Aphiochaeta. 411 



with two approximate bristles below near base, and besides with 

 small hairs; anal tube somewhat small, yellow. Legs yellow, hind 

 femora somewhat darkened at apex, the hairs below the basal half 

 sparse and somewhat long; bristles on hind tibiæ small, but distinct. 

 Wings more or less yellowish or brownish yellow, veins brown or 

 pale brown; costa about 0,37 of the wing-length, costal divisions 

 about as 4 — 1 — 1; third vein a little thickened, and bent a little sud- 



Fig. 121. Wing of A. halterata S- 



denly upwards at apex, angle at fork somewhat small; costal cilia 

 long; fourth vein straight or nearly in its first two thirds, then curving 

 upwards and again distinctly recurved in the apical part. Halteres 

 yellow. 



Female. Similar; antennæ smaller; venter likewise conspicuously 

 haired in the apical part. 



Length. Fully 1 to 1,6 mm. 



A. halterata is not rare in Denmark; Copenhagen, Dyrehaven, 

 Holte, Ørholm, Hillerød and on Ærø (Th. Mortensen, the author); 

 the dates are ^Vs — ^Vio in 1917 to 1921. It may be taken on windows, 

 but also in woods. 



Geographical distribution: — Denmark, England and, according 

 to a specimen sent from Pater Schmitz, also Holland. 



Remarks: Wood divides the species into a larger, darker form 

 with brown halteres, and a smaller, generally paler form with yellow 

 halteres, and he declares the former to occur in woods, the latter in- 

 doors and in gardens; as said above I have taken my specimens both 

 indoors and in woods, and they have all yellow halteres. I think it 

 possible that Wood has mixed his species with the very similar 

 juscohalterata. 



