HORSESHOEING. 



27 



inner and outer branches {c, c) or wings of the os pedis. The 

 upper, articular surface (6) slopes backward and downward. 

 The lower, solar or plantar surface (Fig. 8, a) is slightly con- 

 cave, and presents posteriorly a half-moon-shaped excavation, 

 with a roughened border called the semilunar crest (c), to which 

 the perforans tendon attaches; just above this crest are two 

 small holes (e) known. a^ the plantar foramina, through which 

 the plantar arteries pass into the bone. The surfaces of wall 

 and sole come together in a sharp edge, which is circular in its 



Fig. 7. 



Fig. 8. 



Oa pedis seen in profile and in front; a, 

 anterior face with pyramidal eminence 

 above; b, joint-surface; c, wings or branches 

 of hoof-bone; d, notch which, by the attach- 

 ment of the lateral cartilage, is converted 

 into a foramen and leads to e, the preplan- 

 tar fissure. 



Lower surface of hoof-bone; o, anterior 

 portion covered by the velvety tissue of the 

 sole; 6, wing of the os pedis; c, semilunar 

 crest, to which the perforans tendon at- 

 taches; d, plantar fissure leading to e, plan- 

 tar foramen. 



course. It is easy to tell whether a pedal bone is from a fore 

 or a hind limb; the os pedis of a hind leg has a steeper and 

 more pointed toe, and a more strongly concaved solar surface 

 than the same bone of a foreleg. Not only is the outline of the 

 sharp inferior border of the os pedis of a front foot more rounded 

 at the toe, but when placed on a flat surface the toe does not 

 touch by reason of being turned slightly upward, much as a 

 shoe designed to give a " rolling motion." The os pedis of a 

 hind foot is narrower from side to side (pointed), and does not 

 turn up at the toe. 



The right and left hoof-bones are also, as a rule, easily dis- 



