G. W. Bulman — Glacial Geology. 403 



the Alps. Mammalian remains are found in Swiss lignites, and are 

 of distinctly recent aspect : they are, — 



(1) Asiatic Elephant {JElephas Indieus) {E. antiqiius?). 

 TJrus [Bos p7-imigenius). 



(2) Stag [Cervus elaphus). 



(3) Cave Bear [Ursus spelceus). 

 Ehinoceros sp. {R. Merkii?). 



(1) It is somewhat difficult to decide how old a deposit may be 

 which contains this living species, as it is so seldom found fossil. 



Writing in 1868, Dr. Hugh Falconer states that, "There is no 

 good evidence of the existing Indian Elephant having as yet any- 

 where in India or in Europe been met with in the fossil state." ^ 



And according to Woodward and Sherborn (British Fossil Verte- 

 brata) it has not been found fossil in Britain. 



(2) This species is found in the ossiferous caves of Wales and 

 Gibraltar, in the Norfolk Forest-bed, in Pleistocene, Prehistoric, and 

 Historic deposits. This leaves a wide margin for the age of the beds 

 in which it occurs. 



(3) This occurs in the Forest-bed, in the Pleistocene, and in the 

 caves. Again no evidence as to age. 



On the whole such an assemblage might have occurred at any 

 period from late Pliocene to Postglacial times. And yet the general 

 aspect of such a fauna suggests a later period than one in which 

 15 or 20 per cent, of the MoUusca are extinct. 



And finally, even if the lignites are interglacial as to position, this 

 does not, as we have seen, necessarily indicate a warm interglacial 

 climate. 



In America, again, Professor Geikie finds evidence of warm inter- 

 glacial conditions : 



" Another interesting feature in the American glacial deposits is 

 the occurrence of intercalated fossiliferous beds." ^ 



According to Prof. Newberry the succession of changes indicated 

 are as follows : 



1st. A period of a great continental glacier or ice-sheet. 



2nd. The retreat of the ice, and the appearance of a vast fresh- 

 water lake (covering a large part of Ohio), in which were deposited 

 the Erie clays, etc. 



3rd. The silting-up of the lake, and the advent of a luxuriant 

 forest-growth, 



4th. The submergence of the land and the deposition from floating 

 ice of blocks and boulders. 



And the resulting succession of beds was as follows in descending 

 order : 



1. Iceberg drift. 



2. Forest bed. 



3. Erie clays. 



4. Glacial drift. 



The "Iceberg Drift" above the Forest Bed, however, does not 

 necessarily imply a return of Arctic conditions after a mild interval ; 

 it may simply represent a phase in the gradual retreat of the ice 

 when its southern extent was still greater than it is to-day. 

 1 Pal. Mems. vol. ii. p. 157. * Great Ice Age, p. 416. 



