18 Annals of the South African Museum. 



is twice as broad as deep. The nostrils are large and separated by a 

 very feeble internasal process of tbe premaxillaries. Immediately 

 behind each nostril is a distinct but small boss. With these excep- 

 tions the whole of the upper surface of the skull is characterised 

 only by the typical Pareiasaurian sculpture. Even above the orbit 

 there is only a rudimentary indication of a boss. The pineal 

 foramen is large. There are no indications of the positions of the 

 sutures of the upper cranial bones, and these could only be made 

 out by seriously damaging the specimen. The total length of the 

 skull from the snout to the middle of the occipital region is about 

 358 mm. From the middle of the snout to the back of the orbit 

 is 230 mm. 



The most noteworthy feature of the skull is the great size of 



the temporal roof. In the Pareiasaurs from the Pareiasaurus 



zone the quadrato-jugal region does not descend very greatly below 



the quadrate, and the angle of the region is almost as far back as the 



occiput. In this specimen the large quadrato-jugal portion passes 



far outwards and is turned much forwards, so that what is really its 



lower border makes an angle of about 120 to the maxillary edge. 



In this it agrees with the Russian Pareiasaurs obtained by 



Amalitsky. These Russian Pareiasaurs are probably from a higher 



zone than the South African species. They are associated with 



a large species of Dicynodon and with a number of large Thero- 



cephalians. Were such an associated fauna found in South Africa 



without Pareiasaurus, it would be referred to a zone very high in 



the Permian possibly corresponding to our Cistcceplialus zone. 



The Russian Pareiasaurs differ so much from our South African 



forms that it seems not improbable they will have to be placed 



in a different genus. In any case, the skull certainly resembles 



much more closely this South African Pareiasuclius, which is also 



probably as high as the Gistecephalus zone. 



Almost the whole of the lower half of this great lateral bony plate 

 is formed by the quadrato-jugal. At the lower angle is a huge 

 rounded boss about 45 mm. in diameter. Immediately in front 

 of this is a boss about half the size of the large one. Between 

 this and the point where the quadrato-jugal meets the jugal the 

 edge of the bone is slightly thickened and forms a prominent curve, 

 which when viewed from' the side looks like another boss. On the 

 posterior border of the quadrato-jugal are three small bosses. The 

 jugal is relatively a small bone which forms the lower border of 

 the orbit and passes backwards some distance between the quadrato- 

 jugal and the bone which is probably the postorbital. 



