238 SIRPHIDiE. 



183. Xylota bistriata, Bnm. (PI. V, fig. 13.) 



Xylota bistriata, Brauetti, Rec. Ind. Mus. xi, p, 235 (1915). 



S ? • Head : eyes in S practically contiguous for about lower 

 third of distance from vertex to base of frons. Width of vertex 

 about one-eighth tliat of head, vertex blackish-seneous with a 

 little pale hair, tlie siwall ocelli distinct, reddish. Eyes in $ 

 separated by a frons about one-eighth the breadth of the head, 

 widening a little at base of antennae. Face and frons blackish, 

 covered with yellowish-white tomentum ; antennae covered with 

 3'ellowish-grey dust ; arista black, base brownish-yellow. Occiput 

 blackish-grey, with whitish dust ; some bright yellow short hairs 

 along top of head, intermixed behind vertex with black ones. 

 Ocular orbit with a fringe of short white hairs which are longest 

 on under side of head. Thorax : dorsum greenish-aeneous, with 

 short and rather thick bright yellow pubescence. A pair of well- 

 separated pale median longitudinal stripes bearing short bright 

 yellow hairs, becoming indistinct behind but just attaining the 

 scutellum, which latter is also greenish-aeneous with short yellow 

 pubescence and a fringe of short yellow hairs below hind margin. 

 Sides of thorax blackish-aeneous, nearly bare; sternopleura and 

 mesopleura with agre}' tinge and bearing some short j'ellow pubes- 

 cence. Humeri apparently bare ; but if viewed from behind they 

 are seen to bear some short yellowpubescence. Abdomen: blackish- 

 aeneous with a dull steel tinge, whicli on the 2nd segment in the $ 

 may occasionally show, seen from behind, a pale violet reflection ; 

 basal segment a little darker; on hind margin of both 2nd and 

 3rd segments a large dull black (seen from behind) subtriangular 

 spot, its apex reaching nearly to the base on the 2nd segment, 

 but only to the middle on the 3rd segment. Dorsum of abdomen 

 with microscopic dark hairs, sides with short pubescence, which 

 is longer towards the base and is yellowish in the J and white 

 in the $ . Genitalia in r^ globular, of a dull steel colour, with 

 some yellow hairs ; ovipositor brownish-yellow. Legs : coxae 

 aeneous, grej^-dusted ; hind pair with soft pale hair below. 

 Anterior legs yellowish with short concolorous pubescence, which 

 is longest on inner side of middle tibia> ; tips of middle femora 

 narrowly brown. Anterior tibiae longitudinally streaked irregu- 

 larly with brown on inner and outer sides, last tarsal joint brown. 

 Hind femora considerably incrassate, brownish-yellow with a 

 broad blackish -brown median band, sometimes incomplete on 

 inner or under side, and the tips dark brown ; hind trochanters 

 with a moderately long distinct black spine ; hind femora with 

 an outer row of 6 to 8 black spines of moderate size on under 

 side, gradually diminishing in length distally, and also at the tip 

 an inner row of about four shorter ones of uniform length ; with a 

 little long soft pale yellow hair on middle of under side ; remainder 

 of hind femora with very short yellow pubescence, which is 

 longest about the middle on the outer side. Hind tibiae 



