572 MR. R. LYDEKKER ON REMAINS [NoV. 19, 



3. On Associated Remains of a Theriodont Reptile from the 

 Karoo System of the Cape. By R. Lydekker, B.A., 

 F.G.S., F.Z.S. 



[Eeceived September 19, 1889.] 

 (Plates LIV. & LV.) 



The remains of Anomodont Reptiles from the great Karoo system 

 of the Cape Colony are so rarely found in associated sets that every 

 instance of such association is of especial interest and importance, and 

 I accordingly bring to the notice of the Society a series of associated, 

 although imperfect, bones, presented in 1884 to the British Museum 

 by Mr. C. S. Orpen, of Smitlifield in tlie Orange Free State. 



These specimens (Brit. Mus. No. R. 533) were obtained from the 

 Karoo system of the Rouxville District, Orange Free State, and 

 probably from the Beaufort stage, although I cannot be certain on 

 the latter point. The bones retain portions of a brick-red ferruginous 

 matrix, which is frequently very closely adherent to them, and with 

 the colour of which they are much impregnated. This matrix so 

 closely resembles that in which the reptilian bones are found in the 

 JMaleri stage of the Gondwana system of Central India, that if the 

 specimens had beeu shown to me without any clue to their locality 

 I should have said that the}^ were probably of Indian origin. The 

 majority of the fossils in tbe British Museum from the Beaufort beds 

 are of a blackish or brownish-grey colour ; but according to Prof. 

 A. H. Green red beds are of common occurrence on this horizon. 

 The fossils in the Museum of tbe Royal College of Surgeons from 

 the overlying Stormberg beds, catalogued by Sir R. Owen under 

 the name of Massosj)ondylus, exhibit a similar red matrix. 



The series of specimens comprises a number of more or less 

 imperfect vertebrae from the dorsal and caudal regions, and. several 

 imperfect bones of the limbs and limb-girdles. Unfortunately, 

 however, there is no trace of a tooth or any portions of the skull, — 

 a circumstance which is the more to be regretted, since the South- 

 African representatives of the Theriodont suborder of the Anomodonts 

 (to which suborder these specimens belong) have been mainly founded 

 upon the evidence of the skulls and teeth. The specimens I select 

 for description are certain of the vertebrae and an imperfect scapula 

 and humerus. 



Of the vertebrae two somewhat imperfect dorsals, cemented together 

 by matrix, are represented from the right side in Plate LIV. fig. 1, 

 on a scale of two thirds the natural size. These specimens, although 

 somewhat tlattened by pressure, exhibit the entire contour of the 

 centrum and neural spine, and also show the peculiar characters of 

 the transverse processes and the position of the zygapophyses. The 

 two latter features are, however, exhibited still more clearly by the 

 imperfect arch of a dorsal represented in fig. 2 of the same Plate. 

 The centra of the dorsal vertebrae are of considerable length, and 



