328 JAMES GEIKIE 



Subsequently a large valley-glacier entered the fiord, filling it 

 up, and ploughing out preexisting marine deposits. By this 

 time, however, the climate had become arctic, as is proved by 

 the character of the fauna in the contemporaneous undisturbed 

 shelly clays of the lOO-feet terraces and beaches. 



Such, stated as shortly as may be, are the main facts that 

 led me to conclude that our lOO-feet beach and the contem- 

 poraneous morainic accumulations indicate a distinct stage of 

 the Glacial Period. There was clear proof that a readvance of 

 active glaciers had taken place after the ice-sheet of the upper 

 bowlder clay had vanished from our low grounds, and from the 

 lower reaches at least of our mountain valleys. But, as I 

 remarked in my former communication to this Journal, it was 

 not quite so evident that the readvance in question had been 

 preceded by a definite and prolonged interglacial epoch. The 

 only evidence of preceding relatively genial conditions are the 

 shells which the Loch Lomond glacier took up from the old sea 

 floor and included in its moraines. 



It was with these facts and inferences in view that I 

 approached the examination of the Upper Diluvium of North 

 Germany. Perhaps it may be objected that I had no right to 

 expect that the glacial succession in Britain should correspond 

 with that of the Continent, and, if we descend to details of 

 minor importance, that is no doubt true enough. But so far as 

 the chief stages of glacial accumulation are concerned, these 

 must have followed in the same order throughout Europe. I do 

 not suppose, for example, that any geologist will doubt that the 

 epoch of maximum glaciation was one in Britain and the Conti- 

 nent, and the same must be true of other well-marked divisions 

 of the glacial system. I think, therefore, that I was justified 

 in my expectation that the Upper Diluvium of Germany would 

 prove no exception to the rule. If the valley-moraines of the 

 British mountains, which I formerly took to-be the degenerate 

 relics of our minor ice-sheet, mark in reality a recrudescence 

 of glacial conditions, it was not improbable that the German 

 Upper Diluvium would have a similar tale to tell. 



