620 
blfTEHA. 
Body nearly bare, or furry, head and face 
rather large, mouth-parts and antennae very 
small .. . . .. . . Oestrids. 
We have included Oestridce among calyptrate muscoids, though 
they are better regarded as a separate group, originally composed of 
several muscoid types and now much specialised for a parasitic 
existence. 
Conopim. 
Rather elongate flies, abdomen often with a distinct waist, the tip some¬ 
times thickened and turned under. Head large and broad, the eyes 
well separated in both sexes. Antennce 3- jointed, prominent, with a 
dorsal arista or a terminal style. A slender, often jointed, proboscis, 
wings often coloured ; anal cell closed ; ls£ posterior cell closed or 
nearly closed. 
The Conopidce are unlike most of the other acalyptrates in having 
the 1st posterior cell often closed, and partly for this reason they are 
frequently classed with the Aschiza ; they have, however, a ptilinum 
and frontal suture which indicates that they are really Schizophora. 
These flies are usually fairly large, and are found about flowers, 
where they are easily mistaken for Hymenoptera. Their bodies are 
usually devoid of bristles or noticeable 
hairs, but often bear a glistening coat of 
short golden pubescence, and are fre¬ 
quently coloured rather conspicuously 
with yellow, reddish brown, or black. 
Their flight is not particularly rapid. 
Economically they are of some slight in¬ 
terest, as they are parasitic on Hymen¬ 
optera such as Wasps and Bumble-bees, and also apparently on 
locusts (in America). According to Williston, the Conopid chases 
the bee and lays an egg upon its body during flight. The larva on 
hatching burrows into the abdomen of the bee, where it remains and 
pupates, the adult fly emerging from between the abdominal segments 
of its unfortunate host. As a rule the larvse are oval and rounded, 
with distinct segments, on the last of which are two large round 
Fig. 408— Conopid larva, 
AFTER BRAUER X 5. 
