoracic bristle. Abdomen green or golden 

 green, often with coppery reflexes; there are narrow, dark hind mar- 

 gins to the segments; abdomen is clothed with short, black hairs, 

 and has somewhat short hindmarginal bristles, a little longer on the 

 first segment; down the sides there may be some yellowish hairs. 

 Venter greenish grey, slightly pale-haired. The hypopygium is quite 

 different from that in acuticornis; it is black or æneous black, greyish 

 pruinose; eighth segment with black hairs; there are slightly pro- 

 jecting, somewhat broad posterior ventral lobes with a little point at 

 the upper apical corner, and with a very fme hair; the middle lobes 

 a little projecting; the inner lamellæ of usual shape, curved down- 

 wards, the median thin, the lateral dilated, with some spines; the 

 outer lamella somewhat ovate, white, with a not quite narrow, blackish 

 margin along the ventral, apical and the half part of the dorsal edge; 

 at the end there are some teeth with black, curved hairs, and dor- 

 sally to these two strong hairs ; the teeth decrease in length towards 

 the ventral margin, which has long, paler hairs, and on the inner 

 side inwards curved, pale hairs. Legs yellow; front coxæ whitish 

 pruinose anteriorly, middle coxæ grey, with yellow apex, hind coxæ 

 yellow, only with a small grey spot outwards, sometimes stretching 

 more or less towards the base; front tarsi brownish towards the end; 



