162 



THE CLASSIFICATION OF PLANTS 



General Table of Geologic Time Divisions 



Cenozoic 

 (Tertiary) . 



Mesozoic. 



Paleozoic . 



Pbotbhozoic. 



Archeozoic . 



Present — All phyla including highest Flow- 

 ering Plants. 



Pleistocene — Nearly as at present. 



Pliocene 1 



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. 



