44 



HORSESHOEING. 



Fig. 26. 



eipal leaves, and the small ones are known as collateral leaves, or 

 simply as leaflets. 



The fleshy leaves (podophyllous tissue) secrete the horny 

 leaves (keraphyllous tissue) and serve to bind the horny wall 

 to the pododerm. The strength of this union is due largely 



to the dovetailing of the 

 horny leaves and their 

 leaflets with the fleshy 

 leaves and their leaflets. 

 4. The fleshy sole or 

 velvety tissue of the sole 

 (Fig. 25, 6) is that part of 

 the pododerm which cov- 

 ers all the under surface 

 of the foot except the 

 plantar cushion, the bar 

 laminae, and the bar 

 portion of the coronary 

 band. It is sometimes 

 slate-colored or studded 

 with black spots, but is 

 usually dark red. It is 

 thickly set with villi, 

 which are especially long 

 and strong* near its pe- 

 riphery. The fleshy sole 

 covers the solar venous plexus, or net-work of veins, and se- 

 cretes the horny sole. 



5. The velvety tissue of the frog (Fig. 25, c) covers the lower 

 surface of the plantar cushion, and in the region of the bulbs (e) 

 passes insensibly into the perioplic band. In comparison with 



* In order to see the length, thickness, and abundance of the villi of the 

 pododerm, place the foot deprived of its hoof in a clear glass jar and cover 

 it with water, renewing the latter until it is no longer tinged with blood. 

 The result is astonishing. 



Side TioA ^1 L^^i/f i»wL.i,i; i^i„„,„a : a, the perioplic 

 hom-lDand ; it is swollen from prolonged maceration in 

 water ; tlie upper border shows adhering hairs ; the 

 inner surface (perioplic groove) presents many minute 

 openings ; a', the perioplic hom-hand broadens in 

 passing over the bulb or glome of the heel, and is 

 finally lost in the homy frog ; a", section of wall re- 

 moved. That part of hoof on the right of 6 is called 

 the toe; between 6 and c is the side wall or "mamma," 

 and between c and d the "quarter;" e, projecting 

 homy frog ; /, coronary groove with numerous minute 

 ojienings ; g, keraphyllous layer of the wall (homy 

 leaves). 



