Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/511

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1872.]
DAWKINS—CLASSIFICATION OF PLEISTOCENE STRATA.
417

the South, of France, where the proximity of the Mediterranean must have caused the temperature to be higher than in the north of France and Britain.

The evidence that Kent's Hole and Brixham Cavern had, at one time, been occupied by an accumulation of cave-earth and stones, which were sealed down with a coating of stalagmite, and that this was subsequently destroyed before either was filled with the deposits which it now contains, is clear and decisive.

During the Middle Pleistocene in the Thames valley, and at Clacton, the Woolly Rhinoceros, Elephant and Mammoth, competed for the same feeding-grounds with Rhinoceros hemitœchus, R. megarhinus, Hippopotamus, and Elephas antiquus. Although all the characteristic Pliocene Cervidæ had retreated, the Reindeer had not yet invaded that area: it was occupied by the Stag, the Roe, the Irish Elk, and Cervus Browni. The whole assemblage of animals, the Musk-sheep being excepted, implies that the climate was, at this time, less severe than when the Reindeer spread over the same area in the Late Pleistocene times, and was far more numerous than the Stag. It may, indeed, be objected that the classificatory value of the Musk-sheep is quite as great as that of Rhinoceros megarhinus; but in the case of the lower Brick-earths, the evidence of the latter as to climate agrees with that of the whole assemblage of animals, while that of the former is altogether discordant.

6. The Early Pleistocene Mammalia.

The fossil mammalia must now be examined which inhabited Great Britain during the Early Pleistocene period, and before the maximum severity of glacial cold had as yet been reached. The fossil bones from the forest-bed which underlies the Boulder-clay on the shores of Norfolk and Suffolk, have for many years attracted the attention of naturalists and geologists. The magnificent collections of the Rev. John Gunn and the late Rev. S. W. King gave Dr. Falconer the means of proving that the fauna of that ancient submerged forest differed from that of any geological period which we have hitherto discussed. And the careful diagnosis of all the fossils from this horizon which I have been able to meet with, shows that it was of a very peculiar character, being closely allied to the Pliocene of the south of France and of Italy, and yet possessing species which are undoubtedly Pleistocene. The following list is necessarily very imperfect, since the fragmentary nature of the fossils renders a specific identification very hazardous; and it only includes those which I have been able to identify with any degree of certainty.

Sorex moschatus.

—— vulgaris.

Talpa europæa.

Trogontherium Cuvieri.

Castor fiber.

Ursus spelæus.

—— arvernensis.

Canis lupus.

—— vulpes.

Machærodus.

Cervus megaceros.

—— capreolus.

—— elaphus.

—— Polignacus.

—— carnutorum.

—— verticornis.

—— Sedgwickii.

Bos primigenius.

Hippopotamus major.

Sus scrofa.

Equus caballus.

Rhinoceros etruscus.

—— megarhinus.

Elephas meridionalis.

—— antiquus.

—— primigenius.