274 Annals of the South African Museum. 



The premaxilla is well developed, and is not overlapped by the 

 maxilla, as in Therocephalians. It meets the nasal behind the 

 nostril, and it forms a very short internasal process. There are 

 four rounded incisors which, like the canines and molars, are, so far 

 as preserved, without any trace of serrations or cusps. The space 

 occupied by the incisors is 15 mm. The snout has been split in the 

 middle line to show the relations of the vomer, prevomer, and 

 palatine process, but it is impossible to be quite sure of all the 

 details. The vomer is a large median bone, as in all Cynodonts, and 

 it has the same relations behind the palatines and pterygoids. In 

 front it lies above the secondary palatine plate of the maxilla, and 

 passes forward to within 4 mm. of the root of the 1st incisor, where 

 it lies above an elongated triangular bony process. "Whether this 

 bony process is palatine process of the premaxilla or not is doubtful. 

 It seems to be continuous with the premaxilla, and may provisionally 

 be regarded as the palatine process. It is remarkable for having a 

 very large, apparently cavernous, space in it. I do not think the 

 space has been for the accommodation of Jacobson's organ, as its 

 walls are very irregular, and it is very near the roots of the incisors. 

 It is too far back, on the other hand, to be a cavity for the development 

 of a second tooth. Above it, and roofing it for the most part entirely, 

 is a thin bone, which is most probably the septo-maxillary. The 

 septo-maxillary is well seen in the floor of the nostril externally, and 

 this flat plate of bone is apparently the inner continuation of the 

 same bone. It is thus very doubtful whether there is any trace of 

 the prevomer left, and there is no evidence of an organ of Jacobson. 

 If this conclusion be correct, Banna would agree in this with the 

 Anomodonts and a number of mammals. 



The palate is, so far as can be seen, exactly like that of the typical 

 Cynodonts, and the structure of the posterior naves also similar. 



The basis cranii is peculiar in that there are two prominent 

 processes passing downwards and outwards from the basisphenoid, 

 and probably giving support to the inner end of the tympanic. This 

 is an arrangement differing somewhat from that of the typical 

 Cynodonts but very similar to that seen in the Anomodonts. 



The exoccipital forms a large transverse process, passing outwards 

 towards the articular region, as in other Cynodonts. Doubtless 

 above it lies the opisthotic. Near the inner end of the exoccipital is 

 a large round foramen, situated exactly as in better-known Cynodonts. 

 It seems to correspond to the large foramen behind the condyle in 

 Ornithorhynchus, and probably served for the transmission of the 

 9th, 10th, llth, and 12th nerves. The 12th nerve has in part a 



