156 Syrphidae. 



brown or blackish above and at apex; arista apparently bare. Thorax 

 black, pruinose and almost dull, with indistinct traces of duller strlpes; 

 it is clothed with long, erect, greyish yellow hairs, only at the margins 

 Mith some few dark hairs and some on scutellum; there are postalar 

 and scutellar marginal bristles, but they are weak and slightly con- 

 spicuous, and I could se no notopleural bristles. Pleura with white 

 hairs, above and in front black hairs. Abdomen black, almost quite 

 dull, with long, erect, whitish hairs, only at the hind margin of third 

 segment and at the apex some black hairs. Venter somewhat greyish 

 pruinose, with pale hairs. Legs black, anterior femora yellowish at 

 the extreme apex; tibiæ yellow on the basal part, anterior tibiæ also 

 slightly yellow at apex. The legs almost quite white-haired, only the 

 hairs behind the front femora and at the apex of middle femora black, 

 and the hind tibiæ with a short, dark fringe on the antero-dorsal side, 

 longest on the middle; the hairs on femora long and rather dense: 

 hind femora a little black-setulose beneath except at the base; hind 

 metatarsi not thickened. Wings a little tinged; the upper angle at 

 the upper marginal cross-vein acute. Squamulæ whitish with a whitish 

 fringe. Balteres brown with the knob blackish. 



Female. Frons rather broad, distinctly trisulcate, yellow-haired ; 

 on vertex some black hairs. Epistoma much more hol^owed below 

 the antennæ and with the central knob and lower part more pro- 

 minent than in the male; it is only pruinose below the antennæ, for 

 the rest shining. Antennæ with the third joint a little larger than in 

 the male, similarly coloured. Thorax shining, fmely punctate, with 

 short, somewhat erect, yellowish white hairs. Abdomen likewise shining, 

 with short, depressed, white hairs, a little longer and more erect at 

 the sides and at the basal corners of the segments. Legs with the 

 apex of anterior tibiæ distinctly pale; hind femora not setulose beneath. 

 Balteres orange. 



Length 6,5 to fuUy 7 mm. 



Remarks: This species seems to vary with regard to the colour 

 of the thoracai hairs; Loew describes thorax as mainly black-haired; 

 the above description of the male is made from a specimen from 

 Zermatt, kindly sent to me from Mr. Th. Becker; it has thorax almost 

 quite pale-haired. — The species bears some resemblance to C. barbata, 

 but this is a larger species with the arista distinctly pubescent, the 

 frons in the male not large and swollen, epistoma narrower and thorax 

 shining; in the female it has likewise a much narrower frons and the 

 thoracai hairs more depressed. The nearest ally to frontalts is melanopa 

 Zett. but it is a larger and blacker species, as the antennæ and legs 

 are black. 



