160 Annals of the South African Museum. 



The maxillary, so far as can be judged from the remains and 

 impressions, appears to agree fairly closely with that in Ornitho- 

 siichus. In this new form, however, it is better developed pos- 

 teriorly, and passes backwards as far as the back of the orbit. It 

 bears a series of large teeth. From the extremely weathered condi- 

 tion of the bone it is difficult to be certain of the arrangement of the 

 teeth. There seem, however, to be 10 large, well-developed teeth in 

 a regular series, and between these there seems to be a series of 

 immature teeth. Then, at the base of the teeth of the first series, 

 there are indications of the tips of a series of replacing teeth. If 

 this interpretation be correct, each maxilla has probably had a series 

 of 18 or 20 teeth — mature and immature teeth alternating. The 

 immature teeth have distinct sockets, but in the old teeth the roots 

 seem to be united with the bone. 



The jugal forms the lower border of the orbit. It rests on the 

 maxilla, and in front passes forwards between the lachrymal and the 

 maxilla almost to the antorbital vacuity. 



Above the impression of the maxilla on the right side is the greater 

 part of the impression of the nasal. This has evidently been a fairly 

 large bone. 



Only a very fragmentary portion of the premaxillary remains. 



The palate, which fortunately is fairly well preserved, is of very 

 great interest. Though a modification of the Khynchocephalian 

 type, the palate differs very considerably from that of any other form 

 hitherto described. 



In front, articulating with the premaxillaries, are a pair of elon- 

 gated prevomers. (These are the bones usually referred to as 

 vomers, but which I have elsewhere shown are not homologous with 

 the mammalian vomer.) They appear to articulate with each other 

 in front, but for the greater part of their length they are not in con- 

 tact. Each prevomer is considerably expanded posteriorly, and to a 

 less degree in front, but is very slender in the middle. Along the 

 inner side of each is a row of small teeth. Behind, each gives articu- 

 lation to the pterygoid and palatine bones. 



The internal nares are very elongated openings lying between the 

 prevomers and the maxillae. Each is a little longer than the pre- 

 vomer, and its posterior part lies between the maxilla and the 

 anterior part of the palatine. 



The palatines, though a little larger than the prevomers, are much 

 smaller than in most reptilian skulls. From where each palatine 

 articulates with the maxillary a short, slender process extends for- 

 wards, upwards, and inw^ards to meet the prevomer, and forms the 



