134 THE HORSE 



Following the stifle joint is the hock, and this is like the- 

 knee composed of a number of small joints formed between 

 the individual bones of the hock. It is of interest to note 

 in passing that the point of the hock corresponds to the 

 heel in man, whilst the knee is comparable to the wrist, 

 and the stifle to the knee. 



In the horse the metacarpal bones are reduced to 

 three (in man five), and are represented by the back of 

 the hand. The hind Hmbs, as previously stated, are 

 united to the skeleton by means of the pelvic girdle or in- 

 nominate bone, each half of which is composed of three 

 portions, namely, the ilium, the ischium, and the pubis. 

 These are united together by ossification and form a 

 sohd bond of union between the hind limbs and the trunk, 

 the articulation being formed by the bones of the sacrum. 



In looking at the skeleton of the horse (see illustration), 

 the reader will notice the remarkable position which some 

 of the bones occupy, the angles they form, together with 

 the extremely rigid nature of the whole structure. All 

 the bones forming the skeleton present various rough- 

 nesses, depressions, prominences, and other marks 

 indicating the attachments of muscles, Ugaments, tendons, 

 the passage of nerves and blood-vessels, and the coverings 

 of the bones themselves. 



The joints are of interest, as showing the various 

 movements that they are capable of executing, and also 

 the surfaces of the opposing ends of the bones are of 

 additional interest. 



Taking the fore Hmb and commencing at the shoulder 

 joint we find that the lower end of the shoulder-blade, or 

 scapula, shows a cup-shaped depression or concavity, 

 whereas the upper end of the humerus, or arm, presents 

 a large convex surface, the whole joint being closed by 

 what is known as a capsular Hgament. This represents 

 the so-called enerthrodial, or ball-and-socket joint, and 

 it is obviously one which allows a considerable amount of 

 freedom of movement. The same remark is applicable 



