2C)H A Jbani/ Museum Records. 



year Owen gave his well-known classification of the fossil reptiles 

 he apparently carefully avoided reference to the Theriodonts, 

 because though there manifestly was some affinity between 

 Galesauriis and D cynodon, it was impossible to fit the Theriodonts 

 into the gi-oup Anouiodotifia as he had conceived it, and to have 

 done so would have done away with the importance of the most 

 striking character of the group, the anomalous dentition. 



In 1(S61 when publishing his Pala3ntology he was under the 

 necessity of putting Galesaurus somewhere, and naturally he put 

 it near Dici/nodoH. Owen throughout his long career was singu- 

 larly careful never to make a new order if he thought an old one 

 might do, and he therefore placed Galesaurus under the Auomo- 

 dontia, just as later he placed Procolophon under the Therio- 

 donfia. It seems to me however that he merely put the Gyno- 

 f/o^i/m as a " family " of the Anomodontia for convenience, and 

 had no thought of expanding the A nomodoniia in such a way as 

 to include Galesaurus, for he still defines the Anomodontia as 

 reptiles characterised by " teeth wanting or limited to a single 

 maxillary pair " (p. 255), a definition which clearly shows that even 

 in 1861 Owen meant the J nomodontia only to include reptiles with 

 an anomalous dentition. Later on, in 1876, he put the Galesaurus- 

 like reptiles into a distinct order, the Theriodontia equivalent to 

 the Anomodontia of which latter he states that Dicynodon is 

 the typical genus. The group Theriodontia is, however, quite 

 synonymous with the earlier group Gynodontia, and there seems 

 no good reason why the name should have been changed. 



Recent]}' I have shown, that the Theriodontia of Owen are not 

 a natural order in that they include animals of at least two vei-y 

 different types. Galesaurus is a very mammal-like form with a 

 well-developed secondary palate, and if we may judge by the 

 closeh' allied Gynognatltus with two occipital condyles, a 

 rudimentary quadrate and a jaw formed almost entirely by the 

 dentary. The other so called Theriodonts ilescribed by Owen sucli 

 as Gy)iochampsa, Cynodraro, &c., are not nearly related to 

 Galesaurus, having the i)ulate formed on the Rhynchocephaliaii 

 type, having a single occipital condyle and a large number of other 

 primitive charactei-s. For this latter group I reeentl}' proi)osed the 



