CONTENTS. 



43 



(HAT. 



I'ACE 



I. Preliminary Considerations as to the Extent and 



Sources of our Knowledge i 



II. The Beginning of Life on the Earth 21 



III. The Age of Invertebrates of the Sea 



IV. The Origin of Plant Life on the Land. .... 89 



V. The Appearance OF Vertebrate Animals n; 



VI. The First Air-breathers. . . t^7 



*j7 



VII. The Empire of the Great Reptiles .165 



V^in. The First Forests of Mcdern Type 185 



IX. The Reign of Mammals 207 



X. The ADvtNT of Man 2^1 



XL Revilw of the History of Life • • • 253 



