FOKK FOOT OF THE OX. 
105 
two parts. The antero-interual division presents a deep de- 
pression, whilst the front external is rounded with the lateral 
side of the bone. Supero-posteriorly are two eminences, the 
outer of which is the more prominent. From these eminences 
two ridges extend to the condyles, inclosing an irregular but 
smooth concavity. Inferiorly, we find two surfaces divided by 
a depression, which articulate with the navicular and coffin 
bones. These surfaces are very extensive, particularly the 
outer, which extends both anteriorly and posteriorly half way 
up the bone. 
Each navicular bone , on its upper surface, is rough and nearly 
flat ; and laterally rough and convex. It presents anteriorly 
two depressions unequally divided by a ridge ; these articulate 
with the postero-inferior part of the coronal bone. The posterior 
surface smooth for the passage of the flexor tendons. Infe- 
riorly we see two smooth surfaces, with a deep concavity between 
them : these articulate with the coffin bone. 
The os pedis, or coffin bone , corresponds in shape to the 
hoof, by which it is enclosed. At its postero-superior part are two 
concave surfaces, separated by an elevation of bone, which ends 
superiorly in a tubercle : these correspond for articulation with 
the concavity and the convexities of the small pastern. Antero- 
superiorly, are two ridges with a deep depression between them, 
which is of some extent : these are for the insertion of the ex- 
tensor tendons. There are two foramina on each side of these 
ridges, through which arterial trunks pass into the bone. 
At the posterior part of the os pedis we find two surfaces 
separated by a fissure, which articulate with the navicular bone. 
In this fissure are many small perforations for the passage of 
minute vessels. The external surface is convex, the internal 
concave, and nearly triangular in shape : the inferior surface is 
nearly flat. 
The fetlock joint is formed by the union of the large meta- 
carpal, the two large pasterns , and the four sessamoid bones. 
The ligaments are, 
1st. The capsular which is attached to these bones, around 
their articulating surfaces, and is lined by the synovial mem- 
VOL. IX. 
P 
