Travels of a Naturalist in the Alps. 299 
This granite forms the most elevated portions of the Bernese Alps, 
and generally reposes upon the lias, though in some instances where 
this basis is wanting, it rests upon the Alpine limestone, or even on 
primitive granite. The name high granite (hochgranit) is given by 
Hover in allusion to its forming the summits of the mountains. As 
represented in the views contained in the work, it sometimes offers a 
strong resemblance in the abruptness of its elevations to trap forma- 
tions ; although it is on the whole, more prone to form needle shaped 
summits than the latter rock. ‘The author also calls it halfgranite, 
(halbgranit,) probably owing to the differences in internal structure 
between it and primitive granite. Some of its peculiarities are the 
following: It is very liable to decomposition, and particularly so, 
near the summits of the peaks, where masses readily separate into 
uregularly shaped fragments, which are stained red or black on the 
outside. Even the entire surface in some places is red from oxide of 
iron, (whence the name Rotthal*,) or black from the oxide of man- 
ganese. It is tolerably fine grained: and the ingredients are in gen- 
eral uniformly distributed, with the exception of the mica, which is 
sometimes collected into balls by itself. The quartz occasionally 
preponderates, and in some cases hornblende is substituted for mica 
or is superadded to it. 
The mode of occurrence observed by the fossils is the same 
throughout the Bernese Alps as has been observed in the Jura. 
They appear plentifully, only when the formation approaches its 
state of transition, where the lime begins to be replaced by alumina 
and silica. If however, they do occur in more homogeneous strata, 
that is, in the leading formations themselves, they are principally con- 
fined to the lowest and to the highest layers, near the commence- 
ment and the termination of the formation. ‘Terebratulites and a 
few other bivalves appear to form an exception to this law, these 
fossils enjoying a wider distribution. Another law relating to organ- 
ic remains is that their number is, in general, in an inverse order com- 
pared with the thickness of the formations. This is quite generally 
the case throughout the Alps. ‘The white Jura limestone, wherever 
found in considerable thickness as on the Balm near Soleure, affords 
no vestige of fossil remains, even when examined from the bottom 
quite to the top. It was partly on this account that it was errone- 
ously regarded as the oldest formation of the chain. Yet when this 
* Red Valley. 
ES 
