200 
SCENERY OF SWITZERLAND. 
thence to Basle a slow cutting away and widening 
of the bed. 
The celebrated quarries of Oeningen, at the west 
end of the Untersee, are in freshwater calcareous 
strata reposing on the Mollasse. Heer has described 
no less than 50 species of Vertebrates, 826 insects 
and 475 plants from these deposits. 
The valley of the Rhine below Basle, as far as 
Mayence, is a band of subsidence as explained in 
the chapter on the Jura (see ante, p. 2 5). The calm 
and yet rapid rush of the river at Basle is very im- 
pressive, carrying the freshness, and the cool clear 
waters of the mountains to animate and purify the 
plains of Germany and Holland. 
