286 Dr. B. Petronievics on the 
by Broom. The other sutures indicated in the figure are 
rather doubtful, the best established being 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 alisphenoid. Broom 
Fig. 3. 
Skull of 7ritylodon, underside, nat. size. , probable sutures. 
1 3 
7.’-7.5, upper incisors; pmz., premaxillary; ma., maxillary; mpl. 
maxillopalatine ; pl., palatine ; pm., premolar; 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 suture separating the frontal from the nasal would prove to be 
