Empididae. 63 



also the coxæ which are only veiy slightly pruinose. The front 

 femora have short, fine hairs below; the middle femora have antero- 

 and postero-ventral rows of short, sUghtly stronger hairs; the hind 

 femora are somewhat long and a Httle thickened towards the apex, 

 they have short hairs above and two ventral rows of short, some- 

 what strong, bristly hairs, the antero-ventral row is very dense at the 

 apex; on the postero-ventral side near the apex there is a dense and 

 compact tuft of strong hairs, placed on a sHght swelling, and at the 

 apex below there is an obliquely placed tuft of scaly hairs, this tuft 

 is compressed having the hairs placed in one row; these two black 

 hair-tufts are very conspicuous on the yellow legs; the front tibiæ 

 are short-haired, only with a small subapical bristle; middle tibiæ 

 wlth a little longer hairs ventrally, but likewise only with small 

 bristles at the apex; the hind tibiæ strongly curved and somewhat 

 excised at the base, with dense hairs on the ventral side which form 

 a small tuft placed on a somewhat thickened part just after the ex- 

 cision; on the dorsal side there are short hairs and some fine bristles; 

 the front tarsi have some curious, long and delicate, erect hairs on 

 the ventral side; the posterior tarsi are short-haired, somewhat densely 

 below; the posterior femora have a very dense, short, white pubes- 

 cence below. The hairs and bristles are black or blackish brown. 

 Besides the legs have the ordinary clothing of short hairs, somewhat 

 conspicuous on account of the yellow colour of the legs. Wings 

 slightly yellowish tinged; veins light brownish, anal vein distinct, 

 reaching the margin. Stigma faint, yellowish. Halteres yellow or 

 yellowish white. 



Female. Frons broad, grey, with an impressed middle-line. Ab- 

 dornen short haired. Front legs short haired, tarsi without long hairs; 

 posterior legs compressed, middle femora short ciliated above, pen- 

 nate below, middle tibiæ pennate on both sides with very long and 

 rather broad scaly hairs; hind femora and tibiæ pennate on both 

 sides, the scaly hairs on the dorsal side of the femora short and not 

 very broad, the rest long and broad as on the middle tibiæ; the 

 scaly hairs are blackish or dark brown, when seen towards the light 

 they are brownish. Wings brownish fumigated. 



Length 4,5 to about 6 mm. 



This species is at once recognised by the colour, the shape of the 

 legs and exterior genitalia in the male, and the very strongly pennate 

 legs in the female. 



Rh.pennata is not common in Denmark and has only been taken 

 at few localities, but sometimes present in no small number; Ler- 

 søen, Dyrehaven; on Lolland at Maribo and in Jutland at Silkeborg; 



