HORSESHOEING. 



55 



leaves, and every liom-leaf by two fleshy leaves (Fig. 36). The 

 keraphylloiis layer and the horn of the inmost part of the 

 middle or protective layer are always white, even in pigmented 

 (colored) hoofs. 



The horn sole (Fig. 31, /, and Fig. 35, g) is secreted by 

 the velvety tissue of the sole. A sole from which the loose 



Fig. 36. 



Cross-section of keraphyllous and podophyllous laminse (horny and fleshy leaves) : a, inmost 

 part of the solid wall; the horn-tubes approach very close to the horny leaves; b, body of the 

 podophyllous membrane; c, horny portion of a horn-leaf directly continuous with the middle 

 or principal layer of the wall; c', a rudimentary horn-leaf that does not reach the body of the 

 podophyllous membrane; c", cross-section of horny leaves from the sides of which branch 

 many secondary leaves (leaflets) composed of soft (young) horn-cells. These soft cellular 

 horn-leaflets dovetail with the podophyllous or fleshy leaflets; d, podophyllous laminse ex- 

 tending from the body of the podophyllous membrane; d', podophyllous laminse which have 

 branched in their course to the wall, and thus given rise to c', rudimentary horn-leaves; d", 

 cross-section of podophyllous leaflets extending from the sides of the podophyllous leaves; 

 each two such leaflets secrete a keraphyllous leaflet between them; e, injected arterial vessels. 



flakes of old horn have been removed is about as thick as the 

 wall. It covers the under surface of the foot, and presents 

 upon its upper surface a convexity which exactly fits into the 

 concavity on the under surface of the os pedis. This upper 

 surface is thickly covered by a multitude of minute funnel- 

 shaped openings for the reception of the villi of the velvety 

 tissue of the sole (Fig. 37). The lower surface of the sole is 

 more or less concave, rough, uneven, and often covered by loose 



