TABLE SHOWING THE RELATIVE THICKNESS OF 

 EOCKS IN EACH GEOLOGICAL PERIOD 



Rock. 



Period. 



Life. 



CAINOZOIC 



Pliocene 



Miocene 



Eocene 



Cretaceous 



Jurassic 



Triassic 

 Permian 



DEUTOZOIC \ Carboniferous 

 Devonian 

 Silurian 



Ordovician 



PALEOZOIC 



ARCHAEAN 



Cambrian 



Algonkian 



Huronian 



Laurentian 



Man. 



Primates. 

 Flowering Plants. 

 Birds and Mammals. 



Reptiles. 

 Amphibians. 

 Gymnosperm Plants. 

 Fishes. 



Insects. 



Land Plants; Cryptogams. 



Vertebrates. 



Echinodermata. 

 Brachiopoda. 



Crustacea. 



Mollusca. 



Vermes. 



Sponges (?) 

 Protozoa (?) 



68 



