EXTINCTION OF ANIMALS. I15 



been destroyed in very recent times. But 

 these have been extinctions effected through 

 the agency of Man. What is now proved 

 is that a whole group or fauna of great 

 quadrupeds have utterly perished since Man 

 appeared. And the causes of this destruc- 

 tion seem to have been of the same kind 

 as the causes which in all former ages had 

 produced similar results — viz., great changes 

 in the climates of the globe, and great 

 movements affecting the configuration of its 

 surface. In these last circumstances lies the 

 real stress of the evidence derived from the 

 new discoveries. It is conceivable that old 

 kinds of Elephant and Rhinoceros may 

 have roamed over Northern Europe when 

 its surface and its climate were the same as 

 I 2 



