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SCENERY OF SWITZERLAND. 
Here and there also in the drift and the peat- 
mosses of the lowlands remains have been found of 
Alpine and Arctic species — the Arolla pine, dwarf 
birch (Betula nana), Arctic willows (Salix polaris, 
Salix retusa, and Salix reticulata), Dryas octopetela, 
Polygonum viviparum, etc. 
Moreover, we find living colonies of high Alpine 
species, the seeds of which can scarcely have been 
carried by wind, on elevated summits in the lower 
districts, and in the marshes behind ancient moraines. 
They cannot have been brought by water, because 
they occur in some districts not watered by Alpine 
streams. On the Uetliberg Prof. Heer found two 
plants which especially characterise moraines — the 
Alpine toad flax (Linaria Alpina), and a willow-herb 
(Epilobium Fleischeri). An Alpine fern (Asplenium 
septentrionale) which is said to be found nowhere 
else in the Canton of Ziirich, occurs on the Plough- 
stone of Erlenbach. There are two Swiss species of 
Rhododendron — one with the under surface of the 
leaves rusty (R. ferrugineum), the other with fringed 
leaves (R. hirsutum). The latter species prefers a 
limestone soil and lower regions, so that we should 
expect to find it prevalent on the Jura. Yet the 
rusty-leaved species alone occurs there, having prob- 
ably been brought by the ancient glacier from the 
