154 Annals oj the SoiitJi African Museum. 



Nothing, unfortunately, is known of the locahty of the specimen. 



Lycosuchus mackayi, sp. nov. 



This new species is represented by an imperfect maxilla and one or 

 two other very imperfect fragments of a skull. As displayed, the maxilla 

 is split longitudinally and shows 2 large canines and a small molar. 

 There is no evidence of any other teeth. The front one of the two 

 canines is of large size and is serrated both in front and behind. The 

 second canine, which is immature and has probably not yet cut the 

 gum, is also serrated both in front and behind. The little molar is 

 too imperfect to admit of description. In its general structui-e and 

 in the number of teeth this maxillary bone agrees fairly closely with 

 that of LycosucMis vanderrieti (1), which I recently described, from 

 the Karroo beds lying to the east of Beaufort West. L. mackayi is 

 an animal at least a half larger than L. vanderrieti, as will be seen 

 from the table of comparative measurements given below, and con- 

 sidering that the type of L. mackayi is probably immature. In 

 L. vanderrieti no serrations are to be seen on the front of the second 

 canine, but as the point is lost it is impossible to say whether it may 

 not have been similar to that in L. mackayi. 



L. mackayi. L. vanderrieti. 



Length of maxilla about 165 mm. 107 mm. 



Depth of maxilla about 67 56 



Front of first canine to back of 



molar 48 39 



The specimen was sent from East London many years ago by 

 Mr. G. McKay, the discoverer of the little Endothiodont reptile 

 named by Huxley Pristerodon McKay i. As a curious instance of 

 the way in which bones of different animals are sometimes found 

 mixed together in the Karroo beds, it may be mentioned that in the 

 same piece of stone which exhibits the maxillary of Lycosuchus 

 mackayi there is seen almost alongside of it the almost complete but 

 very badly crushed skull of a medium-sized Oudenodon. 



On the Affinities of the Primitive Theriodonts. 



Though the three genera Scylacosaurus, Ictidosaurus, and 

 Scymnosaurus resemble the typical Theriodonts considerably in 

 their dentition, the structure of the palate is so strikingly different 

 that it became necessary to place them in a distinct Order or Sub- 



