286 



Dr. B. Petronievics on the 



by Broom. The other sutures indicated in the figure are 

 rather doubtful, the best established beinp^ that bounding the 

 maxillary from above, observed by Broom. The bone 

 between this suture and the suture bounding the parietal 

 from below I suppose to be the orbito- or aliaphenoid. Broom 



Fio;. 3. 



pmxr 



Skull of Tritylodon, underside, nat. size. , probable sutures. 



i}-i.^, upper incisors ; pmx., premaxiUaiy ; mx., maxillary ; mxpl., 

 niaxillopalatine ; jj/., palatine ; J3?«., premolar j m}-m.^, upper 

 molars. 



takes it to be a prolongation of the parietal bone, having 

 supposed that the two bones meeting in a median crest are 

 frontals *. 



* I see no serious reason why these two bones should be frontals, even 

 if the sutui-e sepai-ating the frontal £i-om the nasal would prove to be 



