374 S. W. WILLISTON 



The jugal is well preserved in two specimens, completely so 

 in one, with the postfrontal process broken away in the other; 

 a third specimen shows the posterior process. It is a long, narrow 

 bone, which borders the whole lower side of the orbit. It sends 

 a short, pointed process backward to articulate below the front 

 part of the squamosal. The process which is directed upward to 

 meet the postfrontal and postorbital is broader, ending in a slender 

 projection on the front side which overlaps narrowly the post- 

 frontal in front of the postorbital. Posteriorly above it also meets 

 the lower part of the anterior expansion of the postorbital. The 

 anterior end extends nearly to the extreme front end of the orbit, 

 bordering for a long distance the upper side of the maxilla. The 

 bone forms the free margin of the arch back of the maxilla for only 

 a short distance. 



The frontals are moderately broad and rather long bones, 

 evidently flat or gently concave between the orbits. In most 

 specimens they are pressed more or less together, but, by excavat- 

 ing one of them, I have determined its precise shape. It forms the 

 orbital margin for only a short distance between the ends of the 

 postfrontal and prefrontal. The frontonasal suture is a little 

 before the front end of the prefrontal. 



The prefrontals are visible in part or wholly on four sides. 

 They are large, triangular bones, projecting outward somewhat 

 in front of the orbit. They extend back narrowly along the frontal 

 margin to within a short distance of the anterior end of the post- 

 frontals. 



The maxillae are unusually broad bones for a Permian reptile. 

 Each articulates with the nasal in front, excluding the lacrimal 

 from the nares. It is more or less complete in four cases. It 

 terminates posteriorly in an acute point a little before the hind 

 border of the orbit, and is bordered to its highest elevation by the 

 slender jugal. A small space is left between the end of the jugal 

 and the prefrontal in which there may have been a small lacrimal, 

 but this bone cannot be distinguished with certainty in any 

 specimen. 



Of the premaxillae I can say but little. In only one of the speci- 

 mens can I detect any vestige of it. In one skull, however, the 



