r6a THE STORY OK the earth. 



CHAPTER XX. 



LOWER TERTIARY. 



THE tertiary rocks occupy the basins drained 

 by many of the rivers of Europe. And although 

 they sometimes occur far inland, and at con- 

 siderable elevations above the sea, a> m the Alps, 



Atlas, and many of the mountain chains of the 

 old world, they are necessarily among the most 

 recently elevated parts of the earth's surf a 



nally there is a possibility that one de- 

 posit extends continuously from the upper creta- 

 ceous to the lower Tertiary. The evidence of 

 this continuity in time is only found in North 

 America, in the M Laramie formation." in which 

 there are no marine fossils; but which in '!'< 

 California and British North America abounds in 

 plant remains, and yields some vertebrata which 

 favour that conclusion. It would therefore ap- 

 pear that in some parts of the earth there is no 



ik between the secondary and tertiary r< 



in time, any more than between the other r< 

 which give i of geological time. The ter- 



tiary beds, when followed m their succession from 

 the oldest to the most recent, show an in< 

 number of the Is to be still living, 



while the number of genera which are extinct 



ely smaller. The geograpl 

 distribution of the surviving life, h<>\- 5 al- 



ways different from that i>\ the fossil life, I 

 • iary floras ; the ol< 

 ental and Malayan and Australian in their 

 eeded by others which have a 

 ilogy with the existing flora of the 



