28 



THE BONES OF THE FOOT. 



healthy, tolerably smooth, and are perforated with a multitude 

 of little holes. The lateral surfaces (fig. 14, c), on the other 

 hand, are always rough. 



- a» 



5. The Pedal Bone or Third Phalanx 

 (Figs. 10 and 11, E: Figs. 16, 17, 18) 



Is the lowest bone of the foot, and is entirely surrounded by 

 the hoof and by soft tissues. It presents three surfaces, three 



prominences, and three borders. 

 The anterior surface responds to 

 the wall of the hoof (fig. 16, a, 

 and fig. 17). In general, it takes 

 the same form as the hoof, that 

 is, it is convex from side to side, 

 is crescent-shaped, and runs 

 obliquely downwards and for- 

 PiG. i6.-Ant'ero-iaterai view ,.f pedal wards or outwards. The autcrior 



bone, ff, anterior surface, which is pro- „„-.t. ^f ^Up n-ni-inr hnvrlpr cjhnw<? n 

 longed upwards to form the pyramidal V^^^ ^^ ^^^^ Uppcr 001 Oer bHOWb A 



process ;/>, upper or articular surface ; ,..„«Vp,l nrmm'npnpp whiph hfm 

 c, outer wing of pedal l)one:</, notch, marKeCl piommeuce, WHILU Jldb 



been called the coronoid process, 

 but has been more correctly de- 

 scribed as the pyramidal process of 

 anatomists. The backward continuation of the outer surface 

 forms on either side a process, termed the wing of the pedal 

 bone (fig. 16, c.c). 



The coronoid or pyramidal process is the highest point of the 

 pedal bone ; from it the borders gradually descend backwards 

 towards the wings. Each of the wings is marked by a deep 

 depression, the preplantar groove, which extends forwards to 

 about the centre of the quarter, where it disappears. This 

 surface is pierced by a large number of holes and fine grooves 

 giving the bone an appearance somewhat resembling pumice- 

 stone. 



The %ipper surface (fig. 16, l, and fig. 17) is for articulation 

 with the coronet bone, but being too small to engage with the 

 whole articular surface of that bone, it is completed behind by 

 the navicular bone. As a whole, this upper surface is crescent- 

 shaped, and falls rapidly away in a backward and downward 

 direction. The centre shows a slight prominence, the sides 



which in cases of "sidebone" is often 

 converted into a foramen. The portion 

 of the wing above this is termed the 

 basilar, that below the retrossal pro- 

 cess ; e, preplantar groove. 



