96 SYHPHIDiE. 



hairs behind vertex. In $ , head deep chrome-yellow, vertex 

 rather narrowly black, the colour carried very narrowly a little 

 way down eye-margins ; pubescence of frons much less dense on 

 upper part, that of face extremely fine, almost invisible. Thorax : 

 dorsum moderately shining black, with (especially in the $ ) a 

 deep blue reflection in certain lights ; in addition, centre of dorsum 

 from anterior to hind margin narrowly dusted with greenish-grey, 

 in which (in 2 ) traces of a pair of narrow median brownish stripes 

 can be seen in perfect specimens. Side margins broadly and 

 conspicuously orange-yellow from humeri to scutellum. Sides of 

 thorax black, with two squarish yellow spots immediately below 

 the humeri, thus forming three subequal spots in a vertical row; 

 a large, oblong spot, placed vertically, on niesopleui'a, connecting 

 the side marginal stripe of the dorsum with a horizontal one on 

 the sternopleura, which latter spot is contiguous with two others 

 (forming a slightly curved row of three), more or less oblong, the 

 last one lying just behind and below the wing-base; all the spots 

 very clear cut and bright orange-yellow. In $ they are consider- 

 ably fused, mainly through the large size of the mesopleural spot, 

 which extends to nearly all the others, so that the whole sides of 

 the thorax are practically unicolorous, leaving only the lower 

 surface of the thorax black. Pubescence of thorax brownish- 

 yellow on dorsum, bright yellow or orange-yellow towards sides, 

 paler yellow on pleurse ; some stiff black hairs on hind corners of 

 dorsum. Scutellum deep lemon-yellow, more or less translucent 

 and often with centre darkened ; pubescence wholly black, long 

 and copious. Pubescence of dorsum of thorax in $ blackish- 

 brown. Abdomen moderately shining black, with a pair of well 

 separated orange-yellow spots on 2nd segment, elongate, rather 

 curved, the inner ends rounded, the outer ends passing their full 

 width over side margins on anterior corners ; 3rd and 4th segments 

 with an unbroken yellow band on each, barely appreciably 

 emarginate in middle on both front and hind sides ; each spot lying 

 across centre of segment and passing its full width over side 

 margins ; the second one of the bands placed a trifle nearer the 

 front than the bind margin and very slightly widening on side 

 margins ; 5th segment mainly orange, but with a black triangle in 

 middle or hind margin in <S , and with hind margin all black in $ . 

 Pubescence of abdomen wholly black except at sides near the base, 

 where it is long, copious and yellow. Venter yellowish, blackish 

 towards tip. Genitalia in S dull orange witli long black 

 pubescence. Lecfs orange-yellow. Hind femora on apical half, 

 hind tibiae and all tarsi, black ; under side of hind metatarsus with 

 golden-yellow pubescence. Pubescence of legs mainly confined 

 to a little soft, pale yellow hair behind and below the anterior 

 femora and the basal half of hind pair ; black hairs on black parts 

 of hind legs. Wings pale yellowish-grey ; stigma brownish-yellow ; 

 halteres orange. 

 Length, 9-12 mm. 



