Douglass : Vertkurates from Montana Tertiary. 177 



not be too positive about there being prelachrynial vacuities, but if 

 not, there were certainly prelachrynial pits. On one side there is a 

 large circular space anterior to the orbits which has no bone and the 

 surrounding bone, in part, appears to be unbroken. 



The skull is a little longer than that of Mesoreodon chelonyx Scott. 

 The nasals are lost. The malomaxillary ridge is high, very convex, 

 extends upward as well as forward, dying out near the upper border 



Fig. i8. Poairephes pahidicolaijso. Z\^). Flint Creek beds. One half natural 

 size. Right view of skull, part of teeth restored from other side. 



of the maxillary just in front of the lachrymal depression or vacuity. 

 The anterior borders of the premaxillaries are thick and they do not 

 rise so abruptly as in Mesoreodon or Eporeodon. The prelachrymal 

 vacuities appear to have been (juite large. The sagittal crest was 

 high as shown by impression on surrounding matrix. The anterior 

 portion of the zygomatic arch beneath the orbits is broad, heavy, and 

 widely spreading, the outer portion curving downward, with the 

 border roughened and very concave antero-posteriorly. The anterior 

 lower root is low, being only a little above the alveolar border. The 

 orbit is closed behind by a heavy bridge of bone. The anterior tongue 

 of the squamosal is long and slender, terminating beneath the posterior 

 portion of the orbit. This process and the posterior process of the 

 jugal overlap for a considerable distance. From opposite the glenoid 

 surface the zygomatic arch ascends slightly to where it is broken off 

 opposite the glenoid process. The anterior portion of the arch is 

 broad and thick. It spreads far outward from the molars. The pos- 



