CLIMATE OF PLEISTOCENE PERIOD. 65 



breccias, is found at present only in a few cold and shady spots. 

 The breccia at Toga has yielded also human bones associated 

 with abundant remains of a pika or tailless hare {Lagomys 

 corsicanus), a fact which strongly favours M. Locard's view that 

 the climate of Corsica during some part of the Pleistocene Period 

 was colder and wetter. The bones of this lagomys are found at 

 a height of less than 250 feet above the sea, yet it belongs to a 

 family which is now restricted to boreal regions, or to the lofty 

 mountains of warm and temperate climates. A few marine 

 shells occur in the breccia, where they have evidently been left 

 by man. According to M. Locard, the breccia of Bonaria, near 

 Cagliari, in the south of Sardinia, in which Sig. Studiati has 

 found Lagomys sardus similarly associated with marine shells, 

 has been accumulated under precisely the same conditions as the 

 breccia of Toga. 



Thus a general review of the evidence afforded by the plants 

 and molluscs of the Pleistocene deposits strongly supports the 

 conclusions that seem forced upon us by an examination of the 

 mammalia. We have distinct proofs that the Pleistocene Period 

 was characterised by very considerable changes of climate. At 

 one time the conditions were mild and genial, at another time 

 they were very much the reverse. The hypothesis of violently- 

 contrasted summers and winters which some writers have sup- 

 ported 1 is thus seen to have no foundation in fact. Even if 

 we could suppose it possible that hippopotamuses and reindeer 

 might have wandered to and fro across the whole breadth of 



1 See Lyell's Antiquity of Man) pp. 207-209. "W. B. Dawkins : Popular 

 Science Review, 1871, p. 388 ; Quart. Journ. Geol. Soc, vol. xxv. p. 192 ; xxviii. 

 p. 410 ; Cave-hunting, p. 397. In later writings Professor Dawkins seems to 

 have lost faith, to some extent, in the theory of seasonal migrations, and to have 

 partially adopted that of secular migrations ; see especially Early Man in Britain, 

 p. 112, where, if I do not misunderstand him, he now endeavours to maintain 

 hoth views at once. For additional arguments against the view of seasonal or 

 yearly migrations, see Lubbock's Prehistoric Times, 4th ed. p. 315 ; J. Geikie, 

 Geol. Mag., vol. ix. p. 164 ; x. p. 49 ; Great Ice Age, chap, xxxviii. Professor 

 Prestwich has maintained that the ossiferous and Palaeolithic river-deposits were 

 accumulated during colder conditions than the present — see Phil. Trans., 1864, 

 p. 277, — while an opinion exactly opposite has been supported by several French 

 writers, as by M. d'Archiac (Lecons sur la Faune Quaternaire). 



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