334 THE THIGH AND LEG. [CHAP. 



Hippopotamus it is complete and distinct, though slender 

 in proportion to the tibia. In the horse a mere styliform 

 rudiment of the proximal end is present. 



In all Pecora and Tylopoda, a small distinct bone, having 

 a very definite form, articulating with the lower end of the 

 tibia, and forming the external malleolus, appears to 

 represent the distal extremity of the fibula (see Fig. 119). 

 There is occasionally in addition a slender styliform rudi- 

 ment of the proximal extremity, but the two are never united 

 together by bone. 



FIG. 119. Anterior aspect of lower end of the right tibia and fibula of Red Deer 

 (Corns claphus), \. t tibia ; f fibula. 



In the Tragnlina the fibula is long and slender, and com- 

 plete, but its lower end is indistinguishably blended with 

 the tibia. 



The patella is well ossified, and usually somewhat trian- 

 gular, with the broad end upwards ; but fabellrc are not 

 commonly developed in the Ungulata. 



In the Hyrax there is a slight ridge on the femur in the 

 place of a third trochanter. The fibula is complete, and 

 thickest at its proximal end, where it generally ankyloses 

 with the tibia. The styloid process of the tibia articulates by 

 two facets with two corresponding surfaces of the astragalus. 



