604 
DIPTERA® 
connected groups has arisen 
requirements of their common 
the Dragon-fly live by chasing 
other insects and catching them 
on the wing, the former sucking 
their juice with its pointed beak, 
the latter chewing them in its 
powerful jaws. Both have a par¬ 
ticularly broad head furnished 
with large eyes ; strong bristly 
grasping legs and feet, large 
wings and a long thin abdomen. 
The utility of strong mouthparts, 
legs and wings is obvious; the 
independently in response to the 
mode of life. Both the Asilid and 
9 cr 
Fig. 396 —The extremity of the 
ABDOMEN IN FEMALE AND 
MALE ASILIDS. 
breadth of the head probably gives its owner greater powers of judging 
the distance of its prey correctly, while the long abdomen helps as a 
balancer and rudder, enabling the insect to turn quickly and accurate^ 
when swooping on its victim. 
The sexes are easily distinguished ; the males always have big clasp- 
ers and the females a pointed ovipositor (fig. 396). The larvae are pro¬ 
bably all predaceous, and with 
the pupae are most often found 
in rotten wood (fig. 397) or in 
earth. The full life-history is not 
known for any Indian species. 
Fig. 397 —Larva of Asilits. after The family comprises some 
.Brauer X 2. 
3,000 known species of which over 
a hundred are recorded from India. It may be divided as follows :— 
(a) Marginal cell closed. 
(1) Antennae with terminal bristle 
(2) Not with terminal bristle .. 
(b) Marginal cell open. 
If without pulvilli, and with slender 
abdomen 
Otherwise 
.. Asilince. 
.. Laphrince . 
.. Leptogaster 
.. Dasypogonince. 
The number of genera is large, and the generic characters often diffi¬ 
cult to distinguish. 
