INTRODUCTION. 
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Ostracoderms 
Palaeospondylus 
Elasmobranchs 
Ganoids 
Teleosts 
Arthrodira 
Dipnoi 
Stegocephals 
Gymnophiona 
Urodela 
Anura 
Theromorphs 
Plesiosaurs 
Chelonia 
Ichthyosaurs 
Rhynchocephals 
Dinosaurs 
Squamata 
Crocodiles 
Pterodactyls 
Birds 
Monotremes 
Marsupials 
Edentata 
Insectivores 
Chiroptera 
Rodentia 
Ungulata 
Sirenia 
Cetacea 
Carnivores 
Primates 
Table showing the geological distribution of the various groups of vertebrates. 
