Evibrissa. 111 



Of this species I know only tlie female. Frons nearly as broad 

 as the eye, almost not protriiding. Orbits and cheeks very narrow, 

 and likewise jowls. Head silvery, but the orbits black above; the 

 broad frontal stripe velvet black. High above two small forwards 

 directed orbital bristles. Orbits bare, jowls with few small black 

 hairs. Occiput whitish grey, black above along the eye-margin, with 

 whitish hairs. Antennæ blackish, third joint fuUy thrice as long as 

 second; arista bare. Palpi blackish brown. Thorax black, somewhat 

 greyish or bluish grey pruinose, with four black, rather indistinct 

 stripes, the median abbreviated behind. Thorax with short black 

 hairs; no posthumeral but two intraalar bristles. Abdomen reddish 

 yellow, a narrow base and the apex black, from the base a middle 

 spot is prolonged a little backwards and the third segment has a 

 black middle spot at hind margin; the black apex includes fifth and 

 fourth segment, but the latter has the lateral front corners yellow. 

 Abdomen has short, black hairs and a pair of small marginal bristles 

 on each segment. Sixth segment bent in under venter, with a large, 

 downwards directed, furcate process, and the last segment is cleft 

 into two large claws. Legs black with few and moderate bristles; 

 middle tibiæ with a ventral bristle; tarsi with the three last joints 

 somewhat broad. Wings brown with brown veins; first posterior cell 

 open, ending quite near apex of the wing; angle on discai vein obtuse 

 but corner sharp; posterior cross-vein strongly sinuate. Squamulæ 

 white with yellow margin. Halteres brown. 



Length 8 mm. 



E. ohscuripennis is very rare in Denmark, I know only one 

 specimen, a female, taken at Sorø in September 1849 (Jacobsen); 

 this is the specimen mentioned by Zetterstedt. 



Geographical distribution: — Europe; not known north of 

 Denmark. 



10. Besseria R. D. 



Small species of black and red colour. Head a little broader 

 than thorax, convex behind and somewhat pufTed out below, slightly 

 higher than long. Frons broad in both sexes, broadest in female, 

 slightly protruding. Jowls somewhat broad, but horizontal and 

 thus slightly descending. In both sexes small ocellar and inner vertical 

 bristles, in female no or very indistinct orbitals. Behind postocular 

 bristles some black hairs above. Frontal bristles reaching to the 

 insertion of antennæ, all crossing in both sexes. Cheeks bare or only 



