96 THE AMERICAN NATURALIST. [VOL. XXXV. 
standpoint of the biologists, against the view that would ascribe 
to the glacial period so severe a cold and so enormously and 
universally developed an ice sheet, or ice cap, that all life 
became extinct and every inch of ground hidden by a thick 
covering of perpetual ice. I doubt, however, that this is 
currently believed by the biologists of to-day. I do not think 
I am much out of the way when I say that most of us regard 
the conditions and climate of the Ice Age in Europe to have 
been on the whole much like the conditions and climate of 
Greenland and the island world north of Hudson Bay at 
the present time. It would therefore be possible for us to 
subscribe to Dr. Scharff's conclusion as above worded were 
it not that in the book itself he goes much farther, requiring, 
as he does, a climate in central Europe at least as mild as 
that of the present day or even milder. The present reviewer 
at least cannot admit that the known facts relative to the dis- 
tribution of animals and plants during Pliocene and Pleisto- 
cene times require such a hypothesis for their satisfactory 
explanation. 
It may be true *that with a comparatively slight change of 
the atmospheric conditions in the British Islands, we might 
have glaciers back again on all our highest ranges in England, 
Scotland, and Ireland" (p. 69), and it may also be true that 
Falsan, whom Dr. Scharff quotes with evident approval, is 
right when he says “that the mean annual temperature of 
France during the glacial period was approximately from 
6-9" C. perhaps more. This," Dr. Scharff continues, “is 
the actual mean annual temperature of the southwest of 
Sweden and Norway, or the north of Scotland." Of course 
this statement is correct enough, but the whole question 
assumes a somewhat different aspect when we consider that 
nu M - Falsan means a lowering of the 
cR Nn c. riim s * This would mean for Berlin 
Vienna, a January isotherm lik genae gemis uan 
Gobat qid dt dust " et vi of the south end of 
between Sitka and the Ali aa we Pipetite ae 
laska peninsula. Under the same 
conditions Edinburgh would have a summer like the extreme 
