DINOGERATA. 563 



together rather narrowl}' transverse. They are separated by a keel which 

 is undivided posteriorly ; anteriorly, the contiguous margins of the cotyli 

 separate. The long axis of the inner of these is directed anteroposteriorly 

 outwards in front; of the other, similar but much more transverse. It 

 overhangs the shaft outward and backward, and supports beneath the sub- 

 roiind down-looking fibular articular surface. The distal articular surface 

 is distinguished from allied species by the downward prominence of the 

 malleolar process, the anteroposterior width, and the greater extent of the 

 fibular articular face. The face is slightly concave anteroposteriorly, and 

 openly sigmoidal transversely. 



Measurements of leg. 



Length with astragalus in place 1.200 



Femnr, length 750 



Femur, diameter of ball 118 



Femur, width at great trochanter 220 



Femur, width at middle shaft 091 



Femur, depth at middle shaft 060 



Tibia, length .' 470 



Tibia, width of proximal surfaces (transverse) 147 



Tibia, width of proximal surfaces (anteroposterior) . 070 



Tibia, transverse diameter of shaft 061 



Tibia, anteroposterior shaft 065 



Tibia, anteroposterior shaft, distal articulation 092 



Tibia, transverse shaft, distal articulation 121 



Fibula, length 430 



Fibula, transverse width at middle 032 



Fibula, width of proximal articular face 042 



Fibula, width of malleolar articular face (transverse) 0.=i2 



Fibula, width of malleolar articular face (longitudinal) 044 



A section of the fibula, near the proximal end, is subtriangular ; a 

 short distance below, subcircular ; on the distal two-thirds it is flat, with 

 the thinner edge convex inward. 



The astragalus is a flat bone, with its entire superior face occupied by 

 the tibial articular surface. This is as broad as long, and very little con- 

 vex. It is broader in front than behind ; the outer margin is concave, the 

 inner slightly convex. The posterior margin projects most on the outer 

 side, and it is divided by a pit-like cavity, which sends a groove to the 

 inner margin. The outer malleolar surface is an anteroposterior oval ; the 

 inner, a concavity, beyond which the inferior portion of the bone projects. 

 The inferior face is divided by a prominent transverse angle, between sub- 



