GEOLOGICAL AGES AND PERIODS. 



To be read upward by beginning at Archaean on this page and 

 ending at Recent on next page. Classes and Orders of Animals 

 survive by the dying out of old and the introduction of new 

 Species. 



°S Permian. 



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D O 



OO 



9 M 



CARBONIF- 

 EROUS OR 



Coal - meas- 

 ures. 



SUBCARBON- 

 IFEROUS. 



First known Reptiles. 



Trilobites disappear. 



Orthoeerous Cephalopods nearly extinct. 



Fishes with vertebrated tails almost extinct. 



Cephalopods of many kinds. 



First Amphibians :— Labyrinthodonts. 



Fishes were all Sharks and Ganoids. 



Lepidodendrids, Sigillarids, Calamites, Ferns and 



Conifers abound. 

 Spiders, Myriapods, Scorpions. 

 Numerous Insects:— May-flies, Locusts, Cockroaches, 



Beetles. (Some of the insects were gigantic in 



size.) 

 First land Snails. 

 Crinoids culminated. Sea-urchins. 



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1-1 x 



SrS 



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a 



Catskill. 

 Chemung. 



Hamilton. 

 Cornifer- 

 ous. 



Ferns, Lycopods, Sigillarids, Calamites and Conifers. 



Eurypterids of large size. 



Limnoids; Shrimps. 



Orthopterous and Neuropterous Insects. 



Myriapods. 



Large number of Corals. 



Fishes: — Placoderms, Dipnoans, Ganoids, Chimseroids, 



Sharks. 

 Goniatites. 

 Brachiopods probably culminated in the Devonian. 



P D 



Oriskany. 

 Lower Hel- 



Salina. 

 Niagara. 



Echinoids. 



Insects: — Orthopters and Hemipters. 



Scorpions ; 



Brachiopods and Cephalopods abundant through 



Silurian. 

 Trilobites abounded through the Silurian. 



Trenton. 



Canadian. 



Primordial. 



Fishes: — Ganoids, Placoderms, and probably Sharks. 

 Insects; Eurypterids. 



Trilobites culminated in the Lower Silurian. 



Sea-weed, the only plants found. 



Cephaloposds ; Trilobites ; Crinoids ; Star-flshes ; 



Worms; Brachiopods; Lamellibranchs; Gastropods; 



Sponges; Corals; Hydrozoans; Pteropods. 



Arch.ean. Eozoon. (Probably not a fossil.) 



