15 
1915-16.] Opening Address by the President. 
The lake deposits of Pianico, which are underlain by moraine matter 
of the Third Glacial Epoch and are covered by moraine of the Wurm 
Glaciation, have also yielded plant remains. The larger number still 
live in that region, but a certain proportion have a south-easterly 
distribution. 
Other examples might be quoted, such as the brown coal of Uznach, 
the plant-bearing clays of Re and Calprino; but sufficient evidence has 
been adduced to prove important climatic changes during the Third Inter- 
glacial Period. 
The Fourth or Wurmian Glaciation of the Alps is marked by prominent 
moraines strewn with boulders, which show slight surface weathering. 
Associated with these morainic ridges there are outwash gravels (lower 
terrace), which are conspicuously developed round the Alpine region. 
They consist of coarse gravels, which, like the moraines, are not much 
decomposed. The moraines and gravels of the Fourth Glaciation have no 
covering of loess — a feature which distinguishes them from the older 
glacial deposits of the Alps. 
In post-Wurmian times in the Alps, Penck and Bruckner have 
obtained evidence of minor climatic oscillations which they have termed 
stadial and interstadial stages. The end-moraines of the “ retreat stadia ” 
fall into three groups, corresponding to depressions of 900, 600, and 
300 metres below the present snowline, which have been named the 
Btihlstadium, the Geschnitzstadium, and the Daunstadium. It is probable 
that the moraines of these stages may mark periods of readvance of the 
ice, for in the case of the two younger stadia (Geschnitzstadium and Daun- 
stadium) the moraines overlie deposits of gravel. The interstadial phases 
were evidently characterised by milder conditions. According to Schreiber 
the snowline in the period following the Btihlstadium rose 100 metres 
above its present level, equivalent to a rise of 3250 feet from the preceding 
cold stage. Further, the moraine of the Daunstadium rests on calcareous 
tufa, which yields a flora indicating conditions similar to those of the 
present day. 
In North America a prominent school of interglacialists has reached 
similar conclusions regarding the characteristic features of the Ice Age. 
They maintain that the Glacial Epoch was marked by a series of ice in- 
vasions, separated by intervals of time during which the ice retreated, and, 
in some cases, disappeared over large areas under conditions resembling 
those of the present day. These interglacial periods are proved by the 
denudation of the older sheet of drift before the advance of the succeeding 
one, by the depth of decomposition of the glacial materials before the 
