Aphiochaeta. 407 



approximate. Antennæ of ordinary size or smallish, blackish brown 

 or dark brown; arista distinctly, but short-pubescent. Palpi diisky 

 yellowish, somewhat small, with ordinary bristles. Thorax black, 

 slightly shining, with brownish pubescence. Mesopleura bare. Abdomen 

 black, dull, with a little paler hind margins to the segments, sixth 

 segment a little elongated; very short hairs almost only to detect 

 at the hind margins of the segments, a little longer on sixth segment. 

 Hypopygium somewhat large, as long as the sixth segment, brownish; 

 it has numerous short hairs below^ on the sides and dense at the hind 

 corners; ventral plate a long, narrow process; anal tube quite small, 

 yellowish. Legs brown, front legs a little paler; hind femora a little 

 broad, the hairs below not long; hind tibiæ distinctly thickened in the 

 apical half, and here on the ventral side with about four erect bristles, 

 forming a short row; the posterodorsal bristles numerous, very small 

 and hair-like. Wings clear or nearly so, veins brown, the thin veins 

 fme; costa about 0,43 of the wing-length, costal divisions about as 

 4 — 2 — 1 ; angle at fork not small; costal ciha long; fourth vein distinctly 

 curved in its first part, for the rest nearly straight. Halteres black 

 or dark brown. 



Female. Similar to the male, likewise with the apical half of 

 hind tibiæ thickened, but wdthout erect bristles; the palpi paler. 



Length. About 1,3 mm. 



The female was hitherto not known, as seen above it will be 

 distinguished from its allies by the distinctly thickened hind tibiæ. 



A. erecta is rare in Denmark; on Langeland at Lohals ^7? 1920 

 and in Jutland at Hejls south of Kolding ^/t 1919 and in Egense Skov 

 at the east end of Limfjorden ^|^ 1921 (the author); in all two males 

 and tliree females. At Hejls I took two males and one female in 

 Company, and if I remember correctly they were taken on an umbel- 

 lifer. 



Geographical distribution: — Hitherto known only from Den- 

 mark and England. 



144. A. tibiella Lundbk. 

 1920. Lundbk. Vidensk. Meddel, fra Dansk naturh. Foren. 71, 24, 28. 



Male. Frons somewhat broader than high, black, slightly greyish 

 and a little shining; inner bristle of lower row a little below the outer 

 and equally distant from it and from the upper supraantennal ; supra- 

 antennal bristles unequal, the lower somewhat smaller than the upper; 



