AO Dr. J. Cro! on Arctic 
During the continuance of the ten or twelve thousand years 
of Arctic conditions it would find in Southern Hurope and 
elsewhere places where it could exist. At the end of the cold 
period, and when the climate again began to grow mild and 
equable, it would retrace its steps northwards. There is, 
however, little doubt that during the severity of a glacial 
period, and when necessarily confined to a more limited area, 
its numbers would be greatly diminished. There is every 
reason for believing that the Mammoth outlived all that suc- 
cession of cold and warm periods known as the glacial epoch 
proper, and did not finally disappear till recent postglacial 
times. 
It was probably about the commencement of a cold period, 
and before the Mammoth had retreated from Northern Siberia, 
that those individuals perished whose carcases have been found 
frozen in the cliffs. The way in which they probably perished 
and became imbedded in the frozen mud and ice, has, I think, 
been ingeniously shown by Dr. Rae*. 
Arctic America during Interglacial times.—We have seen 
that the eastern continent in Pleistocene times enjoyed in the 
Arctic regions interglacial conditions of climate. It is true 
that on the western continent we have not in Arctic regions 
such clear and satisfactory evidence of an interglacial period. 
But it would be rash to infer from this that the western con- 
tinent was, in this respect, less favoured than the eastern. 
That we should find less evidence at the present day of former 
interglacial periods in Arctic America than in Arctic Asia, is 
what is to be expected, for the glaciation which succeeded 
interglacial periods has been far more severe in the former 
region than in the latter. The remains of the Mammoth 
have, however, been found in Arctic America, in ice-cliffs at 
Kotzebue Sound, under conditions exactly similar to those of 
Siberia. 
In Banks’s Land, Prince Patrick’s Island, and Melville 
Island, as in Northern Siberia, full-grown trees have been 
found in abundance at considerable distances in the interior, 
and at elevations of two or three hundred feet above sea-level. 
The bark on many of them was in a perfect state. Capt. 
McClure, Capt. Osborn, and Lieut. Mecham, by whom they 
were found, all agreed in thinking that they grew in the place 
where they were found. 
It is true that more recent Arctic voyagers have come to 
the conclusion that these trees must have been drifted down 
the rivers from the south. There can be little doubt that the 
greater part of the wood found there, as in Siberia, is drift- 
wood. But may there not be also, as in Siberia, two kinds 
* Phil. Mag. for July 1874, p. 60. 
