6 
Proceedings of the Royal Society of Edinburgh. [Sess. 
other forms. The northern group included the reindeer, the musk sheep, 
the Alpine hare, the lemming, the extinct mammoth, and woolly rhinoceros. 
The temperate group contained the Irish elk, the bison, the grizzly bear, 
the cave bear, and other forms. 
His arguments against the migration theory are best given in his own 
words : — 
“ The migrations of land animals in Northern Asia and equivalent 
latitudes in North America take place between Arctic and temperate 
regions. This is simply the case of adjacent provinces overlapping one 
another. Inasmuch, therefore, as the migration theory asks us to believe 
that widely separated zones overlapped across the whole breadth of the 
temperate provinces, it is unreasonable, and not supported by our know- 
ledge of what actually occurs in nature. 
“ The general character of the southern group of mammalia, as exhibited 
in cave deposits and river gravels, is non-migratory. 
“ The union of Britain and Ireland to the continent, across the upraised 
beds of the English Channel and the Irish Sea, and a great increase of 
land within the area of the Mediterranean, could not confer upon Europe 
a climate in any degree approaching to that of Siberia or British America. 
The climate of our continent would still be insular, and consequently great 
migrations could not take place. 
“ During the last continental condition of our islands, snow-fields and 
glaciers existed in our mountain regions, betokening a climate quite un- 
suited to the needs of the southern mammalia. The winters at that period 
must have been excessive, and the summers cold and ungenial. 
“ Lastly, so long as the Atlantic continues to wash the coast of Europe, 
and so long as the present configuration of the land endures, our continent 
must continue to enjoy an insular climate, and there is not the slightest 
physical evidence to show that it possessed any other kind of climate 
during the period that the southern mammalia inhabited Britain.” 
With reference to the age of the Palaeolithic deposits, James Geikie 
concluded that they are preglacial or interglacial and not post-glacial. 
In the midland and northern counties of England, in Wales, Scotland, and 
Ireland, which had been subjected to the grinding action of land ice, these 
deposits are either absent or sparingly represented. But in those regions, 
such as the Thames valley, which had not been overridden by the ice, the 
valley gravels furnish a continuous record from preglacial times to the 
present day. Between Palaeolithic and Neolithic times there was a 
great gap which coincided with a period of submergence. Thereafter, the 
new stone men entered Britain accompanied by a distinct mammalian 
