212 
MIOCENE PERIOD. 
[Cll. XV, 
sition of the Miocene and older Pliocene beds. It is, however, 
ascertained, that the highly-inclined green sand, which comes 
immediately in contact with the primary rocks, is the oldest 
part of the series *. 
Molasse of S witzerland. — If we cross the Alps, and pass from 
Piedmont to Savoy, we find there, at the northern base of the 
great chain and throughout the lower country of Switzerland, a 
soft green sandstone, much resembling some of the beds of the 
basin of the Bormida, above described, and associated in a similar 
manner with marls and conglomerate. This formation is called, 
in Switzerland, 'molasse,' said to be derived from 'mol,' 'soft,' 
because the stone is easily cut in the quarry. It is of vast 
thickness, but shells have so rarely been found in it that they 
do not supply sufficient data for correctly determining its age. 
M. Studer, in his treatise on the ' molasse,' enumerates some 
fossil shells found near Lucerne, agreeing, apparently, with the 
testacea of the Subapennine hills. The correspondence in 
mineral character between the green sand of Piedmont and 
that of Switzerland can in nowise authorise us to infer identity 
of age, but merely to conclude that both have been derived 
from the degradation of similar ancient rocks. 
Until the pi ace of the ' molasse ' in the chronological series 
of tertiary formations has been more rigorously determined, the 
application of this provincial name to the tertiary groups of 
other countries must prove a source of ambiguity, and we regret 
that the term has been so vaguely employed by M. Boue. 
Styria, Vienna, Hungary, 8fc. — Of the various groups which 
have hitherto been referred to the Miocene era, none are so 
important in thickness and geographical extent as those which 
are found at the eastern extremity of the Alps, in what have 
been termed the basins of Vienna and Styria, and which spread 
thence into the plains of Hungary. The collection of shells 
formed by M. Constant Prevost, in the neighbourhood of 
* We trust that MM. Pareto, Passini, Sismonda, and La Marmora, will devote 
their attention to the relative position of the several groups of tertiary strata in 
Piedmont, by instituting a comparison between their respective organic remains. 
