COI^TEl^TS, 



CHAPTER I. 



PAGK 



Frelihinabt Ideas of Geolooical Chronology and op the Classi- 

 fication or Plants 1 



CHAPTER II. 



Vegetation op the Laurentian and Early Paleozoic — Qdestions 

 AS to Alo^e 8 



CHAPTER III. 



The Brian or Devonian Forests — Origin op Petroleum— The 

 Age of Acrogens and Gyhnosperms .... 46 



CHAPTER IV. 



The Carboniferous Flora- —Culmination of the Acrogens — For- 

 mation OP Coal .... .... 110 



CHAPTER V. 

 The Flora op the Early Mesozoic — Reign of Pines and Cycads . 175 



CHAPTER VI. 



The Reign op Angiosperms in the Later Cretaceous and Early 



Tertiary or Eainozoic . 191 



2 



