Another species (the Eciton legionis) has been known to attack other
ants' nests for the sake of plunder. Mr Bates saw an army of them
employed on the face of an inclined bank of earth. They were excavating
mines to get at the nest of a larger species of ant of the genus
Formica. Some were rushing into the passages, others were seen
assisting their comrades to lift out the bodies of the formicae, while
others were tearing them in pieces--their weight being too great for
that of a single eciton. A number of carriers then seized each a
fragment and carried it down the slope. When the naturalist dug into
the earth with a small trowel, the eager freebooters rushed in as fast
as he excavated, and carried off the ants, so rapidly tearing them in
pieces that he had great difficulty in rescuing a few entire specimens.
The little ecitons seemed to be divided into parties, some excavating,
others carrying away the grains of earth. When the shafts became rather
deep, the mining parties had to climb up the sides each time they wished
to cast out a pellet of earth; but their work was lightened by their
comrades, who stationed themselves at the mouth of the shaft and
relieved them of their burdens, carrying the particles to a sufficient
distance from the edge of the hole to prevent them rolling in again.
All the work seemed thus to be performed by intelligent co-operation
among the host of eager little creatures. Still, there was not a rigid
division of labour; for some of them, whose proceedings he watched,
acted at one time as carriers of pellets, and at another as miners, and
all shortly afterwards assumed the office of conveyers of the spoil. In
about two hours, all the nests of the formicae were rifled.
He frequently saw these little creatures engaged apparently in play, in
the neighbourhood of their homes. Some were walking slowly about,
others were brushing their antennae with their fore-feet; but the
drollest sight was to see them cleaning one another. Here and there an
ant was seen stretching forth first one leg, then another, to be brushed
or washed by one or more of its comrades; who performed the task by
passing the limb between the jaw and the tongue, finishing by giving the
antennae a friendly wipe.
There are two species of blind ecitons--which, however, go on foraging
expeditions, and even attack the nests of other stinging species; but,
avoiding the light, they move always under leaves and fallen branches:
when the columns have to pass a cleared space, the ants form covered
ways with granules of earth, arched over and holding together
mechanically.