Theriodontia — Diadectidce and Bolosauridce. 



61 



No. 4. 

 Table-case, 

 No. 18. 

 Empedias. 



the Permian formation of North America. The preraaxillary and Gallery, 



maxillary teeth are of unequal size, as in Galesaurtts, and there 



are two tusks near the extremity of the dentary bone. In Dime- 



trodon and Naosaurtis the ne viral spines of the dorsal vertebrae 



have an extraordinary development ; the height of the spine in 



one species being more than twenty times the length of the 



centrum. Prof. Cope nonclndes that these spines formed a kind 



of elevated fin on the back, of which it is difficult to imagine 



the use. In Naosaurus there were horizontal processes on the 



spines of the vertebrae. This genus has also been recorded 



from the Permian of Bohemia (see Fig. 79, p. 59.) 



Family Diadectidj*;. — In the Diadectidj:, represented by 

 the genera Diadedes, Empedias, and Helodectes, the teeth are 

 transversely elongated, and are also divided by a median vertical 

 ridge, but both the inner and outer sides are equally low. They 

 are believed to have been herbivorous in diet. 



These genera are characteristic of the Permian of North 

 America; see Figs. 81 and 82, Empedias molaris (Cope). 



Family Bolosaurid^. — Another closely related form, re- 

 ferred to the family of Bolosaurid^, named Deuterosaurus, is 

 found in the Permian of Russia (Fig. 88). 



Fig. 82. — Lateral and palatal view of posterior 

 tooth of £mpedias mohiris (Cope) ; Permian, 

 North America. 



fiG. 83. — Lateial view of a premolar 

 of DeiUero mm ut. hiarmicas (Eich- 

 wald), from the Upper Permian of 

 Russia. 



A tooth has been obtained from the Karoo beds of South 

 Africa closely resembling in general characters the anterior 

 teeth of Eeuterosaurus. It has been made the type of the 

 genus Glaridodon. 



Sub-order 4. — Pariasauria. 



In this sub-order are placed the remains of several other 

 genera of Anomodonts. They include Pariasaiirus, Anthodon, 

 and Propappus, from the Triassic deposits of South Africa. 



Wall-case, 

 No. 9, and 

 Tatole-case, 

 No. 18. 



