THE STORY OF 111K EARTH. 



formation arc a portion oi a natural history 

 province, which has been preserved in the condi- 

 tion in which it existed on the earth's surface at 

 that particular epoch of time. 



If we suppose land and sea at the present 

 day to be occupied over their areas with natural 

 history provinces of life, in the manner in which 

 they have been marked out by naturalists, such 

 provinces are manifestly the survival of the life 

 which has existed in the several periods of the 

 geological record. They have reached their 



sent positions in consequence of the ideolog- 

 ical circumstances of rock folding m the earth's 



St which have given the earth's surface its 

 present form. This truth is the only explanation 



of the succession of life in the past ages of the 

 earth's history. It is impossible to imagine any 

 Change in Life between the oldest deposit known 

 and the bed which succeeded it, unless the life 

 Was already different in an adjacent area of the 

 in, SO that a new natural history province 



could be superimposed upon that which had pre- 

 viously Occupied the ground. The fossils of the 

 i al formations arc therefore tin Is ^i 



the 5U( i (--ion of the natural history province 



OH the earth. Kaeh province has been formed 



al chanf They have succeeded 



her like the movements of chess-men upon 



the same square of the chess-board. In this pro- 



s many of the old life provin< broken 



Up, and their constituent animals and plants S 

 1 and intermixed with others, almost be\ 



- ich survivals have not been a< < Min- 

 ded, h<< i ithout the earth losing many 



w ith w Inch the geol 



