cene times--to Asia and
North America, where a large number of new species originated. It seems
to me even probable that one of these Asiatic species of _Sorex_, viz.
_S. araneus_ (_vulgaris_), subsequently migrated towards the old home of
its forefathers, since we find it more or less confined to Central and
Northern Asia and Northern Europe.

Though the origin of the Alpine Hare has already been referred to and
fully discussed in a previous chapter (p. 148), the conclusions arrived
at may be once more repeated. The Alpine Hare (_Lepus variabilis_) is of
Arctic origin. It spread southward into Europe, North America, and Asia
in early glacial times, and reached our continent from Spitsbergen by
means of a direct land-connection with Lapland. The Scandinavian
peninsula was then separated from Russia, but connected with Scotland
and Ireland (Fig. 13, p. 170). Since England was then united to France,
the Alpine Hare was able to invade western continental Europe and all
the mountain ranges. Its range is very discontinuous, small colonies
being scattered all over the mountainous parts of the Northern
Hemisphere, while the European Hare--a closely allied species--occurs in
the plain, and now occupies to some extent the former haunts of the
Alpine Hare (cf. Fig. 8, p. 137). Might not the European Hare, as
suggested, possess some advantages which enabled it to drive the other
into more inaccessible parts, thus producing the peculiarity of range?
The present distribution of the Alpine and the European Hare (_L.
Europaeus_) appears to me to strongly support such an assumption. It is
not the cold which has driven the Alpine Hare to the Alps; and its
presence there is not, as is often supposed, a "_standing testimony of a
former arctic climate_" in Europe, but merely the necessary consequence
of the weaker species being thrust into less accessible regions by a
stronger rival.

_Muscardinus avellanarius_,--the common Dormouse,--though by no means
confined to the Alps, has probably originated there. It is found up to a
height of nearly 5000 feet in these mountains, and is spread over Europe
at nearly equal distances from the Alps in all directions. Being absent
from Ireland, Scotland, Norway, and Northern Russia, it seems as if it
had only diffused northward in more recent times.

The closely allied genus _Myoxus_ is likewise of European extraction,
some species being known from French eocene deposits.

There are only a few typic