66 



COPE 



In all of the suborders of the Permian of South Africa 

 where the parts are known, the obturator foramen and the 

 coracoid bone are small. 



Fig. 20. — Lystrosaurus frontosus Cope ; an Anomodont from South Africa, one- 

 third natural size. 



The Plesiosaueia embraces the following families : 

 Plesiosauridse, Nothosauridse, and Lariosauridse. The last 

 two families are only known from the Triassic of Europe. 

 The Plesiosauridse range from the Jurassic to the Cretacic, 



