Empididae. 253 



dorsocentral bristles backwards. There are some notopleural and a 

 postalar bristle, sometimes also a posthumeral bristle. Scutellum with 

 two long, marginal bristles. Metapleura with very short, scarceiy 

 observable hairs. Abdomen somewhat robust, consisting of eight seg- 

 ments; in the male it terminates with a small, knob-like forceps. In 

 the female the abdomen is pointed, terminating with two small styli- 

 form lamellæ. Legs somewhat robust, front and hind femora some- 

 what thickened, the middle femora less or not thickened; in some 

 species the hind tibiæ are tooth-like prolonged beyond the insertion 

 of the metatarsus. The legs are short-haired and with more or fewer, 

 generally only few bristles; the tibiæ may be with or without apical 

 spurs. The hind tibiæ have at the apex on the postero-ventral side 

 a small elevation which has a dense, short pubescence, and the same 

 pubescence is generally found on the posterior side of the metatarsus; 

 it is this elevation which is in some species prolonged as a tooth 

 beyond the insertion of the tarsus, as mentioned above. There are 

 two claws, two pulvilli and a very small empodium, terminating in 

 a bristle and with bristles on the lower side. The wings with a short 

 mediastinal vein, not reaching the margin ; the subcostal vein terminates 

 about in the middle of the costa; the cubital vein unforked and thus 

 one cubital cell; the discai vein likewise unforked and thus three 

 posterior cells; no discai cell; the lower branch of the postical vein 

 wanting, and no anal cell present; anal vein likewise absent or only 

 indicated; the second basal cell longer than the first. No stigma. 

 Axillary lobe somewhat well developed. Alula not developed, the 

 margin here fringed. Alar squamula small and narrow, fringed at the 

 margin. 



The developmental stages of Drapetis are not known. 



The species of this genus are rather easily known by their thick- 

 set shape and short, broad thorax. They occur especially on fieids 

 and commons in grass and low herbage, but do not seem to belong 

 to woods. The species, or some of them, seem to hibernate as imago, 

 thus I possess D. aterrima taken with the sieve on ^0/2 in flood refuse, 

 and Zetterstedt mentions D. flavipes {Tachydromia nigra) as taken 

 under stones in October. 



Of the genus 13 (14?) species are known from the palæarctic 

 region; 5 have hitherto been found in Denmark. 



Tahle of Species. 



1. The apex of the hind tibiæ prolonged tooth-like beyond the 



insertion of the metatarsus 1. aterrima. 



— The apex of the hind tibiæ not prolonged beyond the in- 

 sertion of the metatarsus 2. 



