114 



A REVISION OF THE COTYLOSAURIA OF NORTH AMERICA 



The maxillary and premaxillary teeth are much heavier and more blunt than 

 in Captorhinus and exhibit nothing of the diversity shown in Edaphosaurus. The 

 posterior portion of the maxillary is covered, and it is impossible to say whether there 

 was more than one row of teeth or not, but it is possible that there was but one, as the 

 function of these in Captorhinus was probably taken by the patch of blunt teeth on 

 the palatines and pterygoids, as in Edaphosaurus. 



Fig. 51. — Pantylus cordatut. 



a, Restoration of upper nirfacc. After Cope. Lettering a< in previous figures. X }. 



b, Restoration of side of skull. After Cope. Lettering as in previous figures. X 4. 



c, Restoration of side of skull, according to the author's interpretation. X J. No. 4330 Am. Mus. 



d, Upper view of fragment of left lower jaw. x J. No. 4331 Am. Mus. 



The lower jaws, as shown in specimen No. 4331, were nearly flat on the lower 

 surface and the inner surface was nearly vertical, so that the two surfaces met in a 

 right angle. The patch of teeth mentioned above is arranged in seven irregular 

 rows; the anterior edge of the patch is broken away, so its anterior extent can not be 

 made out; the anterior part of the jaw, specimen 4330, has but a single row of 

 teeth; a fortunate break shows that the first was small and the second abruptly 

 larger. 



A small fragment of a lower jaw. No. 4445, was labeled by Cope Pantylus 

 tristychus. It was never described and is in all probability from an old individual 

 o{ Captorhinus. 



