GEOLOGICAL FORMATIONS. 105 
‘It is sought in vain over all the clay and sand formations 
of the northern German plains, till, in the extreme north, 
it again shows itself in Rugen, where the chalk rocks of 
Arkend and Stubbenkammer lift their heads, 
‘Again, on the western coast of France, there grow various 
insignificant-looking shore plants, species of the -Salsola 
and Salicornia, which the inhabitants use to obtain soda 
from the ashes. When we travel from thence toward the 
east, we everywhere miss these little plants, even when 
searching most carefully, and merely one or other of them 
makes its appearance in places where the soil is moistened 
by some salt spring. At last we arrive at the great steppes 
of the south-east of Russia, which in summer are covered 
with a thick crust of salt, and here these plants are found 
growing in the same abundance and luxuriance as in the 
west of France. 
‘On the northern coast of Germany the little pale 
maiden pink grows upon the arid sand downs, and is 
universally distributed over the sandy plains of northern 
Germany; but these are succeeded by the granite, clay, 
slate, and gypsum of the Hartz, the porphyry, and the 
musselkalk of Turingia, and our little pink 1s not met with 
again till we arrive on the keuper sand plains, on the 
further side of the Maine, surrounding the venerable city 
of Nuremberg. It extends. further south through. the 
Palatinate, till the musselkalk of the Swabian Alps 
again sets a limit to it, but it leaps over these and the 
whole Alpine region, and at last appears again on the sandy 
soils of Northern Italy. How is it these plants everywhere 
disdain the richest soils in their range of geographical 
distribution, and are conformed to perfectly determinate 
geognostic formations? Must not the lime, the salt, the 
sand, or rather the Silex, have a most distinct influence 
in the matter? | 
«In regard to soil science has gone astray in the most 
varied and opposite directions. So late as the commence- 
ment of the present century there were men who asserted 
that plants could themselves form all their organic and 
