Periods 



Strata 



Organic History 



Terrace 



Champlain 



Man, Ass, Dog 



Bison, Stag, Beaver 

 Equus, Elephant, Hog 

 Racoon, Wolf, <fcc. 



During the Tertiary a further elevation and denudation of Utah and Rocky Mountain region, and 

 further sinking of Pacific Ocean, both coming to the present time. Great sheets of lava flowed 

 from the Sierras, covering 150,000 square miles, some places 4,000 feet thick, at the end of the 



Tertiary and during Pliocene. 



Pliocene 



Miocene 



Eocene 



Pliohippus, Oreodon 



Pithecus Semnopithecus, 

 Phoca (Seal) 



Protohippus, Hipparion 



Great Lava Flow. Forma- 

 tion of Pacific Coast Chain 



All Orders of Insects 

 Monkeys, Rhinoceros 

 Hippopotamus 

 Mesohippus, Tiger 

 Amphistegina replaces 



Nummelites 



Placental Mammals, Tapir 



Lemur, Marmosets, Ele- 

 phant and Mammoth-like 

 Animals, Bear, Camel 



Cetaceans 



Eohippus, the First Horse 

 Snakes Oak, Fig, Palm, &c. 

 Bats, Opossums 

 Nummelites (Rhizopods) 



Elevation of the Rocky and Wahsatch Mountains above water. Elevation of the Mississippi Valley 

 ibolishment of the internal sea of North America, and formation of lakes in the West. No species 



have surv 



Ived this age of oscillation. Unconformity in Europe. Time '(3,000 x5,000) , 15^00*0,000 years. 



Cretaceous 



i . I. , 1 ,_ L 



T^ I'. I '. i- 



End of Ammonitidse 

 Wading Birds with Teeth 



Teliost Fishes, Ganoids, ho- 

 mocercal 



Angiosperms and Endogens 

 begin 



Elevation of Sierra and Cascade Ranges probably simultaneous with the formation of the 

 Cretaceous period. Sinking of the bed of the Pacific. 



Jurassic 



Triassic 



More Marsupials 



More Insects 



Great, Marine, Land and 



Flying Raurians 

 Squalodont Sliarks, Ptero- 

 dactylans, Belemnites, Am- 

 monites , More Marsupials. 

 First Mammal, a Marsupial 



Ceratodus 



Bird-like Amphibians 

 Beaked Saurians, Lacertians 

 Ceratites (Ammonitida) 

 i Cycads 



FIGURE 71 



