OSTE0L0(iY OF THE HORSE. . O/ 



SESAMOID BONES, (OSSA S F.S A M Ol DE A.) 



Nitmbei- — Two. — Situated at the back of the articulation formed 

 by the pastern and cannon bones. 



Fortn — Trapezoid ; three of the sides presenting triangular 

 faces, whose apices unite in one point, which is directed upwards, 

 and whose bases form the fourth side; turned downwards. 



Division — Into three sides, basis, and apex. 



The anterior surfaces are excavated, smooth, and articulatory, 

 and along their inward borders, which are opposed to each other, 

 are bevelled oft, by which, by the two together, a groove is formed 

 for the reception of the middle eminence of the cannon bone ; 

 while the concavities extend the articulatory surface for the con- 

 dyles of that bone. — The posterior surfaces are convex and 

 asperous, for the attachment of the suspensory ligament : the 

 two together form a sort of channel between them, in which run 

 the flexor tendons. — The lateral surfaces, which are grooved as 

 well as roughened, receive the branches of the suspensory liga- 

 ment. — The bases grow narrow as they approach each other: 

 their surfaces are rendered uneven by the attachment of the long 

 and sliort inferior and crucial ligaments. 



Connexion — These bones are articulated only with the large 

 metacarpal ; they are connected both with that and the pastern 

 bone. 



OF THE CORONET. 



This part answers to the second phalanx of the human foot. It 

 has for its base, the 



CORONET BONE. (oS CORONiE.) 



Situation — Between the pastern and foot. 



Figure — Nearly square; its breadth exceeding its longitudinal 

 diameter only by about one- fifth. It has four surfaces. 



The superior suiface is bi-concave — being divided by a simple 

 transverse eminence into two ovoid concavities, into which are 

 fitted the condyloid projections of the pastern bone : this eminence 

 is bounded before and behind by small tubercular elevations ; the 

 posterior receives part of a ligament : the anterior, a portion of 

 the extensor tendon. Laterally and posteriorly, the surface is 

 extended by two projections, to which are fixed the lateral 

 ligaments. 



The anterior surface is convex, but irregular and asperous. 

 Inferiorly, its sides present two remarkable depressions, into 

 which are implanted the terminating branches of the tendo per- 

 foratus : above and between them, the bone is roughened by the 

 attachment of the extensor tendon. 



