Fossil Reptiles. 183 



oval, and as it approaches the alveolar margin it becomes still 

 flatter, so that the section is like the v^inged stem of a plant. The 

 part of the tooth outside of the bone shows a fair sized root por- 

 tion apparently devoid of enamel, and with the edges moderately 

 parallel, and a remarkably constructed crown. The external root 

 portion of the tooth is so flattened that in one specimen — possibly 

 a maxillary molar — it measures antero-posteriorly 8 mm., and is 

 only 2 mm. thick. In the crown the flattening is continued to an 

 even greater extent. Antero-posteriorly it seems to be about 10 

 mm., though no perfect specimen has yet been displayed, and the 

 height of the crown appears to average about 13 mm. The thickest 

 part of the crown is not more than 2 mm., and from the centre it 

 thins ofl: towards the edges. The tooth is strengthened by being 

 slightly concavo-convex. The external surface of the tooth is not 

 grooved, though slightly uneven, and there are no serrations at 

 the edges visible. The layer of enamel is very thin, about .15 mm. 



If the limb bones belong to the same animal as the jaw 

 fragments, Scapanodon must have been as large an animal as 

 Titatiosuchus, as one of the humeri measures in length 535 mm., 

 and is thus exactly the same size as the humerus referred by 

 Seeley to Titanusuchus ferox. The two humeri differ consider- 

 ably if Seeley's account is correct. 



The measurement from the front of the root of lower m^ 

 to back of lower m^" is 95 mm. In Titanosuchus ferox a similar 

 measurement made on the figure gives 136 mm. 



I have much pleasure in naming the new reptile after Mr. 

 P. H. Du Plessis, of Zeekoegat. 



