Extin ct Mammalia . 541 



They lay in a bed of ochreous sandy clay, about one foot 

 in thickness, which reposed immediately on the blu 

 London Clay. 



On the south side of the Thames, on the Cray, a 

 tributary of the Darent, which enters the Thames at 

 Dartford Marshes, palaeolithic implements have been 

 found near Green Street Grreen ; and in other places, in 

 the valley of the Medway near Maidstone, and elsewhere 

 in Kent, worked flints have been found by Professor 

 Hughes, Mr. Whi taker, and others. 1 It is therefore 

 very clear that the bones of Elephas primigenius and 

 other mammalia, some of them extinct, occur in many 

 places associated with the works of pre-historic man. 

 As yet, however, the bones of man have never been 

 discovered along with extinct mammals in British 

 river gravels, unless we get a hint on the subject 

 from the discovery of human skulls, fifty-three feet be- 

 neath the surface, at the Car on tin stream-works, north 

 of Falmouth, 'mingled with bones of deer and other 

 animals, among wood, moss, leaves, and nuts,' and ' at 

 Pentuan human skulls are stated to have been found 

 under about forty feet of detrital accumulations, also 

 mingled with the remains of deer, oxen, hogs, and 

 whales.' 2 



There is, of course, plenty of evidence that some of 

 the alluvial deposits of the Thames and many other 

 southern rivers are altogether post-glacial, and the 

 history of these alluvia can often be traced down to 



1 For many details see ' Ancient Stone Implements,' by John 

 Evans, F.R.S., chap, xxiii. 



2 < Geological Keport on Cornwall, Devon, and West Somerset,' 

 1839, p. 407 : The Geological Observer,' 1853, p. 449. Sir H. T. 

 De la Beche. The accounts of these discoveries are scarcely suf- 

 ficiently definite for an opinion to be formed with respect to their 

 comparative antiquity. 



