DIXOCERATA. 595 



fibular face is a transverse oval; the inferior much smaller than in E. ^nes- 

 sicornis. This shaft is contracted, and flattened behind and on the inner 

 side. The distal extremity is transverse, less truncated for the fibula than 

 in E. pressicornis, less convex behind, and with a less prominent external 

 malleolus. The point dividing- the astragalus behind is more prominent. 



Measurements of tibia. 



M. 



Total length 398 



Diameter of head, longitudinal 080 



Diameter of head, transverse 138 



Diameter of shaft, transverse 063 



Diameter of shaft, anteroposterior 060 



Diameter of distal articulation, anteroposterior 077 



Diameter of distal articulation, transverse 113 



Diameter of distal extremity, fore and aft 093 



Diameter of distal extremity, transverse 185 



These measurements show that this bone is considerably shorter than 

 in E. pressicornis, though of equal distal diameter. In both species the 

 measurements considerably exceed those given by Marsh for his Titano- 

 iherium (?) anceps. The form of the articular extremities differs from both 

 in being' more narrowed and transverse 



The fibula is larger proximally and smaller distally than in E. pressi- 

 cornis. Diameter proximal articular face .0.^9; of the distal .045. 



The astragalus is similar in size and form to that of E. pressicornis, but 

 differs in two jjoints. The posterior margin is deeply incised for the liga- 

 mentous insertion, and the outer lobe is clearly cut to this fossa, on the 

 inner side. There is a pit for a ligament on the convexity of the inner 

 part of the middle of the tibial articular face. A third difference is seen 

 on the inferior face The inner calcaneal facet is longer and narrower, 

 and is margined on the inner side by a large fossa parallel to its axis, which 

 is wanting in the other species. The calcaneum is short and wide; its only 

 anterior articulation is with the cuboid, and is small. The heel is deeper 

 than long, and is obliquely truncate downward and inward. 



Measurements of cahaneum. m. 



Length lOo 



Width 092 



Depth in front . 056 



Length of hoel 047 



JDepth of heel 055 



i.ength of cuboid facet . 038 



