136 Yamasaki— Glaciation of Japan Mountains. 



question as yet. The correlation of that period with the 

 ice age of Europe and America is too difficult with our 

 present knowledge. We have not yet found any glacial 

 or glacio-fluviatile strata of diluvial age of undoubted 

 extension. Most of the Tertiary and post-Tertiary 

 strata that have been studied to date consist of marine or 

 brackish water formations, and our paleontologists are 

 eagerly endeavoring to determine the climatic conditions 

 of that epoch with especial reference to their fossil 

 faunas. Their opinions are as yet in disagreement. 

 According to Prof. Yokoyama of Tokyo University, who 

 has studied especially the formations of Tertiary and 

 later ages in the approaches of the Bay of Tokyo, the 

 climate of Middle Japan in the Pliocene was colder and 

 then became warmer in the diluvium than at present. So 

 he denied the evidence of an ice age in our diluvium. On 

 the other hand Professor Yabe, of the University of 

 Sendai, holds that at the end of the Tertiary the climate of 

 Japan became gradually colder and reached the minimum 

 temperature in the ice age, after which it became somewhat 

 warmer but again colder until it attained the temperature 

 of the present. 



Summing up briefly what I have mentioned here, the 

 lofty mountains in Middle Japan in 36° north latitude 

 were once covered by permanent snow and bore glaciers. 

 Their existence is clearly proved only by the character- 

 istic cirque topography with the corroborating evidence 

 of moraines and striae. The floor of many cirques are 

 nearly at a uniform elevation, 2,550 meters, which marks 

 the former snow line. The glaciers were hanging glaciers 

 and not of great extent and were located near the summits 

 of the ridges. No glacial or glacio-fluviatile deposits 

 have been discovered as yet that would allow of exact 

 determination of the date of the glaciation. In short, 

 the glaciated area of Japan is limited to a small district of 

 high elevation, in great contrast to the vast extent of the 

 glaciated areas of America and Europe. The lack of 

 traces of glaciation in eastern Asia, even in high latitudes, 

 will also deserve further research. How and when did 

 the ice age occur in our country! How is it related to that 

 of other regions? Other equally important subjects for 

 investigation are the direct cause of the change of climate, 

 and its influences on topography and the distribution of 



