IIO THE AMERICAN NATURALIST. [VoL. XXXV. 
also be questioned whether the willow grouse reached Norway 
at that time, as such an assumption would involve the dilemma 
of either regarding Lagopus scoticus as a reversion since glacial 
times or else of supposing the Scandinavian and the present 
Siberian Lagopus albus to have originated independently and 
yet specifically identically from the brown-winged ancestor, 
none of which propositions I am at present prepared to accept. 
To me it appears most probable that Lagopus scoticus belongs 
to the first Siberian invasion reaching Great Britain and Ireland 
only, but not penetrating to Norway, and that Lagopus albus, 
the white-winged willow grouse, belongs to the second invasion 
entering Scandinavia from the south. I do not know that 
anybody has been able to distinguish the bones of these two 
forms, and it appears most likely to me that the fossil remains 
which Milne-Edwards records from France and Italy as L. albus 
really belong to LZ. scoticus. The occurrence of the latter south 
of the Alps is a fairly good indication that it belonged to the 
first invasion. However that may be, the others must have 
reached Norway, where they still survive, by the above route, 
and while the willow grouse, the Norwegian lemming, and the 
Tundra reindeer died out in central Europe, the remaining 
species, except the musk ox and Cuniculus, saved themselves 
in the southern mountain ranges and in congenial parts of 
Ireland. 
It is quite probable that several other species, members of 
the older Oriental invasion, joined the preglacial Siberian immi- 
gration in France. As one of these I regard the red deer of 
Scotland and Norway, which doubtless forms a small-antlered 
Face, or subspecies, of Cervus elaphus. Its distribution in 
Norway is highly interesting and suggestive, occurring, as it 
does, only along the western coast from Stavanger up to about . 
Namsos (65° north latitude). It is here confined to the outer 
coast lint, chiefly to the larger islands, while it is entirely 
absent in the interior or eastern Norwa 
consequently, 
the west and 
: y. Ibe deer there, 
is restricted to that part of the country lying to 
north of the backbone of the great ice cap which 
extended from southwest to northeast across the Scandinavian 
peninsula during the glacial period. To the south of this ice 
