Scymnognathus angusticeps Broom. This is one of the South African forms closely 

 allied to the better known Russian Inostrancevia alexandri 



canines and cusped molars, the cusps being almost exactly like those of the 

 carnivorous mammals. 



A couple of months ago I discovered that in the Cynodonts the incisors, 

 canines and premolars are preceded by an earlier set exactly as in ourselves. 

 It would probably be inappropriate to call them milk teeth as it is very 

 unlikely that the Cynodonts provided their young with milk, but there can 

 be no doubt that the young had a first temporary set of front teeth like most 

 mammals. 



Besides solving the question of the origin of the mammals, the Karroo 

 fossil beds have thrown some light on the origin of birds. There has been 

 considerable discussion as to whether birds were derived from flying bat-like 

 reptiles called pterodactyls or from the dinosaurs. Some have even gone 

 so far as to derive the flying birds from the pterodactyls and the running 

 birds such as the ostrich from the dinosaurs. Dr. Lucas is one of those who 

 favors a double origin for the birds. Professor Osborn some years ago 

 argued in favor of the birds and dinosaurs having come from a common 

 ancestor in Permian times. A few years ago I maintained, as the result of my 

 studies on the development of the ostrich, that the ancestor of the bird 

 though not a dinosaur was nearly a dinosaur, and that the bird and the carni- 

 vorous dinosaur were derived from a group of primitive dinosaur-like reptiles 

 that were capable of running on their hind legs. A recent discovery in 

 South Africa reveals just such a type as we required for the common ancestry 

 of the birds and the dinosaurs and this form is also not far removed from 

 the ancestor of the pterodactyl. The birds, pterodactyls, and carnivorous 

 dinosaurs are all probably sprung from a small reptile such as the one 

 recently discovered in South Africa and named by me Euparkeria. 



Another interesting fact that seems to be brought out by our study of the 



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