68 THE PROTECTIVE STRUCTURES OF THE FOOT. 



an inch in length, which, from their close apposition, give to 

 this part of a freshly-stripped foot a shining appearance, 

 especially when the surface is rubbed with the finger or with 

 any hard body, thus at once distinguishing the perioplic ring 

 from the hair-bearing cutis above, which has a finely- 

 punctated appearance, and from the coronary band, which 

 has a rougher look. The perioplic ring produces the soft horn 

 of the periople and the superficial layer of the wall. The 

 periople has been regarded as a portion of the coronary band ; 

 but, as the horn which it secretes differs in many respects from 

 that of the coronary band, it has been thought well to distin- 

 guish it from that structure, and to regard it as a separate 

 portion of the horn -secreting corium. 



To show that this superficial layer of horn is not merely a 

 layer of epidermis, which it was long thought to be, a foot 

 should be sawed through in a circle about an inch below the 

 coronet until the sensitive structures are reached, and macerated 

 for a few days. The portion thus divided may then be sepa- 

 rated from the other parts of the hoof, and, with the exercise 

 of some care, may slowly be detached from the foot. During 

 the act it will be seen that the fine papilhi' of tlie perioplic ring, 

 described by Leisering, are drawn out of their horny sheaths, 

 just as the papillte of the coronary band are drawn from the 

 depressions in which they lie in the horn of the coronet. 



2. The Coronary Band. 

 (Figs. 40 and 41, c.) 



The coronary band is a rounded structure about ^ of an 

 inch wide, which encircles the foot from the region of one bulb 

 to that of the other, and is situated between the perioplic ring 

 and the upper extremities of the sensitive laminse. It is divided 

 from the perioplic ring by the above-mentioned " coronary 

 groove," and is so related to the underlying parts that, at the 

 front of the foot, its upper border extends above the highest 

 part of the pyramidal process of the pedal bone, and lies in 

 front of the lower third of the coronet bone, where it covers 

 the extensor pedis tendon. Its sides stretch obliquely backwards 

 and downwards, covering the lateral surfaces of the coronet 

 ])one and the supero-anterior part of the lateral cartilage. It& 



