FRANCE. 
217 
This fauna, as far as it goes, might belong either to the Norwich 
Crag or to the Forest-bed ; but the absence of the Mastodon is in 
favour of its reference to the newer division. Gervus carnu-- 
torum is confined in England to the Chiilesford Beds, though 
we might expect to discover this and the other extinct forms 
in newer and newer deposits as we travel further south, beyond 
the infiuence of the extreme cold of the Glacial period. The 
correlation of the gravel at Saint-Prest with the Cromer Forest- 
bed is generally accepted. ' 
Certain lignitic deposits at Durnten and Utznach, in Switzer¬ 
land, are sometimes correlated with the Cromer Forest-bed ; but 
there is nothing in the fauna or fiora to justify this allocation, 
for the species are like those of the British Pleistocene strata. 
The most probable correlation is with some of the British inter¬ 
glacial deposits, such as those of Holderness. 
In the volcanic region of Auvergne we find various fluviatile 
deposits or tuffs undoubtedly of Pliocene age. They are, how¬ 
ever, so intricately interbedded with lava-flows that it is difiicult 
to make out the stratigraphical relations of the different masses. 
The principal locality where the mammalian remains occur is 
at Mont Perrier, a steep escarpment facing a tributary of the 
river Allier, near Issoire. Here an old Pliocene lake-bed or 
alluvium has been overflowed by lava, which has served partially 
to protect the underlying strata, though they are now eroded 
into the precipitous cliffs and slopes which surround the gently- 
inclined Plateau de Pardines. The preservation of the Pliocene 
Alluvium in Auvergne is due to a cause somewhat similar to 
that which has led to the preservation of the Cromer Forest- 
bed ; in the one case a sheet of basalt protected the soft strata, 
in the other it was a sheet of Boulder Clay. 
At Mont Perrier, which forms the southern edge of the Plateau 
de Pardines, the Pliocene deposits are wasting rapidly under the 
infiuence of the rain, and bones are often washed out. The 
section of the strata is fine, though much of it is so steep as 
to be almost inaccessible, for no footing can be obtained in these 
crumbling sands. The lower part of the section is as follows* :— 
Metkes. 
Red conglomerate, with large blocks of trachyte and basalt; 1 
forming the base of the beds which contain the celebrated [► 2 
fauna of Perrier - - - - - - J 
Shaly clays, with fish, lignite, and pyrites - - - 7 or 8 
Conglomerate of large rounded quartz-pebbles, with some \ ^ 
fragments of basalt - - - - - - J 
Lacustrine marl (Miocene). 
This section was measured in the road-cutting above the village. 
The higher deposits are more sandy. 
The fossils of Mont Perrier, consisting almost entirely of 
mammalia, are sometimes considered to represent two periods— 
* Potier, Bull. Soc. Geol. France^ ser. 3, vol. vii., p. 93^. (1879.) 
