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narrow leaves, or plates. Their form, and the nature of this 

 substance has given them the name of horny laminae. In the 

 detached hoof, it will be seen that one longitudinal edge is 

 free, while the other is united to the wall. It is, indeed, a por- 

 tion of the wall itself, frilled as it were into the form we view it. 

 By means of these plates, averaging about 500 in number, the 

 wall is attached to the internal portion of the foot, namely, to 

 the pedal bone, and it extends to the lateral and inferior car- 

 tilages. Besides forming an attaching medium of great strength 

 and tenacity and large extent, they subserve other important 

 purposes which will be referred to a little further on when re- 

 viewing these functions more particularly. 



THE EPIDERMIS, OR CUTICLE OF THE WALL. 



A not unimportant constituent of the wall is its extreme ex- 

 ternal coating. Physiologists tell us that the normal hoof is 

 covered by a layer of a silicious material resembling that upon 

 the outer surface of straw, and that it fulfils a similar function 

 to the wall of the foot as that of the epidermis or cuticle, to 

 the dermis or true skin. The healthy foot is able to secrete 

 and maintain a degree of moisture compatible with the exis- 

 tence of toughness and resiliency in its outer structures, and 

 any excess or deficiency of moisture is equally pernicious to a 

 healthy foot. 



The former is promoted by the injudicious use of the knife 

 and rasp, conjoined with soaking, stopping, poulticing, etc., 

 while the latter is the result of the same unreasoning process 

 of rasping and paring, with the soaking and stopping omitted. 

 Whenever the epidermic covering is removed by the rasp, as is 

 too frequently the case, undue evaporation takes place, and 

 the hoof becomes the very opposite of what it should be, under 

 the combined influences of inordinate exhalation of moisture, 

 and the heat of the sun, or an unusually dry atmosphere. The 

 subject is suggestive of much more that might be said, but must 

 be reserved for future consideration. 



