of the Polar Regions. 63 
lied to S. sempervirens, from which it is distinguished only by 
the size of its cones, which are larger and composed of more 
scales. Sequoia Sternbergii, which was abundant in Iceland, 
is very nearly related to S. gigantea; whilst S. Couttsie, 
which is found in Greenland, at Disco and Ataneverdlak, is 
intermediate between S. Langsdorffii and S. Sternbergit. The 
family of the Cypresses is richly represented by three genera— 
Taxodium, Thujopsis, and G‘lyptostrobus. ‘The latter two are 
still in existence in Japan; the Tawxodia occur in North 
America. Glyptostrobus europeus usually accompanies the 
Sequoia Langsdorffit, as also does Taxodium dubium, of which 
the branches, leaves, and cones were discovered at Atane- 
verdlak, and which has also been found ou Spitzbergen, at 
about 78° N. latitude. Thwopsis ewropea is much rarer; its 
elegant branches have been found in North Greenland, and 
they are identical with those obtained from amber and at 
Armillan (near Narbonne). 
Among the 'l'axineze we remark a Salisburia from Green- 
land; this genus now occurs in the wild state only in Japan. 
The number of leafy trees is so considerable that we can 
_ only indicate a few species. Several of them resemble trees 
mr: 
‘3 ¥ 
S 
ee 
a 
ei 
E 
4 
ae 
Rs 
a 
4 
. 
ey 
9 
a 
= 6 
ies 
of our countries; such are the Beeches and Chestnuts, which 
are still found in North Greenland at 70° N. latitude. A 
species of Beech (Fagus Deucalionis) is extremely near our 
common Beech (Fagus sylvatica) ; the leaves are of the same 
form and dimensions, and have the-same nervures, but they 
are denticulated only at the extremity. This tree was, ap- 
parently, diffused through all the northern regions, since we 
meet with it in Greenland, Iceland, and Spitzbergen. The 
Oaks are still more varied; we count eight species in’ Green- 
land, most of them having large, elegantly denticulated leaves ; 
they have some relation to American species. One of them 
(Quercus Olafsoni), which may be traced from the north of 
Canada to Greenland and Spitzbergen, is the analogue of 
Quercus prinus of the United States. A Platanus (P. ace- 
roides) was also spread over all these countries; it is even 
met with in the Hisfjord in Spitzbergen. The Poplars fur- 
nish a still greater number of individuals than the genera just 
cited. ‘Two species (Populus Richardsoni and P. arctica), with 
Sequoia Langsdorgfii, were the commonest trees of the polar 
zone. We can trace them from the Mackenzie to Spitzbergen. 
The Willows are very rare, which may well surprise us when 
_we consider that they now form one-fourth of the woody plants 
of the arctic zone. The Birches were abundant in Iceland, 
where we also remark a fine species of Tulip-tree and a Maple 
(Acer otopteryx). In Greenland we find a Walnut, a Mag- 
