Nov., 1911.] 
Life-Histories of Syrphidae II. 
40 r 
Adult. 
Genus Paragus Latreille. 
Description slightly modified, from Williston. Bull. U. S. Nat. 
Mus., No. 31, 89, (1886), p. 17. Small nearly bare species, 
abdomen curved downward at the tip black or greenish black 
with yellow on the face and reddish on the abdomen. Head 
broader than thorax; antennae about as long as the head, first and 
second joints short third longer than first two together; arista 
before the middle bare. Face convex with an obtuse tubercle. 
Eyes pilose, narrowly contiguous and often with an area of 
enlarged facets on the upper anterior part in the male. Abdomen 
as wide as thorax and twice as long of nearly equal width through- 
out, a shallow transverse depression on each segment, the distal 
end bent downward. Hind metatarsi much thickened as long as 
the remaining joints together. Marginal cell of wing open, third 
longitudinal vein straight, anterior cross-vein near the base of 
discal cell, the last section of fourth vein sinuate, terminating in a 
right angle on the third vein at a considerable distance before the 
tip. 
Paragus bicolor (Fabricius). 
c? 9 Length 5-6 mm. Eyes pubescent, the pile mostly grouped 
in two vertical stripes separated by a distinct vertical glabrous stripe 
(Figs. 29, 30). Face in the female white pilose with a shining 
black stripe reaching from antennae to the oral margin, narrower 
below; in the male wholly pure light sulphury yellow with yellow 
pile. Oval margin and cheeks shining black. Antennae black 
with some whitish pollen, the under side of the third joint reddish. 
Front of female narrowed above, not more than half as wide at the 
vertex as at the base of the antennae (Fig. 30); shining black 
narrowly dusted with whitish on the sides below, the latter not 
quite reaching the light color on the sides of the face; frontal 
triangle sulphur yellow, the eyes touching midway, and for about 
one-fifth the distance, between the anterior ocellus and the base 
of the antennae; “vertical triangle black light pollinose in front. 
Thorax black, a little shining with yellowish pile, in front with two 
whitish pollinose stripes. Pleurae silvery white pilose. Scutellum 
with a whitish border not extending to the anterior angles. 
Abdomen chiefly red, but variable in color; first segment black; 
second segment, often wholly black sometimes more or less red 
behind, sometimes only black on the sides. The black usually 
extends narrowly along the sides of the third segment, sometimes 
of the fourth and fifth also ; rarely, the third segment has a blackish 
band. Pile on the sides of the segments in front and on the lateral 
margins, and on the fifth segment, white, elsewhere obscure. 
Legs variable, frequently the basal portion of the front and mid- 
dle femora and the hind femora except the tip are black, elsewhere 
yellowish. Wings, nearly hyaline; stigma, dilutely yellowish. ,r 
