FAULTY CONFORMATION 



141 



stances it is that the horse goes lame, and not with the 

 hoof of normal shape- 

 Seeing, then, that this condition is largely dependent 

 upon the shape of the foot, we may, to some extent, regard 

 it as hereditary. Seeing further, however, that it only 

 appears when shoeing is commenced, we may in a greater 

 degree also regard it as acquired. The lesson, therefore, 

 that this and other forms of contraction should teach us is 

 the carefulness with which the shoeing should be super- 



Fig. 79. — Hoof with Local or Coronary Contractions (as in- 

 dicated at the Points a, a). 



intended in a large stud, or in any case where the animal 

 is of more than ordinary value. 



The explanation of the restricted nature of this form of 

 contraction is simple enough. We have only to refer to 

 the lessons taught by the experiments of Lungwitz, de- 

 scribed in Chapter III., and the condition almost explains 

 itself. We remember that, briefly, the coronary margin of 

 the wall resembles a closed elastic ring, which yields and 

 expands to local pressure, no matter how slight. We 



