larger than the thorax and head together. (Fig. 12.) On this
distended receptacle appear several darker plates; these are the
remains of the chitinous parts of the primitive wings. In the fine
season these ants go out in a band and collect a sweet liquor which
forms pearly drops on certain galls of oak leaves. These drops,
elaborated into honey, gradually fill the crop, distending it and
pushing back neighbouring organs until it receives its globular form.
When they have arrived at this obese condition, the heavy honey ants
no longer leave the nest. They remain without movement, hanging by
their legs to the roof or lying against the walls of a room. The
workers who have remained slender come and go, attending to their
usual occupations, and pass near the others without paying attention
to them or going out of the way to lend assistance to their impotent
sisters when one of them has rolled over on the ground and can no
longer arise unaided. (Fig. 13.) They only cease to be indifferent
when impelled by the selfish sentiment of hunger, and then it is to
ask and not to give assistance. The fat ants in fact could not
themselves consume all the honey that they have elaborated; the others
in times of famine approach them, caress them with their antennae, and
obtain by solicitation a drop of honey which the large ones disgorge
from the crop. Here, then, is a colony in which the division of labour
has reached a remarkable degree of polymorphism. Some of the members
accomplish the work of engineers and masons, while the others
fabricate for the community a store of honey. Instead of depositing
these provisions in cells like bees, they preserve them in their own
digestive tube. This custom has re-acted to such an extent on the form
of their bodies that at first sight they seem to belong to a different
species.

[Illustration: FIG. 14.]

_Animals who submit foods to special preparation in order to
facilitate transport._--Not content with collecting materials as they
are found in nature, certain animals submit them to preparation with
various aims, either to render transport easier or that they may not
deteriorate when stored. Among those of whom I have just spoken, some
collect with the view of utilising their stores in a more remote
future than others. The _Ateucus sacer_ intends to consume the
provisions he prepares almost immediately. Yet he acts in so careful a
manner that I cannot pass him in silence. This beetle is the sacr