the two splint bones, until near
the fetlock, where it divides and sends a branch on each side of the
joint, downward and forward, to become attached on the sides of the
extensor tendon at the lower end of the pastern bone. As it crosses the
sesamoids, on the posterior borders of the fetlock, it throws out fibers
which hold it fast to these bones. (Plate XXXIV, fig. 2.)

The pastern joint is made by the union of the two pastern bones.

The coffin joint is made by the union of the small pastern, coffin, and
small sesamoid, or navicular bones, the latter being set behind and
beneath the joint surface of the coffin bone in such way as to receive
largely the weight of the small pastern.

Three tendons serve to move the bones of the foot one on another. Two of
these flex, or bend, the joints, while the other extends, or
straightens, the column of bones. (Plate XXXIII, fig. 5.)

The flexor pedis perforans, or deep flexor of the foot, passes down
behind the cannon bone, lying against the suspensory ligament in front,
crosses the fetlock joint in the groove made by the union of the two
sesamoids, and is attached to the bottom on the coffin bone, after
covering the navicular, by a wide expansion of its fibers. It is the
function of this tendon to flex the coffin bone and, with it, the horny
box.

The flexor pedis perforatus, or superficial flexor of the foot, follows
the course of the preceding tendon and is attached to the middle of the
ankle. The function of this tendon is to flex the foot at the fetlock.

The extensor pedis runs down in front of the leg, is attached on the
most prominent point of the coffin bone, and has for function the
straightening of the bones of the ankle and foot.

The bones, ligaments, and tendons are covered by a loose connective
tissue, which gives a symmetry to the parts by filling up and rounding
off, and all are protected by the skin and hoof.

The skin of the fetlock and ankle is generally characterized by its
thickness and the length of its hairs, especially around the hind parts
of the fetlock joint in certain breeds of horses. The most important
part of this envelope is that known as the coronary band.

The coronary band is that portion of the skin which secretes the horn of
which the wall of the hoof is made. This horn much resembles the nail
which grows on the fingers and toes of man. It is composed of
cylindrical tubes, which are held together by a tenacious, opaque
matter. The ho