'Descend!' and they all dropped nearly to the ground.

'Forage!' and they alighted and scattered about to feed, while two
of the permanent sentries mounted duty--one on a tree to the right,
the other on a mound to the far left. A minute or two later
Silverspot would cry out, 'A man with a gun!' The sentries repeated
the cry and the company flew at once in open order as quickly as
possible toward the trees. Once behind these, they formed line
again in safety and returned to the home pines.

Sentry duty is not taken in turn by all the crows, but a certain
number whose watchfulness has been often proved are the
perpetual sentries, and are expected to watch and forage at the
same time. Rather hard on them it seems to us, but it works well
and the crow organization is admitted by all birds to be the very
best in existence.

Finally, each November sees the troop sail away southward to
learn new modes of life, new landmarks and new kinds of food,
under the guidance of the everwise Silverspot.

III

There is only one time when a crow is a fool, and that is at night.
There is only one bird that terrifies the crow, and that is the owl.
When, therefore, these come together it is a woeful thing for the
sable birds. The distant hoot of an owl after dark is enough to
make them withdraw their heads from under their wings, and sit
trembling and miserable till morning. In very cold weather the
exposure of their faces thus has often resulted in a crow having