PLEISTOCENE OF EUROPE, NORTH AFRICA, AND NORTH AMERICA 377 



to leave its records in regions so remote from the Alps. Similarly, Ameri- 

 can geologists have discovered evidence in certain parts of the United 

 States of five great glacial advances, two of which are more or less confluent. 

 It is obvious that in different parts of the northern hemisphere it will be 

 easier to correlate the first and the last of these successive advances than to 

 correlate the intermediate ones. The correlations which are suggested in 

 the accompanying tables in square brackets [ ] are to be regarded, there- 

 fore, as in a large measure hypothetical. 



Germany. — In studying the four faunal periods, we may first consider 

 the divisions of the Pleistocene of northern Europe as discussed by Pohlig.^ 

 Pohlig introduces the Pleistocene with what he calls the Norfolk Interglacial 

 Stage; this implies a previous glacial stage, in Great Britain at least (see p. 

 393). In strata of this age we discover what is generally regarded as the 

 First Pleistocene Fauna and will be described as such in the present work. 

 The mammals of the First and Second Pleistocene faunas are principally 

 recorded in the warmer deposits of interglacial times, namely, the Norfolk, 

 Skanian, and Helvetian. The times of the first, of the second, and perhaps 

 of the third glacial advances have left no trace of mammalian remains in 

 Germany; in the short arctic summers the districts left free by the ice 

 were flooded by the melting of the glacial edges, and there was thus no 

 chance for either plants or animals to exist. This does not appear to be 

 true, however, of the final or fourth glacial time, namely, the Berolinian, 

 which corresponds broadly with the last glaciations elsewhere, namely, 

 with the Wlirm Glaciation of the Alps region or with the Wisconsin of 

 North America. Here it is believed that we have records of animal life, or 

 of the Third Fauna which existed during the period of advance, of maximum 

 glaciation, and of retreat. The divisions of Pohlig appear to agree with 

 those of Penck on this point, and would serve to explain the fact that pre- 

 ceding and during the last glaciation we have our first positive records of the 

 Arctic tundra and steppe types of mammals in Europe, constituting the 

 Third Pleistocene Fauna. 



Switzerland. — The most recent results in Switzerland are those presented 

 by Penck, which are shown, with some modifications, in the accompanying 

 table.2 



The Glacial Period in the Alpine Region 



This table, which was prepared under Professor Penck's direction 

 (March, 1909), brings out the two distinctive features of his theory, namely: 

 (1) of the alternation of the Second and Third faunas; (2) of the correlation 

 of the human culture stages with the interglacial periods. Both are im- 

 portant if sustained by sufficient evidence. 



1 Pohlig, H., Eiszcit und Urgesfhichte des Mciischon. Leipzig, 1907. These terms are 

 used in a different order by James Geikie (1894). See also Jour. o/GeoL, Vol. Ill, pp. 241-269. 



^ Penck, A., Das Alter des Menschengeschlechtes. Zeitschr. Ethnol., no. 3, 1908, pp. 390- 

 407. 



