ON" THE VALUE OF THE FOSSIL FLORAS OF THE ARCTIC 

 REGIONS AS EVIDENCE OF GEOLOGICAL CLIMATES. 1 



By Prof. A. G. Nathorst, of Stockholm. 

 Translated from the French original 2 by E. A. Newell Arber, M. A., F. G. S. 



Among the problems which are constantly called to mind during 

 geological explorations in the Arctic regions, that of the climates of 

 the past naturally demands special attention. The contrast between 

 the present and the past is there more striking than in any other 

 region. Beneath the snow and ice bordering the Arctic Sea one 

 marvels to find, for example, large corals in beds belonging to the 

 Carboniferous system, or again the remains of saurians, ammonites, 

 or nautiloids in those of Triassic age. But when one bears in mind 

 the extreme richness of the invertebrate fauna of the Arctic Seas 

 to-day, when one remembers the colossal whales which find their 

 subsistence in these waters, one may be inclined to ask if it has not 

 been an error to conclude, from the occurrence of the fossils above 

 mentioned, that the climate was formerly more genial than it is to-day. 

 Should we not be underestimating the creative power of life if we 

 imagine that, among the saurians, the ammonites, and the nautiloids, 

 no species has been able to develop which was adapted to life in the 

 Arctic Seas ? If the reindeer and the musk ox were extinct, who 

 would imagine that these beasts were able to flourish on the scanty 

 vegetation of the high parallels north of 80° of latitude? And who 

 would suppose that such monsters as the mammoth and the woolly 

 rhinoceros could find sufficient nourishment in the poor vegetation 

 of the tundras or the coriferous forests ? Such examples teach pru- 

 dence; there is certainly no question which requires so much caution 

 as the problem of deducing from the faunas of the past the climatic 

 conditions under which they flourished. 



This remark applies with equal force to the floras. Although 

 to-day the cycads only occur in warm regions, it would be an error 



1 A paper read before the Eleventh International Geological Congress on Aug. 25, 1910. "Sur la valeur 

 des flores fossiles des regions arctiques comma preuve des climats geologiques," Stockholm, 1910. Also in 

 Compt. Rend. Eleventh Intern. Geol. Congr., Stockholm, 1912. Reprinted by permission from the Geo- 

 logical Magazine, London, Decade V, vol. 8, No. 563, pp. 217-225, May, 1911. 



* The English translation has been revised by Prof. Nathorst, and references added. 



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