568 
DIPTERA. 
Fig. 366 -ANOPHELES LARVA RESTING AT THE SURFACE, PARTLY SUSPENDED BY ITS PALMATE HAIRS. MUCH ENLARGED. 
(After limns.) 
to swim when they wish to leave the surface. Unlike the Culex 
larvae, they rarely seek the bottom except when frightened. They 
have the curious habit of often feeding with the head turned completely 
round on the neck, so that what looks as if it were the top of the head is 
really the under side. While the Culicine larva thus hangs in the 
water head downwards, the adult Culex mosquito has the body roughly 
horizontal when at rest, the 
thorax being the highest point, 
while the Anopheles mosquito 
(whose larva lies horizontal) sits 
with the head, thorax, and ab¬ 
domen in one straight line, the 
head down and the tail up, as in 
Fig. 368. (N.B .—The female 
Myzomyia culicifacies, an Anop- 
heline, sits like a Culex.) When 
the larvae pupate, which they do 
after two or three moults, the 
whole elaborate breathing appar¬ 
atus at the tail end disappears, and 
its place is taken by two trumpet¬ 
shaped spiracles projecting from 
the thorax which supply air to 
the tracheae when the pupa is 
vufi/ 
Fig. 367— -Head and thorax of an 
A NOPHELINE LARVA X about 16. 
{After Jtunes and Liston.) 
