expanses of water. To enable them to do this in the winter, the frog of
the foot is almost entirely absorbed, and the edges of the hoof, now
quite concave, grow out in sharp ridges, each division on the under
surface presenting the appearance of a huge mussel-shell, and serving
the office of natural skates. So rapidly does the shell increase, that
the frog does not fill up again till spring, when the antlers bud out.
With this singular conformation of the foot, it has a lateral spread;
and an additional assistance for maintaining a foothold on slippery
surfaces is given by numerous long, stiff bristles which grow downward
at the fetlock, curving over entirely between the divisions. The
cariboo is thus enabled to proceed over the snow, to cross frozen lakes,
or ascend icy precipices, with an ease which places him, when in flight,
beyond the reach of all enemies, except perhaps the nimble and untiring
wolf.

The cariboo is essentially a migratory animal. There are two
well-defined periods of migration, in the spring and autumn. Throughout
the winter it appears also seized with an unconquerable desire to change
its residence. One day it may be found feeding quietly through the
forests in little bands, and the next, perhaps, all tracks show a
general move in a certain direction. The animals join the main herd
after a while, and entirely leaving the district, travel toward new
feeding-grounds. Though often found in the same woodlands as the moose,
they do not enjoy each other's company. In severe winters the cariboos
travel to the southernmost limits of their haunts, and even sometimes
enter the settlements. Not being aquatic, like the moose, to avoid the
flies in summer they ascend the mountain ranges, where they can be free
from their attacks. The hunter, however, follows them, and their speed
being of no avail among the precipices, many are shot. During most of
the year the flesh of the animal is dry and tasteless; but it possesses
a layer of fat, two or more inches thick, which is greatly esteemed.
This, with the marrow, is pounded together with the dried flesh, and
makes the best kind of pemmican--a food of the greatest value to the
hunter. The cariboo lives in herds, sometimes only of ten or twenty,
but at others consisting of thirty or more individuals. They range
across the whole width of the continent, being found in great numbers to
the west of the Rocky Mountains, especially at the northern end of
B