THE LIM13S 



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increased by folds, ridges, papillse, or villi. This vascular 

 and sensitive structure, the 4 matrix of the hoof,' 6 sub- 

 corneous integument,' or 4 keratogenous membrane,' 

 as it has been called, may be divided into three portions, 

 differing in position and structure : — 



1. A rounded, prominent ridge Q coronary cushion '), 

 convex from above downwards (fig 25, 12), constitutes 

 the upper edge of the hoof-matrix, immediately conti- 

 guous to the hairy skin. It encircles the front and side 

 of the toe, descending on each side behind and becoming 

 continuous with the prominences called respectively the 

 glomes, branches, and body of the frog. Its surface is 

 everywhere covered with numerous and well- developed 

 little threadlike prolongations, which, if it is placed in 

 water, float out, and give the surface a velvety appear- 

 ance. These papillae fit into corresponding tubular 

 depressions in the epidermic covering. Prom the 

 coronary cushion the base of the 6 wall ' of the hoof (to 

 be hereafter described) grows; it therefore exactly corre- 

 sponds to that portion of the matrix of the human nail 

 which forms the bottom of the semilunar groove. 



2. Below this, and separated from it by a narrow 

 whitish band, the membrane has a very different ap- 

 pearance. It closely covers the front and sides of the 

 bone as far as its lower margin, and posteriorly on each 

 side is continued round the hinder border of each of the 

 lateral wings, and turns forward to reach almost the 



