766 



THE SENSE ORGANS AND SKIN OF THE HORSE 



The superior or inner surface is convex, and slopes with a varying degree of 

 obliquity downward to the convex border. It presents numerous small funnel-like 

 openings which contain the papilla? of the sole matrix in the natural state 



Wall 



Lamirue of wall 



Landnar matrix 



Third phalatix 



Plantar cushion 



Bar 



Frog 



Space between 

 bar and frog 



Angle of heel 



Periople of heel 



Fig. 574. — CRo.ss-sECTio.Nf of Foot of Horse, Cut Parallel with the Coronary Border, 



The inferior or ground surface is the converse of the preceding. It is normally 

 arched — and more strongly in the hind than in the fore foot — but the curvature is 

 subject to wide variation; in heavy draft horses the sole is commonly less curved 



Periople 



Coronary 



groove 



White line 



Sole 



Lateral ridge 

 (frog and bar) 



Periople of heel 



Fu;. 575. — Half of Hoof of Horse, Internal Surface 



than in the lighter breeds and may even be flat. The surface is usually rough, 

 since the horn exfoliates here in irregular flakes. 



The convex border is joined to the wall by relatively soft horn, previously 



