BOROPEAN GLACTAYT, DEPOSITS: 257 
anted by a fauna not essentially differing from that of the pres- 
ent, but the climate may have been somewhat colder. 
2. Recrudescence of glacial conditions supervened, and great 
valley-glaciers descended from the mountains, filling up the 
fiords, and ploughing out preéxisting marine deposits. The cli- 
mate at that time was Arctic—as shown by the character of the 
fauna in the undisturbed shelly-clays. 
It seemed to me quite clear, then, that the 100-foot beach 
and the contemporaneous morainic accumulations indicated a 
distinct stage of the Glacial Period. But it was not quite so 
evident that this stage had been separated from that of the 
minor mer de glace by a well marked interglacial epoch. It 
became necessary, therefore, to consider the glacial succession 
on the Continent for the purpose of ascertaining what light that 
could throw on the problem suggested by the British deposits. 
The geologists of Scandinavia, Finland and north Germany had 
discovered the existence of certain great terminal moraines, 
which, as De Geer showed, must have been accumulated by a 
great Baltic glacier. These moraines were considered generally 
to mark a pause in the retreat of the minor mer de glace —that, 
namely, of the Polandian stage —and it struck me as not improb- 
able that in them I had the equivalents of the similar accumula- 
tions of our islands. Outside of the great moraines there could 
be no doubt about the occurrence of two bowlder-clays —those, 
namely, in the Saxonian and Polandian stages. Between the 
moraines and the shores of the Baltic, however, not only two, 
but three, or even, in some places, four bowlder-clays are known 
to occur. As we might have expected, however, the occurrence 
of two or of one only is most usual. German geologists have 
classified the drift deposits of the Baltic coast-lands in the same 
way as those of the Elbe valley —recognizing, as in that region, 
a lower and an upper Diluvium. In short, they consider the 
upper bowlder-clay of the Baltic coast-lands to be continuous 
with the upper bowlder-clay that stretches south from the great 
moraines of the Baltic ridge into the valley of the Elbe. In 
this view the lower bowlder-clay of the Baltic coast-lands is on 
