34 Dr. J. Croll on Aretic 
oxen, and sheep in such abundance that these animals must 
formerly have lived there in large herds. At present, how- 
ever, the icy wilderness produces nothing that could afford 
them nourishment, nor would they be able to endure the 
climate. Sannikow concludes that a milder climate must 
formerly have prevailed here, and that these animals may 
therefore have been contemporary with the Mammoth, whose 
remains are found in every part of the island.” * 
‘‘ Herr von Ruprecht reported to Brandt that, at the mouth 
of the Indiga, in 67° 39’ N. lat., on a small peninsula called 
Chernoi Noss, where at present only very small birch bushes 
grow, he found rotten birch trunks still standing upright, of 
the thickness of a man’s leg and the height of aman. In 
going up the river he met with no traces of wood until he 
reached the port of Indiga. Here he noticed the first light- 
fir woods growing among still standing but dead trunks. And 
higher up the river still, the living woods fairly began.” f 
Schmidt says that, “‘ where the lakes on the tundra have 
grown small and shallow, we find on and near their banks a 
layer of turf, under which, in many places, are remains of trees 
in good condition, which support the other proofs that the northern 
limit of trees has retrogressed, and that the climate here has grown 
colder. I found, on the way from Dudino to the Ural Moun- 
tains, ina place where larches now only grow in sheltered river- 
‘valleys, in turf on the top of the tundra, prostrate larch trees 
still bearing cones.’’t 
Schmidt also states that he was informed that at Dudino, 
just at the limit of the woods, there had been found in a 
miserable larch wood the lower part of a stem sticking in the 
ground, apparently rooted, which was three feet in diameter. 
He also states that, “eleven versts above Krestowkoje, in 
lat. 72°, he found, in a layer of soil covered with clay on the 
upper edge of the banks of the Yenissei, well-preserved stems 
like those of the birch, with their bark intact, and sometimes 
with their roots attached, and three to four inches in diameter. 
Professor Merklin recognizes them as those of the Alnaster 
fruticosus, which still grows as a bush on the islands of the 
Yenissei, in lat. 704° N.” | 
Evidence from Shells.—In the freshwater deposits in which 
the bones of the’ Mammoth are found, there are freshwater- 
and land-shells, which indicate a warmer condition of climate. 
I quote the following from Mr. Howorth’s memoir :— 
“ Schmidt found “Helix schrencki in freshwater deposits on 
* Wrangell, p. 496. 
+ Bull. of Soc. of Nat. of Moscow; quoted by Howorth. 
t Schmidt, as quoted by Howorth. 
