pecies of _Lasius flavus_ are
naturally more pugnacious than the English species, I know not; if they
are, then this fact will account for the difference in behavior of the
two species to a certain extent, though not entirely.

Others of the social Hymenoptera--for instance, bees and wasps--remember
kindred. On one occasion, I clipped the wings of a wasp, and, after she
had learned that she could no longer fly, placed her on a strange nest.
She was at once attacked, and was soon stung to death. I kept a wasp
confined in a glass for three weeks, carefully feeding her meanwhile,
and then placed her on the nest from which she had been taken. She was
at once recognized by the other wasps, which caressed her with their
antennae, and licked her with their tongues.

Bees, though they seem able to recognize kindred, and to remember them
also for some time, do not show these faculties of the mind as plainly
as do wasps and ants. This is probably due to the fact that bees are a
later development, socially speaking, and are not as psychically mature
as the other social insects.

In the higher animals the memory of kindred, especially in monkeys, is
quite well developed, and is so well known that it does not need
demonstration.

_Memory of Strangers_ (_Animals other than Kin_).--The recognition of
enemies can be noticed in animals quite low in the scale of life, and,
although this psychical phase is almost universally instinctive, it
carries with it certain elements of consciousness. As we ascend the
scale, however, we discover that certain animals are capable of
remembering other animals after a hostile encounter with them; thus, a
pet squirrel remembered the turtle which had bitten him after two years
had elapsed, and a white mouse showed, very plainly, that he had not
forgotten the pet crow from whose clutches he had been rescued, even
after three years had passed by. I might enumerate quite a number of
instances like these, but think it hardly necessary; any one who has
paid any attention to natural history has seen evidences of this phase
of memory in animals. I will, however, give one more illustration of
this form of memory, which, in my opinion, is quite remarkable. In my
front yard, last summer, there dwelt a large colony of bumblebees. One
day, in a moment of idleness, I tossed a tennis ball, with which I was
teaching a young dog to retrieve, into the nest. The dog dashed after
it, scratching up the ground and barking