266 Alhanij Unspu.in necoras. 



On the use of the term Anuniodontia. 

 By R. Broom, M.D. 



Considerable confusion is caused by the fact that the term 

 Anoinodontia is used by paheontologists in verj" different 

 senses. By Seeley, Lydekker, Andrews and Smith Woodward it 

 is used for a group which includes the Pareiasauria^ the 

 ProcolDphonia, the Dicynodonts, and the Theriodonts. By Osborn 

 and Boulenger the term is used to include only the Dicynodonts and 

 the Theriodonts, while by Cope, Baur, Case, Gadow and Broom it is 

 used as synonymous with the Dicynodontia of Huxley for those 

 reptiles which are more or less closel,y related to Dicynodoti. 



The reason for the confusion is that while the term Anomo- 

 dontia as first proposed by Owen in 1859 was held to include three 

 " families," — the Dicynodontia, the Cryplodontia and tlie GnatJio- 

 dontia — in 1861 he placed the Theriodo/its, Galesaurns and 

 Cynochairtpsa in another family, — the Gynodontia of the same 

 order. In 1876 he removed the Gynodontia fTheriodontia) and 

 the Gnafhodontia and made the order include only the Dicynodni- 

 like forms. The question thus arises whether we are to foUow 

 Owen's first view or his second. Lydekker considers that 

 "although . . . there may be some doubt whether the inclu- 

 sion of the Gynodindia (Theriodonts) in the Anomoduntia was 

 not due to an error, yet the fact that such a classification was pub- 

 lished, together with the subsequent use of the latter term in this 

 sense by later English writers, seems to justify its retention." 

 Osborn evidently considers that by including the Gynodontia 

 Owen raised the order to a superordei-. 



To understand clearly the origin and meaning of the term it 

 is necessary to look at Owen's early i)apei-s. In 181.") he gave his 

 first description of Dicynodon and stated that it was "indicative of 

 a new tribe or suborder of Saunas In summing up the affinities 

 of the genus he stated that the skull, which was all that was then 



