CLOSE OF POST-PLIOCENE ADVENI OF MAN. 289 



time of the Pliocene. In these circumstances the 

 loftier hills might still reach the limits of perpetual 

 snow, but their glaciers would no longer descend to 

 the sea. What are now the beds of shallow seas 

 would be vast wooded plains, drained by magnificent 

 rivers, whose main courses are now submerged, and 

 only their branches remain as separate and distinct 

 streams, The cold but equable climate of the Post- 

 pliocene would now be exchanged for warm summers, 

 alternating with sharp winters, whose severity would 

 be mitigated by the dense forest covering, which 

 would also contribute to the due supply of moisture, 

 preventing the surface from being burnt into arid 

 plains. 



It seems not improbable that it was when the 

 continents had attained to their greatest extension 

 and when animal and vegetable life had again over- 

 spread the new land to its utmost limits, that man 

 was introduced on the eastern continent, and with 

 him several mammalian species, not known in the 

 Pliocene period, and some of which, as the sheep, 

 the goat, the ox, and the dog, have ever since been 

 his companions and humble allies. These, at least 

 in the west of Europe, were the " Palaeolithic " men, 

 the makers of the oldest flint implements ; and armed 

 with these, they had to assert the mastery of man 

 over broader lands than we now possess, and over 

 many species of great animals now extinct. In thus 

 writing, I assume the accuracy of the inferences from 

 the occurrence of worked stones with the bones of 



