88 A. BLYTT. [No. i. 



and Western North America the signs of glaciation are much 

 less prominent. 



The warm climate which prevailed in arctic and northern- 

 temperate regions, during a great part of the Tertiary period, 

 appears, according to the present state of our knowledge, to have 

 been more pronounced in the lands of the North Atlantic, than 

 in those bordering the Northern Pacific. 



Nathorst 1 has arranged the Tertiary floras of the higher 

 latitudes, according to the warmth, that they seem to indicate. 

 If we begin with the floras demanding less, and finish with those 

 demanding more warmth, we get the following order: Lena, New 

 Siberian Islands, Kamtschatka, the Amur district, Saghalien, 

 Spitzbergen, Grinnell Land, Buchtorma in the Altai, Mandchuria 

 (two localities), Northern and Middle Japan, the Khirgise-Steppes, 

 Alaska, Mackenzie, Greenland, Iceland, the Tertiary flora of the 

 Baltic and finally the numerous other European localities. From 

 this we see, that during' the Ice Age much more ice accumulated 

 in the North Atlantic quarter, whereas in Tertiary times the 

 warmth was much greater in this part than in the Pacific. 2 



As a possible argument to explain the diversity of climate 

 in Tertiary times in the different parts of the Northern re- 

 gions, Nathorst points to a displacement of the poles. He 

 says, that astronomers have nothing to oppose to this sup- 

 position, if it is considered necessary by geologists. But it 

 should be kept in mind, that although astronomers hold changes 

 of the terrestrial axis to be possible, still there are no astronomi- 

 cal reasons for believing that the pole was situated in Ter- 

 tiary times at the point proposed by Nathorst. And it appears 

 to me, that the geological facts named may perhaps be intelli- 

 gible without the hypothesis of a displacement of the poles. 



Nathorst places the hypothetical Tertiary North Pole in 1* 

 700 and long. 120° E. Gr. But this is the situation of the present 



