1894.] Organisation, and Classification of Fossil Reptilia. 225 



which are unknown in Lycosaurus. The palate of Lycosaurus civrvi- 

 mola is found and described in the type specimen. It shows a trans- 

 verse development of the palatine arch abutting against the lower 

 jaw, behind which is a long compressed sphenoidal keel flanked by 

 narrow pterygoid bones. The occipital condyles do not appear to be 

 prominently developed in Lycosaurus. The genus is regarded as the 

 type of a division of the Theriodontia, defined by having the molar 

 teeth pointed and without cusps. A snout from Tamboer, named 

 Pristerognathus polyodon, is referred to this group. It is characterised 

 by six incisor teeth in each premaxillary bone and three incisor teeth 

 in each ramus of the mandible, followed by canine teeth and small 

 molars of Lycosaurian type. 



Professor Cope's definition of the Theriodontia as distinguished 

 from the Anomodontia by characters of the post-orbital arch is re- 

 garded as unsupported by evidence. The author would limit the 

 Theriodontia to animals which conform to Sir R. Owen's original 

 definition based on the dentition (1876), and have temporal vacuities 

 and a small quadrate bone. It would then include the Lycosauria, with 

 type Lycosaurus curvimola ; the Cynodontia, with Cynognathus<cratero- 

 iiotus (n.sp.) and Thrinaxodon liorhinus as types ; and a group of 

 South African Reptiles named Gomphodontia, based upon new genera 

 GompTiognatJius and Trirachodon, which have the molar teeth with 

 flattened cuspidate crowns more or less worn with use. The palate is 

 formed on the type of Lycosaurus in these Theriodontia. 



Gorgonops is closely allied to Theriodonts in its dentition (though 

 no molar teeth are known). The skull is closed behind as in Kiste- 

 cephalus, and the temporal vacuities are roofed. It appears to show 

 a palate formed on the same plan as in Theriodontia so far as its 

 transverse development is concerned, but it has not any hard palate 

 extending above the posterior nares as in Theriodontia. It is re- 

 garded as the type of a distinct group, named Gorgonopsia. 



The Pareiasauria have the same transverse palatine arch, abutting 

 against the lower jaw, but not developed downward to the same 

 extent, as in Theriodontia. Its hard palate appears to be carried 

 back behind the teeth, so that the posterior nares are further back 

 than in the Theriodontia. It differs from the Theriodontia in the 

 slight development of the coronoid process of the lower jaw, and in 

 having the temporal vacuities roofed ; and from the Gorgonopsia in 

 having the skull open behind, and in having no canine teeth. 



The Endothiodont type is believed to show the transverse descend- 

 ing palatal arch between the rami of the mandible. Pristerodon is 

 regarded as possibly Endothiodont; and EndotTiiodon uniseries is 

 made the type of a genus Esoterodon. A small skull from Molteno 

 Pass, Cryptocynodon simus (n.sp.), is regarded as an Endothiodont 

 with imperfectly- developed canine teeth. The Endothiodontia have 



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