10 Annals of the Sontli African Museum. 



from a Therocephalian ancestor. In some Anomodonts the foramen 

 is in the middle of the bone ; in others the bone lies in front of the 

 foramen though forming its anterior wall. In no known Anomodont 

 is the foramen as here between the parietals and the preparietal 

 away from the foramen. 



The postfrontal is unusually large. In Anomodonts it is always 

 small, and in Therocephalians it was also small where it could be 

 made out distinctly. Here it forms much of the orbital margin and 

 quite a large part of the upper cranial wall. For the most part it 

 lies between the frontal and the postorbital. Posteriorly it meets the 

 parietal. 



The parietal is about as large as the frontal. In front it meets the 

 preparietal, the frontal, the postfrontal; while laterally it is sup- 

 ported by the postorbital, which completely shuts it out from the 

 temporal fossa. Posteriorly it meets the large median interparietal, 

 and posterior-laterally the squamosal. 



The postorbital is large. It forms most of the postorbital arch, 

 and its posterior extension forms the whole of the upper margin of 

 the temporal fossa. 



The squamosal is very large and forms practically the whole of the 

 back of the temporal fossa. Its inner side articulates with the 

 interparietal and the exoccipital, and forms about 1 of the occiput. 

 The ends of the parietal and the postorbital are clasped by the upper 

 and inner part of the bone. Immediately outside the lateral 

 occipital foramen the squamosal has a vertical posterior ridge which 

 apparently delimits the occiput proper from the groove which is 

 probably the auditory groove. The lower and outer part of the 

 squamosal passes down and almost entirely conceals the quadrate. 

 The outer part of the bone curves outwards and then forwards, 

 forming most of the zygomatic arch. Much of the inner side of the 

 arch is, however, formed by the jugal. 



The interparietal is a large median bone a little broader than deep 

 It is bounded above by the parietals, laterally by the squarnosals and 

 inferioriy by the exoccipitals. 



The exoccipitals appear to form the whole of the occipital region 

 above and to the sides of the foramen magnum. There is a well- 

 developed lateral process which apparently meets the quadrate. 



The quadrate lies almost entirely in front of the descending part 

 of the squamosal, and is thus scarcely seen when viewed from 

 behind. Towards the quadrate there runs out a long process of the 

 pterygoid, but whether it reaches the quadrate is not quite clear. 

 The quadrate certainly has a short process which runs forward and 



