OSTEOLOGY OF THE HORSE. 65 



Figitre — Irregular. Division — Into body and tuberosity. 



Th k body is the broad or inferior |);irt. It is irregularly con- 

 vex externally, where it is joined with the tuberosity : concave and 

 expanded intCrniilly, where it presents four surfaces for articula- 

 tion with the astragalus, with asperous interspaces for ligament. 

 The inferior part of the body has a narrow articulatory surface, by 

 which it articulates also with the cuboid bone. 



The tuberosity, the projecting part behind, is oblong, flat- 

 tened on its sides, and exhibits a thick tuberous termination, into 

 which is implanted the tendons of the gastrocneniii. The exter- 

 nal side is flattened and roughened by ligamentous connexion ; 

 the internal is smooth, and inclines to concavity, by which a space 

 is left which gives passage to the tendon of the flexor pedis. 



CUBOID BONE (OS CUBOIDES.) 



Silucttion — Outer part of the hock. Form — Oblong, from back 

 to front. Division — Into external, internal, superior, and inferior 

 surfaces. 



'J'he external surface, broad and irregularly curved, is roughen- 

 ed by ligamentous adherence. — The internal surface, irregularly 

 excavated and asperous, exhibits three places of articulation : one, 

 posteriorly, for the great cuneiform ; the other two smaller, one 

 anteriorly, one posteriorly, for the middle cuneiform bone. The 

 superior surface has two articulations, with a little pit between 

 them ; one for the astragalus, a larger one for theos calcis. — The 

 inferior surface presents two articulatory places ; one for the ex- 

 ternal splint bone, the other for the cannon bone. 



THE LARGE CUNEIFORM BONE. (OS CUNEIFORME MAGNUM ) 



Situation — Immediately underneath the nstragalus. 



Figure — Triangular: broadest side turned forwards; salient 

 angle, backwards. Flat, above and below. 



Division— \nio superior and inferior surfaces, sides, and angles. 

 —■The superior surface is entirely articulatory, with the exception 

 of a little rough groove running to its middle from the outer side, 

 which terminates in the medullary hole : it is adapted to the 

 under part of the astragalus. — The inferior surface \s very similar 

 in appearance to the superior, except that it is flat, or rather in- 

 clines to convexity : it articulates with the middle cuneiform, and 

 also, next the internal angle, with the small cuneiform. — I'he sa- 

 lient or posterior angle, has on its external side a surface for arti- 

 culation with the cuboid. 



Connexion With the astragalus, cuboid, middle and small 

 cuneiforni bones. 



