show why I hesitate to give the name of memory to the singular faculty
that brings the insect back to her nest with such unerring precision
and yet does not allow her to distinguish her work from some one
else's, however great the difference may be.

We will now experiment with Chalicodoma muraria from another
psychological point of view. Here is a Mason-bee building; she is at
work on the first course of her cell. I give her in exchange a cell
not only finished as a structure, but also filled nearly to the top
with honey. I have just stolen it from its owner, who would not have
been long before laying her egg in it. What will the Mason do in the
presence of this munificent gift, which saves her the trouble of
building and harvesting? She will leave the mortar no doubt, finish
storing the Bee-bread, lay her egg and seal up. A mistake, an utter
mistake: our logic is not the logic of the insect, which obeys an
inevitable, unconscious prompting. It has no choice as to what it
shall do; it cannot discriminate between what is and what is not
advisable; it glides, as it were, down an irresistible slope prepared
beforehand to bring it to a definite end. This is what the facts that
still remain to be stated proclaim with no uncertain voice.

The Bee who was building and to whom I offer a cell ready-built and
full of honey does not lay aside her mortar for that. She was doing
mason's work; and, once on that tack, guided by the unconscious
impulse, she has to keep masoning, even though her labour be useless,
superfluous and opposed to her interests. The cell which I give her is
certainly perfect, looked upon as a building, in the opinion of the
master-builder herself, since the Bee from whom I took it was
completing the provision of honey. To touch it up, especially to add
to it, is useless and, what is more, absurd. No matter: the Bee who