107 



Lines. 



Bread tli fore and aft of the outer articular facet for the astragalus 23 



Breadth transversely of the inner articular facet for the astragalus : 18 



Breadth fore and aft of the inner articular facet for the astragalus , 24 



Breadth transversely of the articular facet for the cuboid 14 



Breadth vertically of the articular facet for the cuboid 10 



Astragalus. 



Lines. 



Greatest breadth fore and aft of the astragalus at inner side 50 



Greatest breadth transversely of the astragalus 52 



Greatest thickness of astragalus 32 



Breadth of tibial articular surface at middle transversely 38 



Breadth of tibial articular surface at middle fore and aft t 32 



Breadth of articular facet for scaphoid 40 



Depth of articular facet for scaphoid 28 



Cuboid. 



Lines. 



Depth of the cuboid 25 



Breadth of the cuboid inferiorly : 25 



Length of the cuboid at center 15 



The canine tooth, originally described and referred to a carnivore with the 

 name of Uintamastix atrox, is represented in Figs. 1 to 3, Plate XXV. The 

 specimen is broken into two pieces, is mutilated at the point, and lias lost 

 apparently several inches of the base. In its perfect state the tooth approxi- 

 mated a foot in length, of which it now retains about three-fourths. It is saber- 

 like in general form — long, laterally compressed cylindroid, and moderately 

 curved. It appears more curved at the base, and from this position, also, has a 

 somewhat outward deflexion, so that the tooth in its course curved forward and 

 downward with an outward divergence. Laterally from the base it gradually 

 tapers to the point; fore and aft it gradually narrows to near the lower third, 

 when it becomes slightly expanded before tapering, so as to assume the shape 

 of a lance-head. This likeness is rendered more striking internally by the sur- 

 face being concavely impressed in front and behind the axis extending toward 

 the trenchant borders of the lance-head extremity. Externally, it is impressed 

 in like manner to a less extent posteriorly, but not anteriorly. Above the 

 lance-head extremity of the tooth it is obtusely rounded in front and behind, 

 and in this position is elliptical in transverse section, as represented by the 

 outline, Fig. 5. A section near the middle of the lance-head extremity has 

 the form represented in Fig. 4. 



The tooth, so far as the specimen extends, appears to have been invested 

 with thin enamel throughout. Externally, it reaches to the broken edge of 



