while
in the air being peculiar in that they usually rise and fall in the
same vertical line--performing a curious aerial dance which is long
continued.

Among the dozen or more butterflies and moths which winter in the
perfect state, the most common and the most handsome is the
"Camberwell beauty" or "mourning cloak," _Vanessa antiopa_ L., a large
butterfly whose wings are a rich purplish brown above, duller beneath,
and broadly margined with a yellowish band. It is often found in
winter beneath chunks which are raised a short distance above the
ground, or in the crevices of old snags and fence rails. It is then
apparently lifeless, with the antennae resting close along the back,
above which the wings are folded. But one or two warm days are
necessary to restore it to activity, and I have seen it on the wing as
early as the 2d of March, hovering over the open flowers of the little
snow trillium.

All the species of ants survive the winter as mature forms, either in
their nests in the ground or huddled groups in half rotten logs and
stumps; while here and there beneath logs a solitary queen bumble-bee,
bald hornet, or yellow jacket is found--the sole representatives of
their races.

Thus insects survive the winter in many ways and in many places, some
as eggs, others as larvae, still others as pupae, and a large number as
adults--all being able to withstand severe cold and yet retain
vitality sufficient to recover, live, grow, and replenish the earth
with their progeny when the halcyon days of spring appear once more.

In the scale of animal life the vertebrates or back-boned animals
succeed the insects. Beginning with the fishes, we find that in late
autumn they mostly seek some deep pool in pond or stream at the bottom
of which the water does not freeze. Here the herbivorous forms eke out
a precarious existence by feeding upon the innumerable diatoms and
other small plants which are always to be found in water, while the
carnivorous prey upon the herbivorous, and so maintain the struggle
for existence. The moving to these deeper channels and pools in autumn
and the scattering in the spring of the assembly which has gathered
there constitute the so-called "migration of fishes," which is far
from being so extensive and methodical as that practiced by the
migratory birds.

Many of the smaller species of fishes, upon leaving these winter
resorts, ascend small, clear brooks in large numbers for the purpose
of depo