THE SUBCLASS SYNAPSIDA 245 



Family CYNOSUcmDAE. ? Middle Triassic. Cynosuchus Owen, 

 South Africa. 



Family Cynognathidae. Septomaxillae within nares; molars 

 cuspidate; [posterior] mandibular bones more reduced. 



Upper Triassic. Cynognathus Seeley, Lycochampsa Broom, South 

 Africa. 



Family Diademodontidae. Upper Triassic. Diademodon Seeley, 

 Gomphognathus Seeley, Trirachodon Seeley, South Africa. ? Upper 

 Triassic Cynochampsa Owen, South Africa. 



5. Theriodontia (?) Incertae Sedis 



Upper Triassic. ? Dromotherium Emmons, North Carolina. Tri- 

 bolodon Seeley, Karoomys Broom, South Africa. 



Lower Jurassic. Tritheledon Broom, Pachygenelus Watson, South 

 Africa. 



[May be either primitive mammals or cynodonts — too imper- 

 fectly known to enable one to decide. Probably each is the type of 

 a distinct family. — R. Broom.] 



