CLASSIFICATION V 



In 1905 Case published two papers (13, 14) in which he demonstrated the 

 similarity of the Diadectida to the OtocoelidcE as defined by Cope, and suggested 

 that the Diadectidce be placed with the Otocoelidce in the order Chelydosauria, leaving 

 the families Pariotichida, Elginidce, and Pareiasauridee to form the Cotylosauria. 



In 1908 Williston (65) showed that Case was not within the laws of nomen- 

 clature in making this proposition and that the name Cotylosauria must go with the 

 DiadectidcE, wherever they were placed. 



CLASSIFICATION. 



The following arrangement seems to the author to be the most advisable in the 

 present state of our knowledge of the group: 



Order Cotylosauria. 

 Suborder Diadectosauria. 

 Family Diadectidx. 

 Genus Dtadectes. 

 Bolbodon. 

 Chtlonyx. 

 Dtasparactus. 

 Desmatodon. 

 Dtadectotdes. 

 Family Bolosauridce. 

 Genus Bolosaurus. 

 Family Nothodontidee (?). 

 Genus Nothodon. 



Incertae sedis. 

 Genus Eosauravus.* 

 Bathyglyptus. 



Foreign forms. 

 Genus Sauravus* 

 Suborder Paretasaurta. 

 Family Pariotichidte. 

 Genus Partotichus. 

 Isodectes. 

 Ectocynodon (?). 



♦It is belicTcd that these two forms, fiom their lower geo- 

 logical position and primitive character may represent the most 

 primitive type of the reptilia and should perhaps be placed in 

 a separate order, but as the head is unfortunately missing in 

 both specimens our knowledge is not sufficient to warrant any 

 definite conclusion as to their position. 



Order Cotylosauria — Continued. 

 Suhovdtr P ar etas auri a — Continued. 

 Family Captorhinidte. 

 Genus Captorhinus. 

 Labtdosaurus, 

 Helodectes (J). 

 Family Seymouridee. 

 Genus Seymouria. 



Conodectes (?). 

 Stephanospondylus (?). 



Foreign forms. 

 Family Pareiasaurida. 

 Genus Paretasaurus. 

 Propappus. 

 Anthodon. 

 Elginia. 

 Phanerosaurus. 

 Sclerosaurus. 

 Suborder (?) Procolophonia. 

 Family Procolophonidee. 

 Genus Procolophon. 

 Thelegnathus. 

 Saurosternum. 

 Family Telerpetid<B. 

 Genus Telerpeton. 

 Suborder Pantylosauria. 

 Family Pantylidee. 

 Genus Pantylus. 



Attention is also called to the note at the end of the comparative tables (p. 66). 



