146 



THE MERYCOIDODONTlMi 



in advance of the antorbital margins. They are anteriorly decurved and transversely convex. The 

 muzzle is broad. The pars facialis of the lacrimal bone is roughly diamond-shaped. The lacrimal 

 fossa; are shallow but large. The frontals are wide, flat, and unreduced, with a marked decurvature 



A.M.I38I9 



Fie. 106. — Promerycochcerus thomsoni Loomis. Skull and superior dentition. HT. Cat. No. 13819 A.M.N.H. 1/3 



nat. size. (After Loomis, 1924.) 



12948 



Fig. 107. — Promerycochoerus thomsoni Loomis. Skull and inferior dentition. 



nat. size. (After Loomis, 1924.) 



PT. Cat. No. 12948 A.M.N.H. 1/3 



above the orbits. The latter are small and subcircular. The temporal ridges unite in a plane above 

 the glenoid surfaces to form a high, thick-edged sagittal crest, not more than a fifth of the skull 

 length. The supraoccipital crest is moderately produced, and the wings are not widespread. The 

 brain case is small, and the lateral ridge is well marked. The small external auditory meatus is 

 directed upward and somewhat backward and lies above and in a vertical plane between the paroccip- 

 ital process and the occipital condyle. The basicranial axis is steep. The palate is wide, somewhat 

 vaulted, and not posteriorly notched, while the V-shaped palatonarial border is nearly midway 



