III. CLASS REPTILIA 



Amniota. Allantoidea. Tetrapoda. 



Occipital condyle triple or single. Vertebrae gastro- 

 centrous. 



Ilio-sacral connexion postacetabular. 

 With lungs only ; gills absent. 



1. Sub-CLASS PEOEEPTILIA 



Temnospondylous : the three pairs Of component units of 

 the vertebrae remain separate ; amphicoelous. 

 Eryops. Permian, Texas. 

 Cricotus. Permian, Texas. 



2. Sub-CLASS PEOSAUEIA 



Amphicoelous, with intercentra, or with movable chevrons. 

 Sphenodon, the only recent genus, has no copulatory organs. 



1. Order Lepospondyli. Chorda persistent, without inter- 

 ruption. Eibs with capitulum and tuberculum. 



Hylonomus. Carboniferous, Nova Scotia. 

 Hyloplesion. Carboniferous, Bohemia. 

 Hylerpeton. Carboniferous, Nova Scotia. 

 ? Smilerpeton. Carboniferous, Nova Scotia. 



2. Order Stereospondyli. Centra of vertebrae solid. 

 With numerous intercentra and chevrons. 



Eibs without tuberculum. Humerus with entepicondylar 

 foramen. 



Numerous abdominal " rib-like " ossifications. Quadrate 

 fixed. 



Two sacral vertebrae. Upper and lower temporal arch. 

 1. Sub -order PEOTOEOSAUEI, Seeley. Protorosaurus. 

 Permian, Germany. 



Palaeohatteria. Permian, Germany. 



?Telerpeton. New Eed, Elgin Sandstone. 



? Simaedosaurus. Lower Eocene, France, Belgium. 



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