366 Syrphidae. 



femora and tibiæ may be a little brownish or have faint brownish 

 rings, and also anterior femora may be a little brownish; the hairs 

 are inconspicuous and all pale, only middle femora with a row of 

 longer hairs below. Wings slightly yellowish or brownish tinged; 



f'ig. 133. Wing of B. elongata $. 



stigma brown, or paler and then slightly marked; the cross- veins as a 

 rule a little infuscated and likewise the apex of the wing above the 

 discai vein. Squamulæ and fringes whitish or pale yellow. Halteres 

 yellowish white, the knob often with the apical part darkened. 



Female. Vertex somewhat narrow, black, shining; frons grey 

 pruinose but from the vertex a narrow, black line stretches down- 

 wards, it ends, however, about one third before the antennæ so that 

 the space above the antennæ is quite pruinose; the pubescence white. 

 The mouth edge more yellow than in the male, also the front edge 

 yellow. Antennæ yellow or with only the margin of third joint dark. 

 The hairs on thorax shorter; scutellum generally blue. Pleura more 

 pruinose than in the male and with more pubescence, only the lower 

 corner of mesopleura polished; the greater part of meso- and ptero- 

 pleura yellowish. Abdomen coloured mainly as in the male, the spots 

 on fifth segment seem always to be present. 



Length 7 — 10,5 mm. 



As seen this species may vary somewhat, among others with 

 regard to the abdominal markings; this is the reason for the many 

 species distinguished by Meigen, and also the faet that he has treated 

 males and females as separate species. 



B. elongata is common in Denmark; Ordrup Mose, Ermelund, 

 Dyrehaven, Lyngby Mose, Egebæks Vang, Tisvilde; on Lolland at 

 Strandby; on Langeland at Lohals, and in Jutland in Vejle Nørreskov, 

 Grejsdal and Højenbæk Dal at Vejle, at Horsens and at Jerup near 

 Frederikshavn. My dates are ^/e— ^/g; it is most common in late 

 summer and autumn. It occurs in woods and thickets, generally 

 hovering on shaded and somewhat humid piaces. 



Geographical distribution:— Europe down into Spain and Italy : 

 towards the north to northern Sweden. and in Finland. 



