racted, but it is
superfluous for me to say that they have such means.

Many observations have already been made on the language of insects, and
much diversity of opinion prevails. Very little has been said about the
details of their intercourse, but the consensus of opinion is that they
must in some way communicate among themselves. To me they seem to live
within a world of their own, as other classes of the animal kingdom do.
The means of communication used by mammals could not be available among
aquatic forms, any more than could their modes of locomotion. Each
different class of the animal kingdom is endowed with such characters
and faculties as best adapt them to the sphere in which they live; and
the mode of communication best fitted to the conditions of insect life
would be as little suited to mammals, perhaps, as the feathers of a bird
would be for locomotion in the realm of fishes.

[Sidenote: LANGUAGE OF INSECTS]

I am aware that some high authorities have claimed that insects
communicate by sounds. My own opinion is that they employ a system of
grating or scratching by means of their stigmata, but that the sound
created thus performs no function in the act of communicating, but is
only a bi-product, so to speak, and that the jarring sensation
transmitted through the air is the real means by which they understand
each other, possibly somewhat like telegraphy, in which the sounds are
not modulated, but are distinguished by their duration and the interval
between them. I do not announce this as conclusive, but merely suggest
it as a possible key to their mode of intercourse.

[Sidenote: A COLONY OF ANTS]

I have observed that signs prevail to a great extent among ants. Some
years ago I had an opportunity of studying a colony of ants, and I
watched them almost daily for several weeks. I had seen it stated that
they found their way by the sense of smell, but these observations
confirmed my doubts on that point, and I feel justified in saying that
they are guided almost, if not entirely, by landmarks. On the bark of a
tree from which they were gathering in their winter stores, I observed
that there were certain little knots or protuberances by which they
directed their course and which they always passed in a certain order.
Between these landmarks they did not confine themselves to any exact
path, but the concourse would sometimes widen out over the space of more
than an inch, but as they approached a landmark