190 BRITISH AND EUROPEAN FOSSIL ELEPHANTS. 



establishment of species, in other European countries, upon 

 less perfect materials, involving, in numerous instances, 

 superfluous synonyms. As we move northwards towards the 

 Alps, the same association of mammals is presented in the 

 Sub-Apennine Pliocene alluvium of the Valley of the Po and 

 its affluents, with this difference, that in various parts of the 

 great plain of Piedmont and Lombardy, between the Alps 

 and the left bank of the Po, there is an intrusion of erratic 

 block phenomena, which has been referred to the transporting 

 agency of ancient glaciers, extending low down on the 

 southern side of the Alps. But, so far as I am aware, there 

 is no intercalation of the characteristic forms of the glacial 

 fauna above enumerated. 



When we cross the Alps and descend upon the valley of 

 the Rhine, corresponding Pliocene alluvium is encountered 

 in certain parts of Switzerland, containing remains of at least 

 one of the characteristic fossil Elephants of Italy. This 

 stratified alluvium is overlaid by a mass of erratic drift of a 

 different age, the mammalian fossil remains when met with 

 being also different. Lower down the valley, from Basle to 

 Mayence, stretching on as far as Bonn, and running up the 

 valleys of the Neckar and the Main, is the widespread Post- 

 Pliocene fluviatile deposits of the Lehm, containing the re- 

 mains of the true Mammoth, the Siberian Rhinoceros, and 

 other characteristic forms of the glacial period. In the 

 plains of Northern Germany, a corresponding association of 

 fossil mammalia occurs in the northern Drift. Sir Charles 

 Lyell has lately directed special attention to the case of the 

 Hill of Kreuzberg, in the suburbs of Berlin, where remains 

 of the Musk Ox have been found embedded in the Drift 

 along with the Mammoth, the Siberian Rhinoceros, and 

 species of Horse, Deer, and Ox. On the plains north of the 

 Alps, the mammalia of the Drift fauna are presented to us 

 without the complication of the Pliocene period ; while on 

 the southern side, in Italy, the Pliocene mammalian fauna 

 is exhibited free from the complication of the Drift period. 



On crossing the Channel to England, the phenomena, so 

 simple elsewhere, are presented under conditions of infinitely 

 greater complexity. On the Norfolk and Suffolk coasts, de- 

 posits of unquestionable Pliocene age are seen in the Crag 

 and Lignite, or submerged Forest-bed. They contain the 

 same association of mammalian species as is met with in the 

 Sub-Apennine Pliocenes of the Valleys of the Arno and of the 

 Po. But these British Pliocenes are overlaid by enormous 

 beds of boulder-clay and superficial gravels, containing 

 mammalian remains of a much later period. The principal 

 sections exposed along the coast are subject to the wasteful 





