a 
~ 
Paleontological Discovery. 551 
the sea, with alternations of fresh water and of land; that the 
than 30,000 new species of extinct animals and plants had now 
been described. It had been found, too, that from the oldest 
separate species still held sway, almost as completely as when 
“There are as many different species as 
Infinite Being.” But the dawn of a new era was already 
ing, and the third period of paleontology we may 
consider now at an end. 
Just twenty years ago, science had reached a point when the 
belief in « eat seat ” was undermined by well estab- , 
lished facts, slowly accumulated. The time was ripe. y 
naturalists were working at the problem, convinced that Evo- 
lution was the key to the present and the past. But how had 
Nature brought this change about? While others pondered, 
Darwin spoke the magie word —“ Natural Selection,” and a | 
new epoch in science began 
