2 5 2 SCENERY OF SWITZERLAND. 
the objection that the Glacial period is no mere local 
phenomenon, but seems to have affected the whole 
northern hemisphere. 
In considering the great Italian lakes which 
descend below the sea level, one suggestion has 
been that they are the sites of the ends of the 
ancient glaciers, and their lower ends are certainly 
encircled by gigantic moraines. We must, however, 
remember that the valley of the Po is an area of 
subsidence and a continuation of the Adriatic, now 
partially filled up and converted into land by the 
materials brought down from the Alps. Under these 
circumstances we are tempted to ask whether the 
lower lakes at least may not be the remains of the 
ancient Sea which once occupied the whole plain. 
Moreover, just as the Seals of Lake Baikal in 
Siberia carry us back to the time when that great 
sheet of fresh water was in connection with the 
Aictic Ocean, so there is in the character of the 
launa of the Italian lakes, and especially the pres- 
ence of a prawn in the Lake of Garda, some con- 
firmation of such an idea. 
However this may be, the lower ends of the 
lakes have been dammed up by glacial accumula- 
tions. 
Further evidence, however, is necessary before 
