THE SUBCLASS ANAPSIDA 



217 



moderate or considerable length. Two centralia pedis are doubt- 

 fully known only in Labidosaurus. Dichocephalous ribs are known 

 only in Seymouria and Pantylus. The cleithrum is vestigial in some. 



Family Seymouriidae. Primitive, terrestrial, insectivorous rep- 

 tiles less than three feet in length. Teeth conical in a single row 



Fig. 162. Skeleton and life restoration of Cotylosaurs: A., Diasparactus. After Case. One 

 twentieth natural size. B, Seymouria. About two feet long. 



on jaws and dentaries. Cleithrum vestigial or absent. Vertebral 

 spines vestigial, the vertebrae with broad arches. 

 Seymouria Broili (? Conodectes Cope). United States. 



Family Sauravidae. Slender reptiles about one foot in length. 

 Skull and intercentra unknown. 



Eosauravus (Middle Pennsylvanian). United States. 

 Sauravus. Thevenin, France. 



Family Gymnarthridae. Small reptiles six to eight or ten inches 

 in length, insectivorous or invertebrate feeders. Teeth obtusely 



