442 Syrphidae. 



Male. Vertex somewhat large, black, dullish; frons black, shining 

 anterioriy, a little pruinose posteriorly and greyish white or yellowish 

 pruinose at the eye-margins ; it is somewhat broad, the upper angle 

 rectangular and the eyes touching for a short distance; epistoma 

 somewhat broad, only slightly widening downwards, greyish white or 

 sometimes pale yellowish pruinose, the middle stripe, the mouth edge 

 and the lower lateral parts black, shining; jowls black, somewhat 

 greyish pruinose. Vertex with black, posteriorly yellow hairs, frons 

 yellow-haired ; sometimes vertex and frons quite black-haired; epistoma 

 with long, whitish or pale yellow hairs; the epistoma is somewhat 

 hollowed below the antennæ, somewhat retreating below the central 

 knob and rather descending. Occiput white pruinose along the eye- 

 margin to above the middle, for the rest blackish^ somewhat greyish 

 pruinose; the hairs whitish below, yellow above with more or fewer, 

 sometimes rather many black hairs at the eye-margin. Eyes with 

 brown or black hairs, densest down the middle. Antennæ black, 

 third joint short, almost higher than long; arista black or brownish, 

 plumose on the basal half. Thorax black or brownish black, a little 

 shining behind, distinctly greyish or yellowish pruinose on the front 

 half with two faint, dark middle stripes and on each side a roundish 

 spot; the pruinose stripes on each side of the middle stripes are pro- 

 longed a little backwards in on the black part; thorax is clothed 

 with darker or paler yellow, sometimes almost whitish hairs, and 

 sometimes there is a cross-band of black hairs just behind the middle. 

 Scutellum yelloAvish brown or brown, with yellow^ or paler hairs. 

 Pleura with long, pale yellow hairs. Abdomen somewhat narrow and 

 a little conical, it is black, dull, third and fourth segments with a 

 shining, transverse middle band and broad dull front and hind margins, 

 generally less distinct on fourth segment; the second segment has two 

 small, transversely triangular, yellowish side spots, lying on the front 

 part of the segment; the spots are shining; the second segment has a 

 yellow hind margin, on third and fourth segments this margin is very 

 narrow and obscure or wanting. Abdomen is mainly black-haired but 

 the hairs are pale at the base and on the basal half of the second 

 segment, on the front margin of third and slightly on fourth segment, 

 and on the genitalia; the hairs are also pale at the sides. Venter 

 greyish black with pale incisures and long, pale hairs, second segment 

 pale with a dark middle spot. Legs with the femora somewhat varying 

 in colour, either quite black with only just the apex yellow, but gener- 

 ally the hind femora a little reddish at the base, or they may be 

 more pale, and sometimes the basal half is yellow and the base of 

 the anterior femora more or less pale; the front and hind tibiæ have 



