MOODIE: PERMIAN ANPHIBIA. 245 



Williston's figure (Kan. Univ. Quart., Ser. A, vol. VIII, pi. 

 XXX, fig. 1), which is reproduced here with slight changes. 

 The sharp angulation and the posterior position of the angle is 

 a specific character which serves to distinguish this species 

 from Eryops megacephalus Cope, to which the present form is 

 most nearly allied. 



The jaw (plate XLIX, fig. 1), is heavy and elongate. The 

 portion posterior to the coronoid angle is an acute triangle 

 which ends in the articular. Only a portion of the suture 

 bounding the articular can be distinguished. This is indicated 

 in the figure. The coronoid suture is evident for its entire 

 course. The suture starts from the articular suture, and run- 

 ning directly forwards turns upward just before reaching the 

 teeth, which do not occur on the coronoid. This element is a 

 thin bone superiorly but more thickened below. The sutures 

 separating the angular, surangular and dentary cannot be de- 

 termined. The angular and surangular contain, on their exter- 

 nal surface, the peculiar nodose ornamentations which help to 

 characterize the present species. 



The sculpture on these elements consists of scrobiculate 

 knobs some 5 to 7 mm. in diameter. This ornamentation ends 

 apparently at the dentary, since the tooth-bearing element, 

 which is quite large, is ornamented only with coarse elevations 

 and pits. 



The operculo-mandibular lateral line canal can be traced as a 

 depression beginning on the articular and running forward as 

 far as the bone is clearly preserved. It occurs as a shallow 

 groove interrupted by the nodose and scrobiculate sculpturing 

 of the mandibular elements. The internal surface of the man- 

 dible is not preserved in sufficient detail for description. 



Complete teeth are lacking from the mandible in its present 

 condition. Doctor Williston figured tvv^o of them as complete, 

 and it is quite probable that they have been broken off since he 

 studied the specimen, because the material is excessively 

 fragile. The hollow character holds for all of the tooth bases 

 which are preserved on the mandible. An additional portion 

 of the mandible is shown in figure 5, plate XLIX. Its char- 

 acters do not differ from those described above. 



In regard to the hollow nature of the teeth. Tomes has the 

 following explanation : "The laminse of pulp, with their several 

 systems of dentinal tubes, instead of passing out in straight 



