also for the safety of the individual, and for providing it with
the necessary food. With many large divisions of the animal
kingdom mutual aid is the rule. Mutual aid is met with even
amidst the lowest animals, and we must be prepared to learn some
day, from the students of microscopical pond-life, facts of
unconscious mutual support, even from the life of
micro-organisms. Of course, our knowledge of the life of the
invertebrates, save the termites, the ants, and the bees, is
extremely limited; and yet, even as regards the lower animals, we
may glean a few facts of well-ascertained cooperation. The
numberless associations of locusts, vanessae, cicindelae,
cicadae, and so on, are practically quite unexplored; but the
very fact of their existence indicates that they must be composed
on about the same principles as the temporary associations of
ants or bees for purposes of migration. As to the beetles, we
have quite well-observed facts of mutual help amidst the burying
beetles (Necrophorus). They must have some decaying organic
matter to lay their eggs in, and thus to provide their larvae
with food; but that matter must not decay very rapidly. So they
are wont to bury in the ground the corpses of all kinds of small
animals which they occasionally find in their rambles. As a rule,
they live an isolated life, but when one of them has discovered
the corpse of a mouse or of a bird, which it hardly could manage
to bury itself, it calls four, six, or ten other beetles to
perform the operation with united efforts; if necessary, they
transport the corpse to a suitable soft ground; and they bury it
in a very considerate way, without quarrelling as to which of
them will enjoy the privilege of laying its eggs in the buried
corpse. And when Gleditsch attached a dead bird to a cross made
out of two sticks, or suspended a toad to a stick planted in the