in northern Europe and Asia, and two others, a northern and a southern,
in North America, but lately the last two have been subdivided, and the
present practice is to regard the Scandinavian reindeer (_Rangifer
tarandus_) as the type, with eight or nine other species or
sub-species, consisting of the two longest known American forms, the
northern, or barren-ground caribou (_R. arcticus_); the southern, or
woodland (_R. caribou_); the three inhabiting respectively
Spitzbergen, Greenland and Newfoundland, and still more lately four more
from British Columbia and Alaska. The differences between these are not
very profound, but they seem on the whole to represent two types: the
barren-ground, small of size, with long, slender antlers but little
palmated; and the woodland, larger, with shorter and more massive
antlers, usually with broad palms. There is some reason to believe that
both these types lived in Europe during the interglacial period, the
first-named being probably the earlier and confined to western Europe,
while the other extended into Asia. The present reindeer of Greenland
and Spitzbergen seem to agree most closely with the barren-ground, while
the southern forms are nearest to the woodland, and these are said to
also resemble the reindeer of Siberia. It is, therefore, not an
improbable conjecture that there were two migrations into America, one
of the barren-ground type from western Europe, by way of the Spitzbergen
land connection, and the other of the woodland, from Siberia, by way of
Alaska.

Little more can be said, perhaps even less, of the other circumpolar
genus, _Alces_, known in America as "moose," and across the
Atlantic as "elk." It also is of mixed character in relation to the two
great divisions we have had in mind, but in a different way from
reindeer.

Like American deer it has the lower ends of the lateral metacarpals
remaining, and the antlers are without a brow-tine, but like
_Cervus_ it has an incomplete vomer, and unlike deer in general,
the antlers are set laterally on the frontal bone, instead of more or
less vertically, and the nasal bones are excessively short. The animal
of northern Europe and Asia is usually considered to be distinct from
the American, and lately the Alaskan moose has been christened _Alces
gigas_, marked by greater size, relatively more massive skull, and
huge antlers. Of the antecedents of _Alces_, as in the case of the
reindeer, we are ignorant. The earlier Ple