Gymnosoma. 107 



Male. Frons above a little narrower than the eye, a little protrud- 

 ing. Orbits and cheeks deep yellow, jowls white or yellowish white. 

 Frontal stripe red or brown. Frontal bristles fine. Orbits with small 

 black liairs in the whole length or only above; jowls white-haired 

 with a few black hairs anteriorly. Occiput whitish grey, along the 

 margin above black and shining; it has whitish hairs and some few 

 black above. Antennæ black, long, third joint somewhat longer than 

 the long second; arista thickened in aboiit basal half, apparently 

 bare. Palpi black. Thorax black, shining, but deep yellow pruinose 

 on front half to a little behind the suture, and with four brownish 

 black stripes, the median narrow, the lateral only forming spots and 

 none of them reaching behind the suture or only a little. Scutellum 

 with a pale yellow spot on utmost apex. Pleura grey pruinose. Thorax 

 black-haired. Abdomen yellow, base of second segment black, the 

 colour in the middle prolonged to the hind margin, and a roundish 

 median apical spot on third, fourth and fifth segment. Abdomen 

 densely and short black-haired, without bristles. Upper forceps 



Fig. 15. Wing of G. rotundatuin ($ . 



short, triangular with a beak-like apex. Legs robust, with anterior 

 femora thickened; the legs are black and shining, black-haired, but 

 without distinct bristles. Wings brownish tinged, most towards 

 anterior margin, the base yellow; veins brownish black; first posterior 

 cell short petiolate or closed at margin, ending a little before apex 

 of wing; angle on discai vein more or less rounded. Squamula (thoracic) 

 and balteres yellow. 



Female. Similar; frons somewhat broader and frontal bristles 

 stronger; orbits black, shining and with stronger hairs along eye- 

 margin; cheeks and jowls white. Thorax only yellow pruinose on 

 humeri and at the sides to the suture. Abdomen with the spots on 

 third and fourth segment broadened along the hind margin to broadly 

 triangular spots and continuous along the middle and with the spot 



