juices
of plants as do the females when they cannot get blood. It is not at all
necessary for mosquitoes to have the warm blood of man or other animals.
Comparatively few of them ever taste blood. They have been seen feeding
on blossoms, ripe fruit, watermelons, plant juices, etc. They are very
fond of ripe bananas and are fed on them in the laboratory when we wish
to keep mosquitoes for experimental purposes.

THE THORAX

The middle part of the body, called the thorax, is really a strong box
with heavy walls for the attachment of the powerful wing and leg
muscles. The three pairs of legs are covered with hairs and scales, and
their tips are provided with a pair of claws which vary somewhat in the
different species. The wings (Fig. 68) are long and narrow with a
characteristic venation. Along the veins and the margin of the wings are
the scales which readily enable one to distinguish mosquitoes from other
insects that may look much like them. In some species these scales are
long and narrow, almost hair-like, in others they are quite broad and
flat (Fig. 69). Just back of the wings is a pair of balancers, short
thread-like processes knobbed at the end. These probably represent the
second pair of wings with which most insects are provided, and seem to
serve as balancers or orienting organs when the insect is flying. On the
sides of the thorax are two small slit-like openings, the
breathing-pores. These are the openings into the tracheal or respiratory
system.

THE ABDOMEN

The long cylindrical abdomen is composed of eight segments. These are
rather strongly chitinized above and below, but a narrow strip along the
side is unchitinized. In this strip are situated the abdominal
breathing-pores. The tip of the abdomen is furnished with a pair of
movable organs, which in the male are variously modified and serve as
clasping organs at mating time.

THE DIGESTIVE SYSTEM

The mouth-parts of the mosquito have just been described. It will be
remembered that the labrum is provided with a groove. Through this the
blood or other food is sucked up by means of a strong-walled pumping
organ, the pharynx, situated in the head (Fig. 70). Just back of the
pharynx is the esophagus which leads to the beginning of the stomach.
Close to its posterior end the esophagus gives off three food
reservoirs, two above and a single larger one below. In dissections
these will often be seen to be filled with minute bubbles. The stomach
rea