42 Orthorrhapha brachycera. 



side, and both pairs with apical bristles; also tiie posterior metatarsi 

 with a few bristles. Wings slightly yellowish; veins brown; the axil- 

 lary lobe a little pronounced; the discai vein with a somewhat strong 

 bend, tiie iirst posterior cell rather broadly open. Squamulæ whitish 

 yellow, with a yellow fringe. Halteres yellow. 



Fig. 10. Wing of N. quadrifasciata d- 



Female. Epistoma very slightly broader than in the male. Thorax 

 yellow, in front of the scutellum a grey patch, which is sometimes 

 somewhat indistinct, and generally with indications of three greyish 

 stripes produced from the patch forwards. Postscutellum more or 

 less grey. Plem-a yellow, very sligthly greyish pruinose, with a small, 

 blackish spot as in the male. The four transverse bands on abdomen 

 are more or less deeply incised in the middle of the hind margin, 

 often so much as to be nearly divided into two spots. Legs simple. 



Length 3,5 to about 5,5 mm ; the male is longer than the female. 



N . quadrifasciata is somewhat common in Denmark; Copenhagen 

 in a garden, Ordrup Mose, Ermelund, Dyrehaven, Geel Skov, Tisvilde, 

 Sorø, and in Jutland at Sæby. My dates are ^^le—^^li. It may occur 

 in high grass on meadows, and in herbage and on foliage on humid, 

 shaded piaces, but especially on tree-trunks. Schiner says that only 

 the female is common, the male rather rare, but I think he has not 

 sought for it on trunks; I found both sexes in great number in Dyre- 

 haven on 2'/6 and ^''/(j; they were present on almost every tree-trunk 

 I examined, the males flying vertically along them ; on the latter date 

 many copulated pairs were taken. 



Geographical distribution: — Northern and middle Europe down 

 into France; towards the north to middle Sweden. 



± N.pallida Fall. 

 1823. Fall. Dipt. Suec. Dol. 21, 29 {Dolichopus) . — 1843. Zett. Dipt. 

 Scand. II, 611, 97 {Dolichopus). - 1862. Schin. F. A. I, 183. — 1903. 

 Kat. palaarkt. Dipt. II, 293. — Porphyrops ochraceus Meig. 1824. Syst. 

 Beschr. IV, 58, 29. — Medeterus ochraceus 1838. Meig. ibid. VII, 155. 



Male. Vertex and frons grey; postvertical bristles yellow, some- 

 times one or both black; the other bristles black. Epistoma narrow, 



