THE BONES OP THE PORE EXTREMITIEIS. 305 



long in animals of speed and short where speed is not re- 

 quired : this bone is also strong alld cylindrical. 



The ulna, or bone which forms the elbow, does not sup- 

 port the weight, but serves for the attachment of the power- 

 ful muscles so conspicuous in a shoulder of mutton and 

 which are generally divided by the first cut. For thi^ pur- 

 pose it is attached to the radius, and rises above the elbow- 

 joint, the back of which it forms, but does not reach the 

 knee: This joint, the carpus, is composed of seven bones, 

 arranged in two rows, the upper of which articulates with 

 the radius, and the lower with th^ cannon or metacarpus. 



The metacarpus or shank much resembles that of the 

 horse, until it reaches the fetlock, where it is to some little 

 extent cloven, so as to articulate with the double arrange- 

 ment of the bones below. Instead of the two small meta- 

 carpal or splent-bones that we find in the horse, there is 

 merely one, and that of small extent and use. 



The small bones situated at the back of the fetlock, called 

 the sesamoids, and which serve as levers for the attachment 

 of ligaments and the action of the sinews, are double those 

 of the horse, being four in number. 



The bones below the fetlock, viz., the large pastern or os 

 suffraginis, the small pastern or os corones, the os pedis or 

 cofiin-bone, and the navicular bone,' axe all double, and, like 

 the same parts in the ox, somewhat resemble in shape the 

 bones of the horse sawn in two. 



AH these joints have less extent of motion than we find 

 in the horse, and the bones therefore present a more upright 

 appearance. In the horse and in the ox an angle is formed 

 at the fetlock with various degrees of obliquity, and the three 

 bones below pass down in a straight line though in an ob- 

 lique direction. In the sheep, however, there is a different 

 conformation ; the large pastern-bone passes down in an ob- 

 lique forward course, as in the ox, but the small pastern de- 

 scends in a perpendicular direction so as to form an angle 

 with the bone above almost as great as, though precisely op- 

 posite to, that of the fetlock-joint. This it is which gives 

 the more upright appearance to these parts in sheep, though 

 the cause is not externally visible, and it throws the centre 

 of gravity on the back part of the cofiin-bone and on the 

 horny heels of the foot-. The small pastern bone is rela- 

 tively longer than in the horse, and there is more motion in 



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