102 peoe. owen on a caenivorous eeptile, 



Discussion. 



The President (Mr. Evans) remarked that Prof. Owen's paper 

 was a most important and suggestive one, especially as regarded 

 the views advanced respecting the connexion between these old 

 Carnivorous reptiles and the Mammalian Carnivores. 



Prof. Seeley remarked upon the extraordinary characters pre- 

 sented by the creature described by the author, and expressed his 

 regret at the want of additional materials, which might have thrown 

 a further light upon the difficult and important questions raised in 

 the paper. He thought that if all the forms referred to the Eeptilia 

 were to be regarded as belonging to that class, the latter would be 

 rather difficult to define. The present representatives of the Eeptilia 

 are the Chelonia, Crocodilia, Lacertilia, and Ophidia ; and any forms 

 departing from these are not strictly Reptiles in the ordinary sense 

 of the term. He thought the present fossil presented some Chelonian 

 characters, but that in many Lizards we may find indications of a 

 dentition similar to that of the fossil. He considered that there 

 could be no doubt as to the connexion between Eeptiles and Mammals, 

 and that Prof. Huxley was wrong in his views as to the relation- 

 ship between Birds and Eeptiles. Every mammalian type has a 

 reptilian brain in its earliest stages. The suggestion of the forma- 

 tion of a new order seemed to him to be founded upon certain 

 points which could not be regarded as absolutely proved. 



Prof. T. Rupert Jones congratulated the Society on having been 

 the medium of publication of the magnificent series of Fossil Eeptiles 

 characteristic of South Africa. He was sure that to Prof. Owen it 

 must be a heartfelt pleasure to have been the immediate elucidator 

 of these wonderful creatures of manifold and rare structures, brought 

 out by his many years of continued labour on the collections made 

 by Bain, Orpen, Atherston, and others. Together with the illus- 

 trated descriptions of Professor Huxley, his lucid and powerful 

 expositions have made the history of these creatures known to the 

 world ; and they will prove a lasting monument of his persevering and 

 elucidative work. Prof. Jones added a few words on the geological 

 occurrence and distribution of the Dicynodont and associated Eeptiles 

 in the Karoo formation of South Africa, its lacustrine or estuarine 

 origin, its enormous thickness, wide extent, and probable age as early 

 Mesozoic. 



Prof. Duncan maintained the necessity of accepting the Eeptilian 

 type as here understood by the author, and remarked that the em- 

 bryonic forms of mammals are reptilian. The question seemed to 

 him to be one of probabilities. The old beds contain the foreshadow- 

 ings of higher forms of animals. 



Prof. Owen, in reply, stated that after thirty years of work on fossils 

 he had arrived at the conclusion that the artificial line between the 

 Palaeozoic and Mesozoic series seems to need to be raised so as to in- 

 clude the Trias. The onty fossil fish from the beds yielding the 

 fossil described appeared to be Palaeozoic. He justified the reference 

 of the fossil to the Eeptilia, and remarked that in no Eeptile does 

 the ramus of the lower jaw consist of one piece. 



