THE MAMMALIAN REMAINS. 285 



us* that some of the bones bear the marks of flint im- 

 plements ; nay more than this, he has even satisfied himself 

 "by comparative trials on homologous portions of exist- 

 ing animals, that incisions, presenting such appearances, 

 could only be made in fresh bones, still retaining their 

 cartilage/' 



There seems, then, no more reason for supposing that the 

 bones of the extinct mammalia were washed out of earlier 

 strata into the drift gravels, than for attributing such an 

 origin to the implements themselves ; and we may, I think, 

 regard it as well established, that the mammoth and woolly- 

 haired rhinoceros, as well as the other mammalia above- 

 mentioned, co-existed with the savages who used the rude 

 " drift hatchets," at the time when the gravels of the Somme 

 were being deposited. 



The second of the three questions with which we started 

 (p. 276), may therefore be answered in the affirmative. 



Must we, then, carry man back very far into the past, or 

 may we retain our date for the origin of mankind by 

 bringing the extinct animals down to comparatively re- 

 cent times? The absence of all tradition of the elephant 

 and rhinoceros in Europe carries us back far indeed in 

 years, but a little way only, when measured by geological 

 standards, and we must therefore solve this question by 

 examining the drift gravels themselves, the materials of 

 which they are composed, and the positions which they 

 occupy, so as to determine, if possible, the conditions under 

 which they were deposited, and the lapse of time which 

 they indicate. 



In this third division of the subject I shall again follow 

 Mr. Prestwich, who has long studied the quaternary beds, and 

 has done more than any other man to render them intelligible. 



* Geological Jour. vol. xvi., p. 471. 



