CHAP. IX.] 
GEOLOGICAL CLIMATES. 
195 
Warm Arctic Climates in early Secondary and Palaeozoic times. 
— The evidence we have already adduced of the mild climates 
prevailing in the Arctic regions throughout the Miocene, Eocene, 
and Cretaceous periods is supplemented by a considerable body 
of facts relating to still earlier epochs. 
In the Jurassic period, for example, we have proofs of a mild 
Arctic climate, in the abundant plant-remains of East Siberia 
and Amurland, with less productive deposits in Spitzbergen, 
and at Ando in Norway just within the Arctic circle. But even 
more remarkable are the marine remains found in many places 
in high northern latitudes, among which we may especially 
mention the numerous ammonites and the vertebrae of huge 
reptiles of the genera Ichthyosaurus and Teleosaurus found in 
the Jurassic deposits of the Parry Islands in 77° N. Lat. 
In the still earlier Triassic age, nautili and ammonites in- 
habited the seas of Spitzbergen, where their fossil remains are 
now found. 
In the Carboniferous formation we again meet with plant- 
remains and beds of true coal in the Arctic regions. Lepido- 
dendrons and Calamites, together with large spreading ferns, 
are found at Spitzbergen, and at Bear Island in the extreme 
north of Eastern Siberia; while marine deposits of the same 
age contain abundance of large stony corals. 
Lastly, the ancient Silurian limestones, which are widely 
spread in the high Arctic regions, contain abundance of corals ■ 
and cephalopodous mollusca resembling those from the same 
deposits in more temperate lands. 
Conclusions as to the Climates of Tertiary and Secondary periods. 
— If now we look at the whole series of geological facts as to the 
animal and vegetable productions of the Arctic regions in past 
ages it is certainly difficult to avoid the conclusion that they 
indicate a climate of a uniformly temperate or warm character. 
Whether in Miocene, Upper or Lower Cretaceous, Jurassic, 
Triassic, Carboniferous or Silurian times, and in all the 
numerous localities extending over more than half the polar 
regions, we find one uniform climatic aspect in the fossils. 
This is quite inconsistent with the theory of alternate cold 
and mild epochs during phases of high excentricity, and 
