Onesia. 



155 



cheeks with fine hairs, jowls black-haired. Occiput greyish pruinose 

 with yellow, downwards reddish hairs, and black hairs behind the 

 postocular bristles. Antennæ black, often more or less reddish at base, 

 third joint towards thrice as long as second. Arista densely, moderately 

 long-plumose in about basal half. Palpi yellow, Thorax black, some- 

 what bluish pruinose, with tliree not very distinct stripes, the median 

 broad, abbreviated behind, sometimes more or less divided into three. 

 Thorax is black- or brownish black-haired; three postsutural but 

 no præsutural intraalar bristle. Abdomen blue, sometimes greenish, 

 shining, with a slight whitish somewhat shifting pruinosity; a dark 

 middle stripe visible. Abdomen is 

 black-haired, third segment with mar- 

 ginal hairs which are more or less 

 bristly, especially in the middle; fourth 

 segment with a row of marginal bristles 

 and some of the hairs on the disc rather 

 strong. Genitalia somewhat large, upper 

 forceps strong, cleft to the middle, 

 curved slightly ventrally; hypopygium 

 on each side prolonged downwards into 

 a roundish lobe; inwards to these lobes 

 the arms of lower forceps issue, they 

 form strong hooks, curved upwards 

 with apex touching the apex of upper 

 forceps. Legs black; middle tibiæ with- 

 out ventral bristle; claws and pulvilli 

 strongly elongate. Wings a little or 

 somewhat brownish tinged; veins 



black; first posterior cell open, ending near apex of wing; apical 

 cross-vein concave; discai angle rectangular, sometimes with a quite 

 short veinlet; anal vein reaching near to margin. Squamulæ whitish, 

 the lower with black hairs above. Halteres yellowish to brown. 



Female. Similar; frons about as broad as the eye; middle tibiæ 

 with ventral bristle. 



Length 7 — 11 mm. 



O. sepulchralis is very common in Denmark and occurring 

 over the whole country in and at woods; the dates are ^*l^ — ^Viol 

 I have taken it in copula on ^/^ and ^^7. 



Geographical distribution: — All Europe; towards the north 

 to northernmost Scandinavia. 



Fig. 31. 



O. sepulchralis, forceps 

 in profile. 



