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extensor tendon through the mediuin of dense cellular tissue. It 

 secretes the homy tissues of the wall. The coronary band pre- 

 sents, along its upper border, a narrow lip or process — the peri- 

 oplic ring — which secretes the horn of the periople, the thin outer 

 covering or varnish of the wall. 



The sensitive lajnince. 



The sensitive lamince form the continuation of the coronary 

 substance and are attached to the cofBn bone by dense, fibrous 

 membrane which contains a large number of blood vessels that 

 pass through the small openings in the coffin bone. The highly 

 organized plates are interposed and firmly attached to the horny 

 lamince of the wall and are covered by numerous papillce, which 

 secrete the horny lam ina>. On their inferior extremity are a few 

 papillae, which help to secrete the horny sole. 



The sensitive sole. 



The sensitive sole, continuous with the sensitive laminae and 

 frog, is firmly attached to the coffin bone. It secretes the horny 

 sole. 



PHYSIOLOGY OP THE FOOT. 



The amount of moisture contained in the horn is considerable, 

 the use of which is to keep the foot elastic and prevent it from 

 beconaing brittle. 



In the unmutilated foot the too rapid evaporation of moisture 

 in the wall is prevented by the periople; from the sole and frog 

 by the accumulated masses of partly dead layers of horn; con- 

 sequently, those protecting layers should not be removed, as 

 this removal would cause the horn to become dry, brittle, and 

 inelastic. 



The wall is the weight-bearing portion of the hoof; the growth 

 is three-eighths of an inch per month. 



The bars afford a solid bearing to the posterior part of the foot, 

 to give additional strength and to secure a more intimate union 

 with the sole. They act as buttresses and assist in expanding 

 the hoof on pressure. 



The function of the sole is to afford protection to the sensitive 

 sensitive parts above. 



