CONTENTS IX 



Suborder Procolophonia 220 



Family Procolophonidae 220 



[Suborder uncertain] 



Family Elginiidae 221 



Order Eunotosauria 221 



Order Testudinata or Chelonia 222 



Suborder Amphichelydia 223 



Family Proganochelydidae 223 



Pleurosternidae 223 



Baenidae 224 



Suborder Pleurodira 224 



Family Pelomedusidae 224 



Chelyidae 224 



Miolanidae 224 



Suborder Cryptodira 224 



Family Thalassemyidae 225 



Toxochelyidae 225 



Desmatochelyidae 225 



Protostegidae 225 



Cheloniidae 225 



[Dermochelyidae] 226 



Chelydridae 226 



Dermatemyidae 226 



Emydidae 226 



Testudinidae 227 



Suborder Trionychoidea 227 



Family Plastomenidae 227 



Trionychidae 227 



CHAPTER IX 



Subclass Synapsida 228 



Order Theromorpha 228 



Suborder Pelycosauria 233 



Family Sphenacodontidae 233 



Suborder Edaphosauria 233 



Family Edaphosauridae 233 



Suborder Poliosauria 233 



Family Poliosauridae 233 



Ophiacodontidae 233 



Suborder Caseasauria 233 



Family Caseidae 233 



Suborder uncertain 236 



Family Paleohatteriidae 236 



Genera incertae sedis 236 



Order Therapsida 236 



Suborder Dinocephalia 237 



Family Tapinocephalidae 238 



Deuterosauridae 239 



