Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/714

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W. BOYD DAWKINS ON THE MAMMAL-FAUNA

more from the series of normal human fibulæ than from the series of those of Bears. At all events the obscure fragment in question seems to me altogether insufficient to base any theory as to "Pre-" or "Interglacial Man," both in itself and in the conditions of its discovery. Prof. Busk, whose absence through indisposition this evening I regret, has requested me to say on his part that he "should not himself be inclined to rest or to base the existence of Preglacial Man on a fragment of bone like that, about which it is impossible that some doubt should not exist."

Nor am I aware of any other cave which offers proof of the presence of Man in this country before or during the Glacial period. Fixing my eyes upon the Pleistocene fauna only, I find that that portion of it to which Man belongs (the Arctic division) arrived in Britain before the deposit of the Boulder-clays, and lived here afterwards, and that therefore there are a priori grounds for the belief that Man also arrived at the same time. Proof of this, however, is wanting, unless the Lower Brick-earths of the Thames valley with Rhinoceros megarhinus be taken to be Preglacial, in which the discovery of a flint flake by the Rev. O. Fisher (Proceed. West Lond. Scient. Assoc. Sept. 1876) and myself in 1872 has been recently confirmed by that of a second by Mr. R. W. Cheadle.

In all probability, while the Pleistocene climate was being lowered to such a degree as to allow of the invasion of Europe by the Arctic animals Man came in; and as the climate became so severe as to allow of large tracts of ground in the north being covered with an ice-sheet, and the higher grounds of Central and Southern Europe with glaciers, Man and the animals were pushed down further to the south. When the climate, after various oscillations, grew warmer, they found their way again northwards and over the glaciated areas. On this view Man would be Preglacial, Glacial, and Postglacial in Europe, and it would be impossible to arrive at the age of any given accumulation of his remains either in the caves or river-valleys, apart from physical evidence in each case,—such evidence, for example, as that recorded by Lyell, Prestwich, Evans, Wyatt, and others regarding the fluviatile strata with Palæolithic implements at Bedford, Hoxne, and in the valley of the Thames, which are proved to be newer than the Boulder-clay of their respective districts, and to be therefore "Postglacial" in the sense of being after the minimum temperature was reached, of which that Boulder-clay is the sign[1]. I am unable to see that we gain any thing by the term "Interglacial," which Mr. James Geikie proposes not merely for these Palæolithic gravels but for all those in France as far south as the Pyrenees, without proving that any one of them is covered by a Glacial deposit.

C. The Palæolithic Man of Creswell of late Pleistocene Age.

It seems to me that glaciers and icebergs and their work, however

  1. The Palæolithic gravels of Hoxne, Bedford, and Teddington are considered by Mr. Evans later than the Upper Boulder-clay of Searles Wood (Presidential Address, Quart. Journ. Geol. Soc. 1875. p. lxxiv).