CLASSIFICATION OF THE THERIODONTTA. 



59 



It is obvious that the snout is short, high, and narrow, with no 

 trace of the square section which occurs in all the Gorgonopsids 

 described above. 



The tooth- bearing edge of the maxilla is curved and passes 

 gently into that of the premaxilla without the step of Gorgonops 

 or Scymnognathus. There is, however, a diastema between the 

 closely-set incisors and the canine. 



There are clearly 5 incisors, 1 canine, and 4 or possibly 5 molar 

 teeth. The small canine recorded by Broom immediately in front 

 of the large one does not exist on the well-preserved left side, 

 and his views seem to have been founded on a small strip of 

 tooth in this position on the right side, which is really an exposed 

 portion of the lower canine. The maxilla is short and deep. 



Text-figure 17. 



Lycosaurus partialis Owen. Type-skull. 



Reconstruction of the right lateral aspect, X |. The parts represented in 

 broken lines hypothetically restored. 



The external nostril of Lijcosaarus differs considerably from 

 that of Gorgonops. It faces 'more laterally and is much larger; 

 it is no longer overhung by so large a corner of the nasal, 

 although there is still a trace of the older structure. 



The facial part of the septomaxilla is much smaller, and the 

 foramen between that bone and the maxilla is not only smaller 

 but opens more directly outward. The septomaxilla in front of it 

 seems to be rounded and grooved. Finally, the internarial 

 process of the premaxilla is longer and stands more vertically, so 

 that the end of the snout is deeper and less rounded in side-view. 



The interorbital region is narrow, the postfrontal being a 

 narrow pointed strip," as in the skull of Arctognathus curvi- 



