466 NAMES OF EXTERNAL PARTS. 



line of the frog. In healthy feet, it consists of only a 

 slight depression. In a disease, called " thrush," of 

 the sensitive part which secretes the frog, the cleft 

 forms a deep, damp and foul-smelling fissure, and the 

 frog becomes more or less shrivelled up. The frog 

 similar to the skin of the palms of our hands, requires 

 frequent pressure to make it thick and strong. The 

 horn of the hoof is merely a modification of the cuticle 

 (scarf skin). 



The bars of the hoof are the portions of the wall of 

 the hoof which are turned inwards at the heels, and run 

 more or less parallel to the sides of the frog. The sole 

 is that portion of the ground surface of the foot which 

 is included between the wall, bars and frog. 



The pastern (9) is the short column of bones (two 

 in number) which lies between the fetlock and hoof. 



The fetlock (8) is the prominent joint which is just 

 above the hoof. 



The cannon bone (7) is the bone that extends from 

 the fetlock to the knee (6), which, in the horse, corre- 

 sponds to our wrist. 



The back tendons or back sinews (M) form the 

 more or less round tendinous cord which is at the 

 back of the leg, from the knee (or hock) to the fetlock. 

 These tendons, which are two in number, usually 

 appear in the form of one cord ; but in horses which 

 have a very fine skin and "clean legs," we may see 

 that one of them is placed behind the other. The 

 term " clean legs " signifies that the limbs are not only 

 sound, but are also free from any fulness, which would 



