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



it measures 136 mm., while that of the gigantic Binohyus 

 hollandi would measure about half as much. The process 

 is unique also in that it swings posteriorly in a wide 

 sweeping curve, so that its greatest antero-posterior 

 dimension would be about 200 mm. Looked at from in 

 front, it shows merely a rather thin strip running from 

 the orbit, and for most of its extent is not thicker than 

 20 mm. Only at the point of sending off the process to 

 join the temporal does it thicken to about 30 mm.; it is 

 thin on the margin. 



Measuring across the tips of the dependent processes, 

 the width of the skull would be something over 600 mm., 

 and the length is estimated to be 760 mm. 



The posterior process from the malar bends down as it 

 joins the temporal; it is thin on the outer side, and 

 straight, but on the inner side is curved strongly down- 

 ward, and the tip actually forms a part of the surface of 

 the glenoid cavity. The distance from the notch to the 

 orbit is 68 mm. 



The anterior process from the temporal is triangular in 

 section, probably had a sigmoid lower border and appar- 

 ently extends to a slender point; it is deep, and the dis- 

 tance from the glenoid surface to its upper internal angle 

 is 58 mm. 



The vertical outer edge of the temporal is very slender 

 above the condyle and has a distinct depression poster- 

 iorly, bounded by a narrow margin extending backward. 



The infraorbital foramen lies over the middle of P 3 and 

 is directed upward only slightly. The superciliary bor- 

 der is heavy, but in front of the orbit the rim is thinner. 

 Unlike most entelodonts, the frontals form great smooth 

 planes ; Binohyus has a deep depression just in front of 

 the parietal boundaries, and other genera have deep fold- 

 ings, and a rugose surface. In this specimen a very faint 

 ridge defines the frontals posteriorly, and there are no 

 foramina. 



The teeth (see fig. 16) in some respects seem to resem- 

 ble those of B. hollandi: rugose, angular, irregular. P 1 is 

 very small, is two-rooted and directed strongly forward 

 as indicated by the alveolus. P 2 is rather stout, leans 

 slightly forward, is convex on both sides, strongly so on 

 the outer, and is pitted posteriorly ; it is not curved back- 

 ward nor inward. The widest part is just behind the 

 cusp, and it narrows abruptly before and behind. P 2 is 

 separated from P 1 by about 55 mm. and from P 3 by 11 mm. 



