234 FOREST LANDS OF NORTHERN RUSSIA. 
inadequacy of the views of Hutton and Count Saporta to 
account for past changes of temperature. He states 
that the theory which now meets with most acceptance is 
that which attributes climatic changes to astronomical 
causes, and especially to the eccentricity of the earth’s 
orbit—a theory associated with the name of Dr Croll, of 
the Geological Survey of Scotland. At the same time, in 
regard to the facts in which we are here concerned, he 
says :— 
T Bostdde the tale of intolerable cold brought home by 
Arctic expeditions, which, in the concrete form of thick- 
ribbed ice and perpetual snow, has hitherto effectually 
barred their approach to the Pole, they seldom fail to 
secure satisfactory evidence of the former existence of 
more genial conditions in circumpolar lands. Pine trees 
have been found prostrate on the site of their growth in 
greatly higher latitudes than those in which they could 
now exist, and these, from their still unfossilised condition, 
give evidence of having lived and died within com- 
paratively recent times. That much warmer conditions 
prevailed at a still earlier time is evidenced by the fossil 
plants found in some of the highest lands yet reached. 
These include many evergreen shrubs, oaks, maples, 
beeches, poplars, and walnuts; while two species of vines 
have been found fossil in Greenland ; sequozas, allied to 
the mammoth trees of the Yosemite region of California 
in Spitzbergen ; with water lilies and the swamp-cypress 
of the Southern United States in Grinnell Land, within 
eight degrees ofthe Pole. Judged by its plant remains, 
Greenland would appear to have possessed in miocene, or, 
as many geologists are now inclined to believe, in eocene 
times, a climate as warm as that of New York or St. 
Louis, and a vegetation richer than that of Southern 
Europe at the present time, while the Pole itself, or at 
least its near neighbourhood, would probably have com- 
pared favourably in climate and vegetation with Scotland 
of to-day. Geologists are agreed in regarding the presence 
of such a flora as conclusive evidence of the former existence 
