284 CONTEMPORANIETY OF 



Most of these species are now extinct. Some few, as the 

 Bos primigenius and Bison priscus, have come down to historic 

 times ; the reindeer, even now, abounds in the north ; but 

 only one, the stag, still occurs wild in Western Europe. If 

 these bones, then, belonged to a period earlier than that of 

 the gravel, where, we may ask, are the remains of the ani- 

 mals which did exist at that time? Moreover, the bones, 

 though sometimes much worn and broken, are at others, and 

 even according to Mr. Prestwich, " as a general rule* either 

 not rolled at all, or are slightly so." 



Secondly, these species, and particularly the mammoth and 

 the woolly-haired rhinoceros, are the characteristic and com- 

 monest species of these beds, not only in the Valley of the 

 Somme, but in all the drift gravels of England and France ; 

 while if they belonged in reality to an earlier period, they 

 would not occur so constantly, and they would be accompanied 

 by other species characteristic of earlier times. 



Thirdly, the materials forming the drift gravels of the 

 Somme Valley have all been obtained from the present area 

 of drainage, and there are in this district no older beds, from 

 which the remains of these extinct mammalia could possibly 

 have been derived. There are, indeed, outliers of tertiary 

 strata, but the mammalian remains found in them belong to 

 other, and much older species. 



Fourthly, as regards the rhinoceros, we have the express 

 testimony of M. Baillon, that on one occasion all the bones 

 of a hind leg were found in their natural positions, at 

 Menchecourt near Abbeville, while the rest of the skeleton 

 was* found at a little distance. In this case, therefore, the 

 animal must have been entombed before the ligaments had 

 decayed away. 



Finally, as regards the same animal, M. Lartet assures 



* Phil. Trans. I.e. p. 300. 



