Sir H. H. Howorth—The True Horizon of the Mammoth, 21 
6. Greyish clay and fine sand, containing Planorbis, Paludina, and 
Cyclas. 
7. Molasse and Nagelfluh of Tertiary age.’ 
This is a very good example, and it seems to be very conclusive. 
According to the same authors, bones of the Mammoth have been 
found by M. Miollet, in the valleys of the Jura at Neuchatel, in a 
thin stratum of diluvium gravel, composed of Jurassic and Tertiary 
pebbles, and covered by glacial débris, consisting entirely of Alpine 
rocks.’ 
Let us now turn to the famons lignites at Diirnten and at Utanach, 
near Zurich, upon which so much has been written. It has been 
often said, on the authority of Professor Heer, that the beds in 
question are intercalated between beds of drift. Heer, however, 
writes most guardedly on this subject. ‘‘In Hastern Switzerland,” 
he says, ‘‘until recently the upper erratic formation only was known 
which overlies the stratified pebble beds. At Utznach, in a section 
on the road to Gausen, now again covered up, Prof. A. Escher von 
der Linth saw quite distinctly the direct superposition of the lignite 
formation upon the Miocene beds; so that at least, at this point, 
there were no traces of erratic blocks to be seen between the 
Miocene beds and the lignites. At Dirnten also, the clays under 
the lignite formation only contained such stones as may have been 
derived from the conglomerates of the surrounding hills. The 
hypothesis of two Glacial periods does not, therefore, seem to be 
supported by the facts observed in Hastern Switzerland.” The same 
views are maintained by Sir Charles Lyell. He visited the beds at 
Utznach in company with M. Escher von der Linth, and those at 
Diirnten with Professor Heer and M. Marcou. ‘The beds in both 
places,” he says, ‘“‘are of the same age. At Utznach the lignite 
beds rest directly, but unconformably, on highly inclined, and some- 
times vertical, Miocene molasse, and are covered with gravels, and 
these again with erratic blocks,’ and he distinctly says that the 
evidence is wanting at Utznach to establish their interglacial 
character. 
In regard to the deposits at Diirnten, M. Charles Grad, who 
examined them with great care, found the underlying beds to consist 
of light-coloured clays or marls, such as occur in freshwater beds in 
lakes and marshes. These marls contain numerous rolled pebbles, 
but M. Grad says, “je n’y ai pas remarqué de stries glaciaires.” 
It would seem, therefore, that so far as the beds at Dirnten and 
Utanach are concerned, the evidence is against their being underlaid 
by any drift deposits, and confirms the British evidence. We are 
told, however, that a different conclusion must be drawn from a 
similar bed occurring at Wetzikon, near Diirnten (in which the 
plants were exactly similar to those at Diirnten, and which is 
doubtless of the same age), and that there Alpine blocks had 
been found underneath the lignite. The evidence about it, how- 
ever, is very unsatisfactory. In the first place, Heer speaks of 
1 See Bull. Soc. Geol. de France, 2nd ser. vol. vii. 1858, p. 601. 
2 Td. 602. 
