378 



THE PASTERXS. 



has tv/o depressions to receive the protuberances on the lower head 

 of the upper bone, bearing some resemblance to a pulley, but not so 



Fiy. 1. 



Fig. 2. 



Fig. 1. 

 a The upper pastern. 

 h The lower pastern. 

 c The navicular bone. 

 d The coffin-bone. 



Fig. 2. 

 a The scsamoid-bone. 

 b The upppr pastern. 

 c The lower pastern. 

 d The navicular bone 

 e The coffin-bone. 



decidedlyas the lov^^er head of the shank-bone. Itslower head resembles that 

 of the other pastern, and has also two prominences, somewhat resembling 

 a pulley, by which it articulates with the coffin-bone ; and a depression in 

 front, corresponding with a projection in the coffin-bone. There are also 

 two slight depressions behind, receiving eminences of the navicular bone. 

 Neither of these joints admits of any lateral motion. The ligaments of this 

 joint, both the capsular and the cross ones, are, like those of the pastern- 

 joint, exceedingly strong. The tendon of the extensor muscle is inserted 

 into the forepart both of the upper and lower pastern- 

 bones, as well as into the upper part of the coffin-bone; 

 and at the back of these bones the suspensory liga- 

 ment is expanded and inserted, while a portion of it 

 goes over the fore part of the upper pastern to reach 

 the extensor tendon. These attachments in front of 

 the bones are seen in the accompanying cut, in 

 which a represents the lower part of the shank- 

 bone ; h the sesamoid-bones ; c the upper pastern ; 

 d the lower pastern ; and e the coffin-bone ; / one 

 of the two branches of the suspensory ligaments 

 going to unite with the extensor tendon ; g the long 

 extensor tendon ; h ligaments connecting the two 

 ■ x^ pastern-bones together ; / the lateral cartilages of 

 the foot, and h the coronary ligament. 

 The length and obliquity of the pastern vary in the diffiii^ent breeds of 

 horses, and on it depends the elastic action of the animal, and the easiness 

 of his paces. The pastern must be long in proportion to its obliquity, or 

 the fetlock will be too close to the ground, and, in rapid action, come vio- 

 lently into contact with it. It is necessary that the fetlock should be 

 elevated a certain distance from the ground, and this may be effected either 

 by a short and upright, or a long and slanting pastern. In proportion as 

 the pastern is oblique or slanting, two consequences vnll follow, less weight 

 will be thrown on the pastern, and more on the sesamoid, and, in that 

 proportion, concussion \n\\ be prevented. 



Every advantage, however, has, to a certain extent, its corresponding 

 disadvantage. In proportion to the obhquity or slanting of the pastern, 

 will be the stress on the fetlock-joint, and, therefore, the liability of that 



