322 Syrphidae. 



more or less obvious, black side spots just at the margins of the seg- 

 ments; is has long, pale hairs, on the apical half also short, black 

 hairs. Genitalia relatively large, varying in colour from almost quite 

 black to quite reddish; the hairs black and pale. Legs varying in 

 colour, in pale specimens quite yellow with only hind femora and 

 tibiæ a little darkened in the middle and hind tarsi brown ; in dark 

 specimens the anterior femora have the basal part black, hind femora 

 black w^ith apex and often also base yellow^, hind tibiæ with a black 

 ring in the middle and hind tarsi black. The long hairs on femora 

 are yellow, the short hairs black on anterior side of hind femora in 

 the apical half and all round at apex, and on the dorsal and anterior 

 side of hind tibiæ, for the rest yellow; hind tibiæ with an antero- 

 dorsal fringe with some long hairs about the middle. Wings hyaline 

 to rather brownish tinged. Squamulæ yellowish with yellow margin 

 and fringes. Balteres yellow. 



Female. Vertex narrow, shining black on a quadrate space ; frons 

 yellow dusted, with a black, shining middle stripe from the vertex to 

 the bare and shining, yellow space above the antennæ, the stripe a 

 little widened below; the hairs dark about the vertical triangle, yellow 

 downwards. Abdomen as in the male, but the basal spots sometimes 

 going near to each other in the middle and the bands narrower, not 

 emarginate; the third band on the hind margin of fourth and front 

 margin of fifth segment emarginate behind as the fifth segment has 

 two yellow basal corner spots. Legs as in the palest forms of the 

 male, sometimes all yellow. 



Length. This species varies much in size, the length from 7 to 

 about 10 mm. 



The pupa is recorded by Zetterstedt (1. c. 741) and described as 

 "pisiformis, inermis, albida". 



As seen this species varies somewhat with regard to the colour of the 

 frons and its pubescence in the male and the colour of the legs; the 

 darker varieties answer to placidiis of Meigen. It also varies much 

 in size as seen from the given lengths, and at the same time the ab- 

 domen varies in breadth, the larger specimens being stronger and with 

 the abdomen considerably broader. The species will generally be 

 known from cinctellus by the yellow-haired scutellum, but otherwise 

 the narrower frons and epistoma, the not elongated central knob, the 

 shorter third antennal joint and shorter, bare arista and the shorter 

 abdomen with the single segments generally relatively shorter will 

 distinguish it. 



S. cinctus is not rare in Denmark; at Copenhagen, Ordrup Mose, 

 Charlottenlund, Ermelund, Dyrehaven, Bagsvær, Hareskov, Geel Skov, 



