42 ANATOMY OF THE HORSE. 
ward. It is bi-convex from before backward, consisting of two 
condyloid prominences, parted by a shallow transverse depression. 
It is adapted to a counterpart articulatory formation in the coffin 
bone. 
Connexion— With the pastern, coffin, and navicular bones. 
OF THE FOOT. 
The foot, or third phalanx, forms the resting, bearing, or ter¬ 
minating part of the limb. The coffin bone constitutes its bony 
fabric, to which the navicular may be regarded as an appendage. 
THE COFFIN BONE. (OS PEDIS.) 
Situated within the hoof, which it nearly resembles in 
Form —Being in its outline semi-lunar: anteriorly and superi¬ 
orly, convex; posteriorly and infenorly, concave. Its shape vanes 
with the natural make and morbid changes in the form of the 
hoof. 
Division —Into wall, sole, tendinous surface, articulatoiy sur¬ 
face, and wings. . 
The wall is the semicircular prominent part in front, and 
corresponds to the wall or crust of the hoof. It is convex most 
so, anteriorly; it possesses a certain degree of declivity, which 
increases in degree, but decreases in extent, as we pioceed fiom ; 
the front to the sides, the greatest elevation of the wall presenting 
anteriorly; and it exhibits every where a fun owed and porous 
surface: the furrows, which run from above downwaids, being| 
most distinct inferiorly and laterally ; and the foramina consisting 
of a large and small set, of which the large only are numerable or 
worthy of particular notice, the small ones being infinite, and 
numbers of them even imperceptible. The foramina (for the large 
are alone worthy of the name, the small being simply poiosities) 
are regularly disposed in so far, that we invanably find seveial of 
them ranged at nearly ecpial distances around the circumfeience 
of the wall, a little above its edge; and two others at or near the 
terminations of two grooves, which come from the wings, and run 
along the sides of the wall: five or six others are commonly seen 
within the intermediate space, between the two latter. Through 
the foramina pass blood-vessels and nerves in and out of the inte-j 
rior of the bone. The 'porosities serve mostly for the fibrous 
attachment of the laminae. J 
The inferior or circumf event edge of the wall is rather semi-oval 
than semi-circular. It is notched or serrated, paiticulaily towaidsj 
the sides, where, in places, the notches opposite to the foiaminal 
widen into gaps, in order to give passage to blood-vessels to the 
