AESmOITHEEItTM. 



53 



stouter, having a larger cnemial crest and a more regularly concave astragalar 

 surface. 



The fibula (text-fig. 31) possesses a slender strongly-curved shaft with expanded 

 articular ends. The upper end bears on its tibial face (t!) a flattened or even slightly 

 concave facet for union with the tibia ; the outer face is swollen and roughened, and 

 is partly divided into two by a longitudinal groove. The shaft is slender and is 



Text-fig. 31. 



Left fibula of ArsinoifJierium zitteli : A, inner (tibial) face ; B, outer face ; C, distal end. 



ast., surface for astragalus ; cede, surface for calcaneum ; e.m., external malleolus ; t., distal tibial surface ; 



*.', proximal tibial surface. | nat. size. 



compressed from before backwards, bearing on its inner face a longitudinal ridge ; 

 it is strongly curved, the convexity being on the tibial side. The distal third of the 

 shaft is greatly expanded and deeply concave, being closely applied to the outer 

 side of the distal portion of the tibia. Distally this deep concavity is closed by 



