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VII. — On a neio Beptile (Proterosuchus fergusi) from the Karoo 

 Beds of Tarkastad, South Africa.~Bj E. Broom, M.D., B.Sc, 

 C.M.Z.S. 



(Plate XIX.) 



Some years ago there was discovered in an alluvial deposit on the 

 farm of Wheatlands, in the district of Tarkastad, the badly weathered 

 skull of a moderate-sized reptile. Though the fossil was not found 

 in situ, there can be no doubt it came from the rocks in the neigh- 

 bourhood. For some time the skull has been in the possession 

 of Dr. John Fergus, of Tarkastad, but at my suggestion he has pre- 

 sented it to the South African Museum, and I am thus enabled to 

 give a description of it. 



The specimen has apparently originally consisted of the anterior 

 four-fifths of the skull embedded in a sandstone matrix, but as the 

 result of weathering practically all the facial bones have disappeared, 

 and all that remains of the external bones are portions of the maxillaries 

 bearing a number of teeth, portions of the premaxillaries, consider- 

 able portions of the lower jaws, and the impressions of a number of 

 the other facial bones. A horizontal fracture along the palate 

 reveals almost the whole of the palatal bones in a very satisfactory 

 state of preservation. 



Though the skull differs very greatly from that of any animal 

 hitherto found in the Karoo beds, it bears considerable resemblance 

 to that of Ornithosuchus tooodtcardi, found in the Triassic beds of 

 Elgin, Scotland. The South African animal, however, besides 

 having been more than twice as large, has differed from the Scots 

 form in a number of important characters. In the new form, as in 

 Ornithosuchus, the skull is very narrow in front and moderately 

 broad posteriorly. The lower jaws are of considerable size. In 

 front they are very much flattened, and on passing backwards each 

 is slightly rotated outwards, so that the upper border of the posterior 

 half is directed as much outwards as upwards. The orbits are 

 large, and in front of each is a moderately large oval antorbital 

 vacuity. 



