•34 



direction ;i.s in Uil^ latlcr. Tlie fang is robust and gibbous, and comes from 

 the alveolus in a direction downward and forward with a greater degree of 

 divergence than usual among carnivora. The face of Palseosyops, judging 

 from the imperfect specimen, a side-view of which is given in Fig. 51, Plate 

 XVIII, in its complete condition, would appear to resemble in shape that of 

 tiie Elotherinm of White River, Dakota, cxcejit that the muzzle was pro- 

 ■ portionately shorter. Among living animals, it appears to have resembled 

 that of the bears niort; than in those nearly related to it. The zygomatic 

 arches are of rol)ust proportions and widely divergent at their anterior attach- 

 ment to the face. The malar portion of the zygoma is divided by an acute 

 ridge curving from the anterior orbital margin outward, downward, and back- 

 ward. The surface above this ridge curves outwardly and downward from 

 the floor of the orbit continuously. The surface beneath is a broad trilateral 

 plane looking forward, downward, and outward, and is roughened for the at- 

 tachment of a powerful masseter muscle. The space behind the anterior 

 abutment of the zygoma indicates a temporal fossa of large capacity. 



The orbit appears low, and is directed obliquely forward and outward. 

 In advance of the prominent antorbital margin the side of the face is nearly 

 vertical. The infra-orbital foramen is rather large, and is situated over the 

 position of the last premolar. In front of the foramen begins the swell of the 

 large canine alveolus, and below its position is the alveolar border, marked by 

 the vertical ridges of the molar fangs. The hard palate is well arched, and 

 nearly parallel at the sides. Its surface in the specimen is obscured by the 

 attachment of rocky matrix. The breadth of the face at the zygomata 

 appears to have al^out equaled the length. 



The measurements of the specimen are as follows: 



Inches. Liu6s. 



Breadth of face at zygomata ou liue with middle of hxat molar.s 7 8 



Breadtli of face outside of last molars i C 



Breadth of face outside of canine alveoli 3 G 



Breadth of face at infraorbital foramina 3 2 



Breadth of bard palate between last molars 1 7 



Breadth of hard palate between last premolars 1 o 



Distance from back of last molar to fore part of canine S 



For comparison, the measurements of the teeth will be given after the 

 description of the following series. 



Some additional specimens, which I suppose to belong to Palaosyops 

 paludosus., notwithstanding certain dilferences hereafter to be mentioned, con- 



