NEW SPECIES OP LABYRINTHOBONTS. 293 



however, a well-marked generic distinctness in the presence of a 

 postarticular process to the mandible of the latter. The oral 

 surface of the mandible of Kliytidosteus is, moreover, characterized 

 by the absence of the parapet externally to the dental series, which 

 forms such a marked feature in the present mandible ; while, in 

 place of a band of denticles situated internalli/ to the marginal 

 teeth, Rhytidosteus has a similar band placed eocteraally to the 

 latter *. We have, therefore, decisive evidence of the generic 

 distinctness of the form under consideration from llhytidosteus. 



I have hitherto been unable to find among the larger Laby- 

 rinth odonts any description of a band of denticles situated as in 

 the figured mandible. In part of a mandible preserved in the 

 British Museum (No. E. 570, a, 6), from the reputed Permian 

 of Texas, which appears to belong to Eryops mecfacephalus of Cope, 

 there is, however, a precisely similar band of denticles. Now, as 

 I have already mentioned, Eryips agrees with the present form in 

 the absence of a postarticular process to the mandible, and also in 

 having rhachitomous vertebrae ; and since the above-mentioned 

 mandible agrees with the African one in the presence of this band 

 of denticles, and also presents no characters by which it can be 

 generically distinguished from the latter, there is a presumption 

 that the Labyrinthodont under consideration indicates either an 

 African representative of Eryops or a closely allied form. The 

 African mandible indicates, however, a somewhat smaller form than 

 the typical E. mer/acephalus ; and it also seems to differ from the 

 latter in that the anterior teeth are less enlarged in proportion to 

 the hinder ones. Again, the African intercentrum differs from the 

 corresponding element of the American form in the absence of ossi- 

 fication of the axial region ; but it does not seem to me that this 

 feature is necessaiily a generic difference. I therefore propose to 

 refer the African form provisionally to the genus Eryops. with the 

 name of E. Oweni, the mandible being taken as the type. 



In conclusion, it may be observed that the reptilian and amphibian 

 faunas of the reputed Permian of Texas and the Karoo system of 

 South Africa are both remarkable for the abundance of more or less 

 closely allied types of Anomodonts ; while the first-named fauna 

 also contains numerous forms of rhachitomous Labyrinthodonts. 

 The remains of the latter group hitherto described from the Karoo 

 system are less common ; but it is not surprising to find among them 

 a form which cannot at present be satisfactorily separated from one 

 of the American genera. A connexion between the Mesozoic faunas 

 of Africa and America is already known to us by the identification 

 of the Brazilian genus Stereosternum with Mesosmirus from the 

 Kimberley beds of the Karoo system ; and the present form adds 

 further evidence of this community of types. I have recently pub- 

 lished f the description of a species of Labyrinthodont from the 

 Karoo system, which is referred to the Australian genus Botliriceps ; 



* No mention of this band of denticles, nor of the similar denticles with 

 which the palate is covered, occin-s in Sir R. Owen's memoir. 

 t Ann. Mag. Nat. Hist. ser. G, vol. iv. p. 475 (1889). 



