1873.] ^' [Cope. 



lar surface is distinguished from allied species by the downward promi- 

 nence of the malleolar process, the antero-posterior width, and the greater 

 extent of the fibular articular face. The face is slightly concave antero- 

 posteriorly and openly sigmoidal transversely. 



Measurements of Leg. 



M. 



Length with astragalus in place 1.200 



Femur, length 750 



" diameter ball 118 



" width at great trochanter 220 



" " middle shaft 091 



depth " " 060 



Tibia, length 470 



" width proximal surfaces (transverse) 147 



" " " (antero-posterior) 070 



" transverse diameter shaft 061 



" antero-posterior " 065 



" " " distal articulation 092 



" transverse " " " 121 



Fibula, length 430 



" transverse width at middle 032 



" width proximal articular face 042 



" " malleolar " " (transverse) 052 



" " " " " (longitudinal) 044 



A section of the fibula, near the proximal end, is sub-triangular ; a 

 short distauce below, sub-circular; on the distal two-thirds it is flat, with 

 the thinner edge convex inwards. 



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 

 convex. 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 antero-posterior 

 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-anterior and sub-posterior faces. The latter receives 

 the calcaneum on two oval surfaces, which are joined behind by a narrow 

 strip. The navicular face is sub-rhomboid, the cuboid one-third as large, 

 and triangular, with a round base outwards. The margin of the former 

 scarcely projects beyond the superior face. 



Measurements of Astragalus. 



M. 



Total width 0.128 



" length 107 



Width tibial face in front 090 



a. r. s. — VOL. XIII. H 



