LIBRARY

Adult Male
Legs - fore and middle coxre
long; trochanters absent;
tarsi isomerous: two- to
four-segmented [five-segmented
in the fossil Mengea
lerliaria (Menge)];
mostly cylindrical; two
claws or none, large pulvillus.
Wings-
Fore wz'ngs - vestigial,
paddle-like or clubshaped;
called halteres.
Hind tIlings - large, fanshaped,
venation reduced.
Spiracles (thoracic) - one
pair mesothoracic
one pair metathoracic
Abdomen - IO-segmented,
base hidden by post-scutellum.
Spiracles - six to eight
pairs.
Gem'talia - male redeagus
straight or hooked and in
a cavity formed by segments
IX and X.
STREPSIPTERA 611
IMPORTANT CHARACTERS-Continued
Adult Female
absent or reduced in family
MENGEIDlE.
absent.
one pair present on mesothorax
in some species.
one pair meta thoracic.
Well developed, unsegmented,
sac-like.
Spiracles-
Free-living forms with
seven pair on abdomen.
Parasitic forms with
one pair on metathorax.
Brood passage - the
ventral space between
the body and the puparium;
slit opening
between head and thorax
of puparium for
fertilization and escape
of young.
Genitalt'a - absent.
I
Larva
three pairs in primary larvre.
Tarsi - variable:
bristle-like with round
or oblong pulviUi.
Absent in older forms.
not evident.
absent.
IO-segmented, clothed
with setre and bristles
and a pair of longer
bristles or setre in primary
larvre.
Segmented and nearly
devoid of setre in later
stages.
Spiracles - none observed.
INTERNAL ANATOMY
The internal anatomy is very imperfectly known. . The brain is well developed.
There is a ganglionic mass and five pairs of nerves in the thoracic
region and another ganglion in the region of abdominal segment III with two
pairs of nerves. . .
In the female the circulatory system is simple and consists of a tubular heart
with nine pairs of ostia and an aorta elttending to the cephalQthoru.