50 Syrphidae. 



the small frons yellow. Epistoma only keel-shaped below, not much 

 protruding, and with the central knob smaller and lower down than 

 in tibialis; the epistoma is yellow, thinly yellow-haired, the mouth 

 edge and the central knob black. Occiput black, grey pruinose, the 

 hairs yellow above, white below and on the black jowls. Antennæ 

 black, third joint more brownish, palest beneath at base; it is four 

 times or more as long as broad; arista brown, shorter than the third 

 joint, inserted about a quarter of the length from the base. Eyes with 

 short, whitish and brown hairs, arranged so that two, or about three 

 white bands run down the eyes. Thorax black or æneous, densely 

 and rather coarsely punctate and densely clothed with short, deep 

 yellow hairs, not longer on scutellum ; it has two short, approximated, 

 brownish stripes in front which are more or less distinct, sometimes 

 somewhat indistinct. Scutellum has the apical margin yellow or whitish 

 yellow. Pleura with somewhat long, yellowish white hairs. Abdomen 

 relatively broad and not long, with the first segment shorter than in 

 tibialis; it is densely and rather coarsely punctate, most coarsely on 

 the first segment, it is slightly shining except at the extreme hind 

 margins of the segments. Abdomen is black and red, the red colour 

 occupies the posterior part of the second segment, the third and the 

 anterior half of the fourth segment; on the second segment the black 

 colour is at the sides continued to the hind margin. Sometimes there 

 are a pair of black side spots on the third segment. Abdomen is 

 clothed with short hairs, only a little longer at the basal corners ; the 

 hairs are mainly yellow, but black on the disc towards the hind 

 margins ; the pale hairs form more or less distinct arcuated fasciæ on 

 the front part of the third and fourth segments. Venter translucent 

 at the base, reddish in the middle, but the apical part of the fourth 

 segment and all the transformed segments black; the venter is sparingly 

 clothed with pale hairs, most dense just at the base and towards the 

 apex; the fourth ventral segment somewhat punctate, slightly excised 

 in the hind margin at each side so that a slightly produced part is 

 formed in the middle. The transformed genital segments form a large 

 knob on the ventral side. Legs yellow, the basal part of the anterior 

 femora, and the hind femora to more or less near the apex black; 

 hind metatarsus darkened above, and the hind tibiæ often with a 

 dark patch or ring on the middle; hind metatarsus a little thickened. 

 The legs haired about as in tihialis with pale hairs. Wings hyaline 

 or very slightly tinged; stigma brownish. Squamulæ and balteres yel- 

 lowish white. 



Female. Frons black, punctate, rather narrow upwards and 

 together with the vertex much narrower than in tihialis ; on each side 



