Syrphus. 327 



into Bohemia, and also recorded from Italy; towards the north 

 to northern Sweden, and in Finland; it seems upon the whole to 

 be rare. 



27. S. triangulifer Zett. 



1843. Zett. Dipt. Scand. Il, 737, 39 (Scaeva). — 1862. Schin. F. A. 1, 

 308. — 1901. Verr. Brit. Fl. VIII, 402, 27. — 1907. Kat. palåarkt. Dipt. 

 111, 71. 



Male. Vertex triangular, slightly elongate; frons and epistoma 

 not broad, frons somewhat arched, black, below narrowly yellowish 

 just above the antennæ ; epistoma yellow, a little greyish white pruinose, 

 the mouth edge and lower side parts blackish. Jowls small, blackish, 

 grey pruinose. Vertex and frons black-haired ; epistoma with mainly 

 black hairs but yellow-haired below. Occiput vvhitish grey pruinose, 

 the hairs white below, yellow upwards; above a short row of over- 

 hanging hairs. Eyes bare. Antennæ short, yellowish, third joint short 

 oval, more or less darkened above; arista about as long as the 

 antennæ. Thorax æneous, shining, clothed with yellow hairs. Scutellum 

 yellow, blackish just at the basal corners, with yellow hairs, slightly 

 longer than on thorax. Pleura with longish, yellow hairs. Abdomen 

 narrow, narrower than thorax, duU black, a little shining at base and 

 apex; there are three pairs of not large, yellow spots; the basal spots 

 are quite small, roundish or a little triangular; they lie about on the 

 middle, near the side margin but not reaching it; the spots of the 

 second pair lie at the front margin, they are triangular, the front 

 margin straight, at the sides they occupy half the length of the seg- 

 ment and from here the hind margin slopes forwards, meeting the 

 front margin in a somewhat rounded inner corner, and leaving about 

 the fourth of the breadth black; the third pair are quite similar; the 

 spots go in full width over the margin; the fifth segment has very 

 indistinct, pale basal corners, The hairs on abdomen follow mainly 

 the ground colour, but are pale at the base; at the sides they are 

 somewhat long and all yellow. Venter, as far as I could see, dark 

 yellowish or greyish yellow, with long, pale hairs (it has perhaps dark 

 bands). Genitalia relatively large, black and shining, with black hairs. 

 Legs not robust ; they are yellowish, anterior femora blackish on about 

 the basal third, hind femora black with the extreme base and the 

 apex yellow ; middle tibiæ with faint traces of a dark ring in the 

 middle, hind tibiæ with a distinct, blackish middle ring and hind tarsi 

 brownish or blackish; hind metatarsi very slightly thickened or almost 

 not. The long hairs on femora yellow; the short hairs all yellow 

 except at the apex of hind femora on the anterior side and just 



