162 



THE CLASSIFICATION OF PLANTS 



General Table of Geologic Time Divisions 



CENOZOIC 

 (Tertiary) . 



MESOZOIC . . 



PALEOZOIC 



PROTEROZOIC. 

 ARCHEOZOIC. . 



Present All phyla including highest Flow- 

 ering Plants. 



Pleistocene Nearly as at present- 

 Pliocene ] 



Miocene > Increase in higher Flowering 



Oligocene j Plants. 



Eocene Increase of Flowering Plants. 



Upper Cretaceous Rapid increase of lower 

 Flowering Plants. 



Lower Cretaceous (Comanche or Shastan) 

 Appearance of lower Flowering Plants. 



Jurassic Ferns, Cycads, Conifers. 



Triassic Ferns, Cycads, Conifers. 



Permian Ferns, Calamites, Lycopods, Cy- 

 cads, Conifers. 



Coal Measures, or Pennsylvanian Ferns, 

 Calamites, Lycopods, Cycads. 



Subcarboniferous, or Mississippian Ferns, 

 Calamites, Lycopods, Cycads. 



Devonian Ferns, Calamites, Lycopods, Cy- 

 cads. 



Silurian Probably some land vegetation. 



Ordovician Probably some land vegetation. 



Cambrian Apparently some higher algae. 



Keweenawan 1 Probably 



Animikean (Upper Huronian) [only simple 



Huronian J algae. 



Archean Complex Probably only very sim- 

 ple algae. 



