1895.] 44y [Cope. 



-which receives the extremity of the mandible. The deflected portion of 

 th3 premaxillary forms a lobe which projects as far as the continuation of 

 the line of the inferior border of the ramus mandibuli. An open emar- 

 gination of the border separates it from the corresponding lobe of the op- 

 posite side. This may be due to accident. The mandible is narrower 

 than the muzzle at the sympl)ysis ; it is a little wider than the cranium at 

 the front of the orbit, but is narrower than tlie cranium posterior to it. 



The orbit has an oval outline, with the long axis anteroposterior, which 

 enters the length of the cranium posterior to it twice, and one and three- 

 quarters times the length anterior to it, and a little exceeds the interorbital 

 width. The latter is flat. The posterior outline of the skull forms a wide 

 open emargination. The surface of the siiuU and jaws is so much in- 

 jured in both specimens as to render it impossible to state the character of 

 the sculpture, if any existed. 



The teeth are not well preserved, although where preserved their length 

 can be determined in the limestone matrix. The elongate maxillary tooth 

 is placed exactly half way between the borders of the orbit and nostril, 

 which is posterior to its position in the P. aguti. The other maxillary 

 teeth are small in comparison with the size of the skull. The enlarged 

 anterior premaxillary teeth are not well preserved, and their size is 

 uncertain. In some other specimens of similar size with rounded cross- 

 section of muzzle, these teeth are enlarged as in P. aguti,. 



Measurements. 



MM. 



Length of cranium from line connecting posterior borders of 



quadrates 162 



Length of cranium from middle of posterior border 145 



Interorbital width 32 



Diameters of orbit \ anteroposterior 36 



( vertical 23 



Width of muzzle at posterior border of nares 29 



Depth " " " " 21 



' ' of cranium at middle of orbit 35 



Length of crown of large maxillary tooth 6 



Depth of mandible at middle of orbit 20 



Length of mandible on ramus 170 



The decurved premaxillary region and the posterior expansion of the 

 skull give this species a certain resemblance to the alligator snapping 

 tortoise, Macrochelys temminckii. 



Pantylus Cope. 

 Bulletin of the U. 8. Oeol. Survey Terrs., 1881, p. 79; Transac. Amer. 

 Philos. Soc, 1892, p. 14. 



Pantylus cokdatus Cope, I. c; I. c, PI. i, Figs. 4-4a. 

 Permian formation of Texas; two incomplete crania. 



