242 Orthorrhapha brachycera. 



not longer than broad. Thorax not silvery, a little whitish grey 

 pruinose, especially at the humeri. Abdomen metallic green or æneous, 

 often with coppery reflexes; it is somewhat whitish pruinose, especi- 

 ally down tho sides, and there is (generally) no yellow spots. Front 

 coxæ more or less, often almost quite yellow; fetnora yellow, only 

 the hind femora as a rule with black apex; the femora mainly short- 

 haired. Squamular fringe brownish or yellow. 



Length 4,4 to almost 6 mm. 



A.argyria is less common in Denmark than the preceding species; 

 Frederiksberg Have, Ordrup Mose, Lyngby Mose, Hillerød, Faxe Lade- 

 plads; in Jutland at Thisted, and on Bornholm at Almindingen. My 

 dates are ^ii — ^'''s. It occurs in similar piaces as leucocephala and together 

 with this and the foUowing species. The female of argyria has appeared 

 rare to me, and it may perhaps have another habit than the others; 

 thus in Almindingen both argyria and argentina were present at a 

 stony streamlet in the wood; by working with the net above the 

 water and in the herbage at the border, I caught some males of 

 both species, but w^hile I caught about fifty females of argentina, I 

 got not a single of argyria, and nevertheless I do not doubt the correct- 

 ness of my Identification. — All the females of argyria I have examined 

 have the apex of the hind femora more or less black or blackish^ 

 and no yellow spots on abdomen, only the venter may be a little 

 translucent at the base; but I have only had few females. 



Geographical distribution : — Europe down into Spain and Italy,^ 

 and further on the Canary Islands; towards the north to southern 

 Sweden. 



6. A. argentina Meig. 



1824. Meig. Syst. Beschr. IV, 47, 3, et 1830. VI, 362 (Porphyrops), 

 et 1838. VII, 154,3. — 1843. Zett. Dipt. Scand. II, 591, 79 (Dolichopus). 

 — 1862. Schin. F. A. 1, 191. — 1878. Kow. Verhandl. zool. bot. Gesell. 

 Wien, XXVIII, 450,8. — 1903. Kat. palåarkt. Dipt. II, 323. — Dolichopus 

 diaphanus 1823. Fall. Dipt. Suec. Dol. 16, 17, p. p. J*. — 1838. Zett. Ins. 

 Lapp. 712, 17, p.p. 



Male. Vertex and frons silvery white; eyes with yellowish or pale 

 brownish hairs. Epistoma narrow, silvery white. Palpi small, black. 

 Occiput grey pruinose; postocular bristles black above, whitish below. 

 Antennæ black, distinctly longer than the head, third joint fully as 

 long as the two basal joints; arista short, shorter than the antennæ. 

 Thorax metallic green, silvery pruinose, especially when seen from in 

 front; the part in front of the scutellum not pruinose; acrostichal 

 bristles long; scutellum not hairy. Pleura greenish, grey or whitish 



