Empididae. 43 



closing cross-veins perpendicular lo, not parallel with the margin; atthe 

 hind-margin, on each side of the lovver corner of the discai cell (in 

 the third and fifth posterior cell) there is a more or less faint, greyish 

 patch, sometimes very slightly visible. 

 Length 4.3 — 5 mm. 



'U.^ 



Fig. S.. Wing of Hh. sjnssirostris Q. 



This species cannot be confused with nigripes; besides the 

 size, the design of thorax and the clear wings, it is distinguished in 

 the male by the thickened front metatarsi and the curiously haired 

 middle metatarsi, as well as by many other differences in the pilosity 

 of the legs, and in the female by the shape of the discai cell, 



Rh. spissirostris seems not to be common here; it occurs near 

 water; Amager Fælled, Hillerød, Boserup near Roskilde and on Falster 

 at Resle. It is a spring species, my dates are '^'^/■^ — ^^Ig; on the latter 

 date I took it on Amager Fælled flying lovv over a water pool to- 

 gether with the following species. Zetterstedt notes (VIII, 3031) as 

 communicated by Stæger „Occurrit . . . tantum in litore maris", but 

 this is not correct as the localities Hillerød and Boserup show. 



Geographical distribution : — Northern and middle Europe ; its 

 southern limit lies in Austria; towards the north to middle Sweden, 

 and in Finland. 



4. Rh. dissimilis Zett. 



1849. Zett. Dipt. Scand. VIII, 3031, 2—3. — 1903. Kat. palåarkt. 

 Dipt. II, 224. 



This species is very similar to spissirostris, and I shall therefore 

 only describe it comparatively. 



Male. Somewhat larger than spissirostris; frons somewhat broader. 

 Thorax much darker grey and shining, the two stripes hence much 

 less distinct, especially outwards as the sides of the disc are rather 

 dark; the stripes are broader than in spissirostris. The dorsocentral 

 and acrostichal bristles slightly longer; all thoracic bristles black; on and 

 behind the humeri there are fme, yellow hairs as in spissirostris. 

 Abdomen and exterior genitalia quite as in spissirostris, the fan-like 

 hairs at the hind margin of the segments stronger. Legs as in spissi- 



