usia. 283 



comparatively bare, but the sides of the abdomen with pale yellow 

 hairs. Genitalia small, inconspicuous, conical, blackish. Venter 

 blackish, posterior margins of segments whitish grey. Legs 

 uniformly black, very shortly pubescent; femora with some soft 

 hairs ; hind tibiae with short bristles. Wings nearly clear ; sub- 

 costal cell pale yellow ; venation normal ; halteres dark brown or 

 blackish, knobs large. 



5 . Head: eyes separated by a wide frnns equalling one-third 

 width of head ; upper half of frons, as also whole back of head, 

 greyish yellow, the latter with black hairs as in <S ; upper half of 

 Irons with a row of hairs near margin of eyes; vertical tn angle 

 distinct, dark , two narrow fuscous vertical lines from the vertical 

 triangle to an irregular transverse dark streak dividing the upper 

 from the lower half of the frons, the latter part being more ash- 

 grey and unmarked ; lower part of the head greyish ; proboscis and 

 mouth larger than in cf ,thus narrowing the cheeks considerably. 

 Thorax yellowish grey, with a median pair of narrow fuscous 

 lines, with a broader outer stripe, more or less divided into three 

 spots, the anterior one small and conical, the other two more 

 elongate ; also an indistinct central line between the median pair 

 of narrow ones, and a small spot above the insertion of the wings : 

 sides of thorax cinereous grey ; scutellum yellowish grey, with 

 some yellow hairs as in J .. Abdomen black, bare ; posterior 

 margin of segments rather broadly yellow ; sides with a little less 

 hair than in J ; venter blackish ; ovipositor pale yellow, in- 

 conspicuous. Legs and ivings as in S . 



Length, 2-J- 3| mm. 



Described from several of both sexes taken by Dr. Annandale 

 at Simla, 16. v. 1909, where it was common on Sedum rosulatum 

 (white stonecrop); the species was not seen anywhere except on 

 this plant. Phagu, 18-21. v. 1916 {Annandale). 



Types in the Indian Museum. 



226. Usia marginata, Brun. 



Usia marginata, Brimetti, Rec. Ind. Mus. iii, p. 228 (1909). 



S . Bead with eyes contiguous for a shorter space than in 

 sedophila, black, hare ; upper facets larger than lower, and more 

 sharply defined from one another than in sedophila ; frons ash- 

 grey, small, with a few black hairs ; vertex prominent, with some 

 black hairs, ocelli distinct : front margins of eyes and cheeks 

 with long black hair, which is considerably thicker on the under- 

 side, and which extends over the whole of the back of the head. 

 Antennas as iu sedophila, but the third joint with a pale ring at 

 the base, giving the appearance of a minute basal joint, and the 

 tip bears on its upper side a minute style-like process, just beyond 

 the subapical depression ; 1st joint with some bristly black hairs, 

 2nd with one or two minute hairs, 3rd bare. Thorax dull 

 black, almost velvety, covered lightly on dorsum, and more thickly 



