E. L. Troxell — Entelodonts in Marsh Collection. 363 



the distance from the orbit to the notch is relatively great. 

 From the notch backward the bone is narrow and extends 

 almost to the glenoid cavity, but the glenoid surface is not 

 cut away to receive it. 



The temporal in its outward course from the cranium 

 forms a wall reaching to the outer extremity of the glenoid 

 cavity, above which it ends in a straight narrow vertical 

 edge ; the corner folds back very slightly and forms a de- 

 pression posteriorly. Anteriorly from this edge and the 

 border of the glenoid fossa, there extends a rather 

 straight and narrow process to fit into the notch on the 

 jugal or malar bone. The distance from the condyle to 



Fig. 2. — Archceotlieri'wm, olavus clavus (Marsh). Holotype. Cat. No. 

 12035. Palatal view. One-fifth nat. size. 



the upper side of this process is relatively small, 25 mm., 

 further indicating the slenderness of the general struc- 

 ture. 



On the anterior wall of the temporal there is no fora- 

 men as in A. eras sum, but a slight tuberosity may be seen. 



The occipital condyles are set wide apart, are long and 

 narrow themselves, and are very narrowly grooved on the 

 ends. There is no fossa above the condyle, nor any fora- 

 men, as is found in the other species. The alveolar bor- 

 der, especially at the canines, descends well below the pal- 

 ate, arching the latter. The posterior edge of the infra- 

 orbital foramen lies over the middle of P 3 and opens 

 slightly downward. The upper rim of the orbit has a 

 sharp edge and the frontals, though crushed, show a 

 smooth, deep fossa without evidence of supra-orbital fora- 

 mina. The frontals anterior are very narrow, because 



