Two Ncio Therocephahan licptilcs. 87 



finely serrated posterior border. Behind the fifth incisor is a small 

 pointed tooth which I regard as a sixth incisor. The maxillary 

 teeth comprise a single large canine and apparently five small 

 pointed molars. The canine is somewhat flattened behind and 

 has a finely serrated edge, but so far as preserved the anterior 

 part of the tooth is smooth and rounded. The three anterior 

 molars are fairly well preserved, and in the second and third at 

 least both the anterior and posterior edges have fine serrations. 

 The fourth molar appears to be lost and the fifth is very im- 

 perfect. 



The mandible has the dentary bone relatively rather more largely 

 developed than in Lycosuchus. A somewhat oblique section of the 

 jaw near the plane of the posterior border of the orbits shows the 

 dentary above resting on the surangular with the angular and what 

 is apparently the splenial below. 



The following are the principal measurements of the skull and 

 teeth : — 



Length of skull, snout to occipital condyle 315 mm. 



Breadth of snout above canines '. 79 



Estimated interorbital width 55 



Estimated width in temporal region 145 



Length 1st incisor-5th incisor inclusive 48 



Height of 2nd incisor 24 



Length from 5th i-front of c (upper part) 12 



Length of canine 17"6 



Length from c-front of m 1 16 



Length m T -m5 inclusive 45*3 



Length of m 2 6*5 



Pristerognathus baini, n. sp. 



This new species is founded on an imperfect snout of a small 

 Therocephahan. It was obtained many years ago by Mr. T. Bain 

 in the Western Karroo, but the exact locality is unknown. It was 

 recently presented to the South African Museum by Mr. J. M. Bain 

 together with a number of other interesting specimens collected at 

 various times by Mr. T. Bain. 



The specimen consists of the snout, broken off in the region of the 



canine teeth. It does not seem to present any character by which 



it can be distinguished generically from Pristerognathus of Seeley, 



but it is a distinct species from P. pohjodon Seeley. As in that 



i6 

 species, so in this, the dental formula is --,. 



lo 



