CONTENTS 



I 



PAGE 



The Chain of Life Traced Backward in Geological 



Time ^ 



II 



Life in the Early Cambrian '7 



III 

 Pre-Cambrian Life • • • 47 



IV 



Foundations of the Continents, and their General 



Testimony as to Life 79 



V 



Probabilities as to Laurentian Life, and Conditions 

 OF its Preservation '°7 



VI 



The History of a Discovery ^25 



VII 



The Dawn of Life '^7 



si 



