220 Records oj the Indian Museum. [VoL.xis 
widening of the 3rd segment more sudden than in the type and 
the Cherrapunji specimen. in both of which the greatest width of 
the abdomen is proportionately less, and the widening more gra- 
dual. However, I include all under one species as in every other 
particular they agree with one another and it is no uncommon 
thing for the yellow parts of a species of Syrphidae to be replaced 
in individuals by brownish. 
Baccha elegans, mihi, sp. nov. 
@ North Bengal; Lower Burma. Long. II—I2 mm. 
Head.—Eyes absolutely contiguous for about half the distance 
from frontal triangle to vertex; (in one example they are quite 
distinctly though very narrowly separated). Frons shining violet 
black, frontal triangle and face wholly deep chrome yellow, with a 
very distinct median black stripe, broader on upper part, from 
below antennae to mouth border. No obvious bump on face. 
Antennae wholly bright orange yellow, antennal prominence hardly 
noticeable. Occiput whitish grey, cut away in profile behind 
upper part of eyes; a fringe of short white hairs round entire 
ocular orbit. Proboscis brownish yellow. 
Thorax.—Dorsum shining deep blue, with very short whitish 
depressed pubescence. Sides dark blue black. Pale callus-like yel- 
low spots are placed as follows: a large one on the shoulder con- 
tiguous to a lateral oblong one along the side, just below the dor- 
sum and just touching a large perpendicular oblong one on the 
mesopleura, which in its turn is sub-contiguous to a round one on 
the sternopleura. A more or less oval one behind the wings. 
Scutellum mainly blackish brown, with a well marked pale lemon 
yellow base, this colour extending over the sides. Metanotum dark 
bluish black. 
Abdomen.—First segment very short, sub-triangular; 2nd 
exceedingly narrow and elongate; 3rd equally narrow on basal 
third, thence suddenly widening to three times that width, the 
whole segment less long than 2nd; 4th distinctly shorter than 
3rd, 5th less than half as long as 4th. The enlargement of the 
abdomen continues to the tip of the 4th segment, the 5th narrow- 
ing. ‘The 1st segment is wholly brownish yellow, the rest of the 
abdomen is shining dark brown, with a vague violet tint, and 
there is a pale narrow space at the junction of the 2nd and 3rd 
segments, also broadly at tip of 3rd segment. Genitalia shining 
brownish yellow, with some obscure markings and a small process 
below. Belly mainly a replica of upper side. The whole abdo- 
men with a little very short blackish pubescence, some longer, 
though still short, whitish pubescence at sides of first two segments. 
Legs.—Anterior pairs bright brownish yellow, bare except for 
a little pale hair below the femora; hind legs with coxae obscure 
above, femora darker brownish yellow, tibiae pale yellow on basal 
half, black on remainder, as is also the metanotum ; hind tarsi tips 
brownish. 
