210 H. H. Howorth—The Fauna and Flora of the Loess. 
Central Europe to Hastern Siberia prove that the climate over this 
wide area must once have been much more uniform than it is now, 
we can also gather from a comparison of many facts that its mean 
was probably lower than it is at present. This seems to point to the 
land having been generally at a higher level; and as it is probable 
that the great beds of till lying between Dunkirk and the Nore, 
famous for the number of Mammoth remains found there, were dry 
land during the Mammoth epoch, we have some evidence that the 
land was, pro tanto, in fact at a higher level than now. 
The general elevation of the land would give the European up- 
lands a more decidedly Northern climate than they now have, with 
corresponding surroundings of fauna and flora. The low-lying 
valleys would not be affected quite so much. This seems to bea 
reasonable view of what was the fact. What then would be the 
result? Assuredly that in the higher ground of Devonshire, of the 
Ardennes, and of Central Germany, we should have upland tracts 
marked by mountain-loving animals and plants, and in the valleys 
have a fauna and flora corresponding to their position; and as the 
areas were small, there would be often a passage to and fro. This is 
what we should expect to find. This is what we actually do find. 
We have a zone marked by low-lying lands stretching from the 
Pyrenees to Behring’s Straits, marked in Post-Glacial times by abun- 
dant remains of the Mammoth and certain other of his companions 
which we know loved the shelter of forests and lived on the leaves 
and shoots of trees, etc.; and we have another zone, including such 
places as Fisherton and the Mendips on the borders of the Devon- 
shire Hills, certain deposits in Auvergne, certain others in Belgium, 
larger ones in Central Germany, and larger ones again in the Aitai, 
as we know from the contents of the caverns there, all marking a 
zone where a more mountainous condition of things both in regard 
to climate and life prevailed. It has been the especial honour and 
privilege of Dr. Nehring to work out this upland fauna, as it 
presents itself in Central Germany, with a completeness, a critical 
skill and knowledge which are simply beyond all praise. I do 
not quite agree with him in describing the particular fauna he 
has explored so well as a “Steppe fauna:” it is rather a hill or 
upland fauna; the particular grassy and herby steppes he refers 
to reproducing because of their climate the surroundings of upland 
pastures. Thus the characteristic habitat of Alactaga jaculus is the 
southern slopes of, and the grassy plains on either side of the 
Urals. It is replaced by other species on the more sterile steppes of 
the Kirghiz Kazaks and Central Asia. The Spermophiles are rather 
inhabitants of hilly rocky districts than of Steppes. This is also the 
case with the Arctomys. In regard to the pikas or tail-less hares 
(Lagomys), this is even more characteristically so, their only present 
habitat in the United States being in the Rocky Mountains. The 
Arvicolg are ubiquitous. Of the pouched rats, one of the two species 
quoted by Dr. Nehring, viz. Cricetus frumentarius, is still found all 
over the European area as far west as the Rhine, and is therefore 
no guide, The porcupines are also hill and fell animals. ‘The 
