SOME FLIES OF THE FAMILY ASILIDAE (DIPTERA) 
By Frank M. Hull 
University of Mississippi 
In this paper are descriptions of several species and 
genera of robber-flies. 
Zabrops new genus 
Type of genus: Triclis tagax Williston, 1884. Other Ameri- 
can flies put in Triclis Loew probably belong here. 
Small flies with short, appressed pile and comparatively 
robust form. From Triclis Loew they differ in the gibbous 
and prominent face, with numerous bristles below and 
little or no hairs in the upper part. Third antennal seg- 
ment swollen. Female terminalia generally similar to 
others in the Laphystini. Length 11 mm. 
Head : The face is prominent, short beneath the antenna 
but rising below into a gently rounded eminence, occupy- 
ing at least three-fourths of the face. The occiput is 
prominent below due to the gradual anterior recession of 
the eye ; its pile is dense and fine with 4 or 5 weak bristles 
on upper occiput. Proboscis short, robust, stout at base 
and not protruding beyond the face. Palpus minute, com- 
posed of 2 short segments. Antenna nearly as long as 
head; third segment swollen shortly beyond its base, and 
with style included, is about as long as first 2 segments 
combined. At its apex it bears a short, stout, spoon- 
shaped microsegment with enclosed spine. Thorax : The 
mesonotal pile is abundant, more or less appressed and 
undifferentiated. The lateral bristles are weak and consist 
of 2 notopleural, 3 or 4 supraalar, 2 or 3 postalar, and 
4 to 6 pairs on the scutellum. Prosternum not or only 
slightly dissociated ventrolaterally. Legs : The legs are 
stout, the hind femur a little swollen distally and all legs 
with dense, appressed, setate pile. The hind femur bears 
4 dorsolateral bristles, 2 lateral bristles and 3 dorsomedial 
bristles, which are near the apex; the ventral surface of 
both hind femur and tibia have a dense brush of fine, 
90 
