Page:Geological Evidences of the Antiquity of Man.djvu/335

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CHAP. XV.
BY THE EROSIVE ACTION OF GLACIERS.
315

the old littoral deposit. The great age of the lignite is partly indicated by the bones of Elephas antiquus found in it.

I visited Utznach in company with M. Escher von der Linth in 1857, and during the same year examined the lignite of Dürnten, many miles further down on the right bank of the lake, in company with Professor Heer and Mr. Marcou. The beds there are of the same age and within a few feet of the same height above the level of the lake. They might easily have been overlooked or confounded with the general glacial drift of the neighbourhood, had not the bed of lignite, which is from five to twelve feet thick, been worked for fuel, during which operation many organic remains came to light. Among these are the teeth of Elephas antiquus, determined by Dr. Falconer, and Rhinoceros leptorhinus? (R. megarhinus Christol), the wild bull and red deer (Bos primigenius Boj., and Cervus Elaphus L.), the last two determined by Professor Rütemeyer. In the same beds I found many freshwater shells of the genera Paludina, Limnea, &c., all of living species. The plants named by Professor Heer are also recent, and agree singularly with those of the Cromer buried forest, before described (p. 214).

Among them are the Scotch and spruce firs, Pinus sylvestris and Pinus Abies, and the buckbean, or Menyanthes trifoliata, &c., besides the common birch and other European plants.

Overlying this lignite are, first, as at Utznach, stratified gravel, not of glacial origin, about thirty feet thick; and, secondly, highest of all, huge angular erratic blocks, clearly indicating the presence of a great glacier, posterior in date to all the organic remains above enumerated.

If any one of the existing Swiss lakes were now lowered by deepening its outlet, or by raising the higher portion of it relatively to the lower, we should see similar deltas of comparatively modern date exposed to view, some of them with