202 ISLAND LIFE 



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 vertebraB 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 

 inhabited the seas of Spitzbergen, where their fossil re- 

 mains are now found. 



In the Carboniferous formation we again meet with 

 plant-remains and beds of true coal in the Arctic regions. 

 Lepidodendrons and Calamites, together with large spread- 

 ing 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 abund- 

 ance of corals and cephalopodous moUusca 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, Carbonif- 

 erous 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 persistent 

 cold epochs when the excentricity was as low as it is now 

 or lower, for that would imply that the duration of cold 

 conditions was greater than that of warm. Why then 

 should the fauna and flora of the cold epochs never be 



