CHAPTER XVII. 
Eocene period — Fresh-water formations — Central France — Map — Limagiie 
d'Auvergne — Sandstone and conglomerate — Tertiary Red marl and sandstone 
like the secondary 1 new red sandstone' — Green and white foliated marls— 
Indusial limestone — Gypseotvs marls — General arrangement and origin of the 
Travertin — Fresh-water formation of the Limagne — Puy en Velay — Analogy of 
the strata to those of Auvergne — Cantal — Resemblance of Anrillac limestone 
and its flints to onr upper chalk — Proofs of the gradual deposition of marl — 
Concluding Remarks. 
EOCENE FRESH-WATER FORMATIONS. 
We have now traced back the history of the European for- 
mations to that period when the seas and lakes were inhabited 
by a few only of the existing species of testacea, a period 
which we have designated Eocene, as indicating the dawn of the 
present state of the animate creation. But although a small 
number only of the living species of animals were then in being, 
there are ample grounds for inferring that all the great classes 
of the animal kingdom, such as they now exist, were then fully 
represented. In regard to the testacea, indeed, it is no longer 
a matter of inference, for 1400 species of this class have been 
obtained from that small number of detached Eocene deposits 
which have hitherto been examined in Europe. 
The celebrated Paris basin, the position of which was 
ointed out in the former part of this volume, (see wood-cut, 
. 16) first presents itself, and seems to claim our chief 
attention when we treat of the phenomena of this era. But 
n order more easily to explain to the student the peculiar 
ature and origin of that group, it will be desirable, first, to 
ive a brief sketch of certain deposits of Central France, which 
fiord many interesting points of analogy, both in organic 
'emains and mineral composition, and where the original cir- 
cumstances under which the strata were accumulated may 
ore easily be discerned. 
Vol. III. Q 
