1894.] Organisation, and Classification of Fossil Reptilia,. 227 



VI. " Researches on the Structure, Organisation, and Classifi- 

 cation of the Fossil Reptilia. Part IX. Section 2. On 

 the Reputed Mammals from the Karroo Formation of Cape 

 Colony." By H. G. SEELEY, F.R.S. Received January 4, 

 1894. 



(Abstract.) 



The author re-examines the remains of Theriodesmus, and contests 

 the interpretation of the carpus given by Professor Bardeleben, pro- 

 ducing specimens of South African Reptiles in which there is a 

 single bone beneath the radius, as in Theriodesmus. This character 

 is shown in a small skeleton, at present undescribed, which the 

 author obtained from Klipfontein, Fraserberg, which he regards as 

 referable to a new genus. Other evidence is produced supporting 

 the interpretation of three bones in the proximal row in the carpus, 

 in a specimen from Lady Frere. The author then compares the fore- 

 limb of Theriodesmus with that of Pareiasaurus, which was obtained 

 subsequently, and arrives at the conclusion that the types of limb 

 are too closely related to be referred to different orders of animals, 

 and therefore that Theriodesmus must be transferred from the 

 Mammalia to the Therosuchia. 



The skull described as Tritylodon longcevus is examined, and its 

 close resemblance to the skulls of new Theriodonts is pointed out. 

 The author believes that it shows evidence of possessing both pre- 

 frontal and post-frontal bones, which were situate as in Theriodonts, 

 and circumscribed the orbits in the same way ; so that, although the 

 post-frontal bones appear to have met in the median line to form a 

 crest, at the back of the frontal, there is no other character in the 

 skull by which it can be distinguished from the skull of a Theriodont. 

 It therefore appears to be reptilian, and thus would make known 

 divided roots to the molar teeth in Reptilia, and a more complicated 

 type of crown than in any Theriodont yet known. 



VII. " Researches on the Structure, Organisation, and Classifi- 

 cation of the Fossil Reptilia. Part IX. Section 3. On 

 Diademodon" By H. G. SEELEY, F.R.S. Received January 

 12, 1894. 



(Abstract.) 



The author describes fragments of jaws and teeth from Upper 

 Karroo strata at Wonderbootn and Aliwal North, collected by R. D. 

 Kannemeyer and Alfred Brown. They may possibly belong to more 



