AMERICAN LABYRINTHODONTIDM 593 



Pariostegus Cope, 1875 ("Synopsis of the Vertebrata Whose Remains Have Been 

 Preserved in the Formations of North Carolina," Report of the Geological 

 Survey 0} North Carolina, Appendix, p. 32). 



Pariostegus Miall, 1875 ("On the Structure and Classification of the Labyrintho- 

 donts," Report of the British Association for the Advancement of Science, 

 1874, p. 189). 



Pariostegus Fritsch, 1879 {Fauna der Gaskohle und der Kalksteine der Perm- 

 formation Bohmens, Vol. I, p. 64). 



Pariostegus Zittel, 1890 (Handbuch der Palaeontologie, Vol. Ill, p. 488). 



Pariostegus von Huene, 1902 (Uebersicht iiber die Reptilien der Trias, p. 68). 



This genus is represented by a large part of the cranium of a 

 batrachian from the Triassic coal-measures of Chatham County, 

 North Carolina. 



Contrary to what has been found the case in most genera of 

 Stegocephalia, the maxillary appears to extend posteriorly to a free 

 termination, as in modern Salamanders, and the supratemporal 

 bone presents a very prominent, obtuse, arched margin. This 

 margin extends from the margin on each side, and is inclined toward 

 the posterior part of the cranium. There is therefore no quadrato- 

 jugal piece. 



The maxillary and mandibular pieces are slender, flat bones, 

 as in Menopoma; the form of the posterior or articular portion of 

 the latter cannot be ascertained from the specimen. The more or 

 less exposed part of the median region of the latter exhibits a succession 

 of shallow transverse notches, inclosing thirteen obtuse elevations. 

 The former resemble rudimental lateral alveoli for minute pleurodont 

 teeth. A few other similar minute ribs, and, perhaps, a minute 

 curved cone without sculpture, are the only other indications of 

 dentition. 



A pair of narrow nasals, acuminate behind, penetrate between 

 the frontals as far posteriorly as the posterior margin of the orbits. 

 The suture between these is very distinct, and entirely straight. The 

 preorbitals extend to above the orbit, and then appear to cease with 

 a transverse suture. Between these and the nasals a broad triangular 

 element enters on each side, not attaining the probable position of the 

 nostrils. Each is divided by a longitudinal groove, which is probably 

 a suture, and which would then divide the frontals from the parietals. 

 The frontal would then divide the parietals entirely from the anterior 



