Empididae. . 223 



somewhat strong bristles between the ordinary hairs. Balteres blackish 

 brown, the peduncle, except the base, yellow. 



Female. Quite agreeing with the male with exception of the 

 differences in the exterior genitalia. 



Length 4,3 — 5 mm. 



Cl. Zetterstedti has only recently been known as belonging to our 

 fauna, and it has only been taken on two occasions, at Hald near 

 Viborg on -^^/e 1910 (the author) and at Bangsbo near Frederikshavn 

 on -^V? 1909 (Th. Mortensen); in the former locality I took only one 

 single specimen, sitting on a stone at a rapidly running brook, among 

 specimens of Cl.rhynchops, this latter species being nmiierous; at the 

 latter place it was flying in great numbers over a small swiftly flowing 

 stream in the downs, and sitting on stones in it. 



Geographical distribution: — Northern and middle Europe down 

 into Austria; towards the north to middle Scandinavia. 



IV. Subg. Wiedemannia Zett. 



Stigma present, roundish; discai cell long, pointed at the apex; 

 anal vein not reaching beyond the anal cell. Glypeus horse-shoe- 

 shaped, separated from the epistoma; jowls descending much below 

 the eyes, and thus not separated from the cheeks. Acrostichal bristles 

 present; small bristles present in the dorsocentral ro vvs between the 

 long bristles. Scutellum with two bristles and small hairs. 



Tahle of Species. 



1. Stigma lying well before the base of the cubital fork, the 



curve of the radial vein below it rather large 5. bistigma. 



— Stigma lying above the base of the cubital fork, the curve 



of the radial vein below it small 6. rhynchops. 



5. Cl. bistigma Curt. 



1834. Curt. Brit. Entom. 513,2 {Heliodromia). — 1858. Loew, Wien. 

 entom. Monatschr. II, 243, 1. — 1862. Schin. F. A. I, 84. — 1881. Mik, 

 Verh. zool. bot. Gesell. Wien, XXXI, 327. — 1903. Kat. palaarkt. Dipt. II, 267. 



— Wiedemannia borealis : 1838. Zett. Ins. Lap. 559, 1 et 1842. Dipt. Scand. 

 I, 365, 1. — Wiedemannia juveniUs: 1842. Zett. Dipt. Scand. I, 362, 2. 



Male. Vertex and frons brownish, greyish along the eye-margin; 

 epistoma light grey; palpi black. Occiput grey, but the brown colour 

 continues from the vertex down the middle of the occiput as a broad 

 band. Jowls long, going far down below the eyes. Occiput with 

 black bristles above, white hairs below. Antennæ black. Thorax 

 olive-brown; on the disc there are about five long, black dorsocentral 



