OP CREATION. 



265 



THE THIRD, OR MODERN EPOCH. 



CHAPTER XII. 



THE INTRODUCTION OF LAND ANIMALS AND THE COMMENCEMENT OF 

 THE TERTIARY PERIOD IN WESTERN EUROPE. 



THE close of the secondary period was succeeded 

 by a general disruption of the various beds that had 

 been deposited in those parts of the earth to which 

 we now have access, and by changes and modifica- 

 tions so considerable as to alter the whole face of 

 nature. It would appear, also, that a long period of 

 time elapsed before newer beds were thrown down, 

 since the chalky mud not only had time to harden 

 into chalk, but the surface of the chalk itself was 

 much rubbed and worn. 



So completely and absolutely is the line of demar- 

 cation drawn between the secondary and newer de- 

 posits in parts of the world where these beds have 

 been recognised in actual contact, that it had become 

 a common notion among Geologists, to assume the 

 destruction of all natural relations between them, con- 

 cluding that not one single species of animal or vege- 

 table connected the two periods, and lived through 

 the intervening disturbances. Although this view 

 certainly requires modification in points of detail, it 



