126 Annals of the South African Miiscum. 



protuberances, the posterior of which forms the angle ; and the 

 anterior one is close in front of the other. A little in front of the 

 anterior one is a third, much smaller, tubercle. Between the large 

 post-temporal tubercle and the upper and posterior part of the orbit 

 is an irregular double ridge near the middle of which there are four 

 tubercles of not very large size — two on the upper and two on the 

 lower portions of the ridge. There are a number of smaller 

 tubercles here and there, but they do not seem to be bilaterally 

 symmetrical. It is probable that a tubercle occurred on the 

 internasal process. As in the other species of Pareiasaurus two 

 very well developed bony processes are developed on the lower sides 

 of the mandibles. 



In view of the fact that Elginia is almost certainly closely allied 

 to Pareiasaurus, it is interesting to compare the situations of the 

 bony tubercles in the latter with the positions of the horns in the 

 former. Though all the horns in Elginia do not correspond in 

 position with the tubercles of Pareiasnrus the most important almost 

 certainly do. Thus, above each orbit in Elginia are three horns, 

 apparently occupying the same situations as the three supraorbital 

 bosses in Pareiasaurus. In the nasal region are two small horns 

 almost certainly corresponding to the two nasal tubercles in the South 

 African form. Posteriorly there are two horns in the "su.pra- 

 occipital " region in Elginia. The homologues of these are probably 

 absent in Pareiasaurus ; but the two post-temporal bosses of this 

 animal are most probably the homologues of the large posterior horn 

 and the little accessory horn in Elginia. The horn on the " supra- 

 temporal " bone is probably the homologue of one of the two 

 tubercles met with in the southern form — it is impossible to say 

 which. "While the three horns at the lower angle of the cheek in 

 Elginia are most probably homologous with the three bosses at the 

 angle of the cheek in Pareiasaurus. 



The following are some of the principal measurements of the 

 skull :— 



From a point l^etween the nasal tubercles to the back 



part of the skull in the middle line 275mm. 



Distance between the points of the nasal tubercles 65mm. 



Length from angle of cheek to top of large post- 

 temporal boss 280mm. 



Length of the lower jaw (allowing for distortion) 337mm. 



The teeth of upper jaw are almost all shown, and number 14 on 

 each side. The front teeth are much higher than long, and have all 



