Eristalis. 441 



below more or less to quite black on the apical part. Wings yellow 

 or brown at the base, for the rest hyaUne or slightly yellowish tinged ; 

 below the stigma a brown blotch, going down over the base of the 

 cubital vein and the basal vein of the discai cell, and it goes more 

 or less distinctly to the medial cross-vein, but it is sometimes nar- 

 rower and not reaching this vein. Stigma twice as long as broad, 

 blackish. Squamulæ and fringes brownish. Halteres yellow. 



Female. Vertex and frons broad, a little widening downwards, 

 all black and shining down to the antennæ, or very slightly duliish 

 across the middle, the frons only a little whitish pruinose to each 

 side above the antennæ ; the hairs are black on the vertical half, dark 

 yellow on the frontal half, sometimes the black hairs more restricted; 

 epistoma a little more densely pruinose than in the male. Abdomen 

 with generally small spots at the basal corners of second segment, 

 often obscured and not rarely quite wanting; the pale hind margins 

 generally very narrow, often obscure or wanting; abdomen is all 

 shining without dull margins to the segments; the hairs are black 

 except on the basal part of second segment and on the fifth segment. 

 Hind femora generally pale on the basal part, front tarsi often pale 

 at the base, and hind tarsi paler yellow on the base than in the male; 

 the legs quite or mainly pale-haired. The wing-blotch larger and more 

 distinct than in the male, always broad and reaching the medial cross-vein. 



Length 9 — 12 mm. 



This species is, as remarked above, nearly related to vitripennis 

 but distinguished with certainty by the characters given under that 

 species; as correctly remarked by Zetterstedt the slender legs, especially 

 in the male, are characteristic for rupium, and likewise the all shining 

 abdomen of the female without dull margins on the segments. 



E. rupium is not common in Denmark; Ordrup Mose, Dyrehaven, 

 Tyvekrog; in Jutland in Grejsdal and Højenbæk Dal at Vejle, at 

 Horsens, Silkeborg and Laurberg south of Randers. My dates are 

 22/g — i3/^o_ j jjave taken it on various Gompositæ and Umbelliferæ; 

 the male seems to be much rarer than the female, as also remarked 

 by Zetterstedt, only five males are found in our old collection and I 

 have myself never taken the male. 



Geographical distribution : — Europe down into Italy, and also 

 recorded from the Ganaries; towards the north to northern Sweden, 

 and in Finland, 



15. E. alpinus Panz. 



1798. Panz. Fn. Germ. LIX, 14 (Syrphus). — 1822. Meig. Syst. Beschr. 

 III, 398, 20 — 1862. Schin. F. A. I, 336. — 1907. Kat. palåarkt. Dipt. 

 III, 102. 



