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THE STRUCTURE OF THE HORSE 



and fibular in the hind limb) and internal (radial in 

 the fore and tibial in the hind limb). 



The flexure between the middle and distal segments 

 of the limb is called the ' wrist-joint ' and ' ankle-joint ' 

 in the fore and hind limbs respectively in man, which 

 correspond with those called the 6 knee ' and the ' hock ' 

 in the horse. 



These are the essential characters in which the fore 

 and hind limbs resemble each other. Of the differences 

 many are merely adaptive to the different purposes to 

 which they are put. The perfect efficiency of action, 

 even in those that bear the closest resemblance, is 

 secured by a partial rotation on its axis of each from 

 the shoulder or hip as the case may be, so that the 

 outer side of the hind limb at the next joint comes to 

 correspond with the inner side of the fore limb ; but, 

 owing to a second rotation in the middle segment in the 

 latter, the last segments, or hand and foot, are brought 

 again into corresponding positions in the ordinary 

 walking attitude, the first (radial and tibial) digits 

 being on the inside edge, and the fifth (ulnar and 

 fibular) on the outside. Besides these differences, there 

 are others, the signification of which is not so clear, 

 constantly met with in the arrangement of the bones of 

 the carpus and tarsus. Moreover, it may be noted that 

 the joint between the first and second segments of the 

 hind limb (knee-joint) has almost always a special bone 



