s will be needed. As the new quarter
grows out, the lameness disappears, and the patient may be shod with a
bar shoe and returned to work.

In all cases of sand crack the growth of horn should be stimulated by
cauterizing the coronary band or by the use of blisters. In simple
quarter crack recovery will often take place if the coronet is
blistered, the foot shod with a "tip," and the patient turned to
pasture.

The shoe in toe crack should have a clip on each side of the fissure and
should be thicker at the toe than at the heels. The foot should be
lowered at the heels by paring, and spared at the toe, except directly
under the fissure, where it is to be pared away until it sets free from
the shoe.

When any of the complications referred to above arise, special measures
must be resorted to. For the proper treatment of gangrene of the lateral
cartilage and extensor tendon and caries of the coffin bone reference
may be had to the articles on quittors. If the horny tumor, known as
keraphyllocele, should develop, it is to be removed by the use of the
knife. Since this tumor develops on the inside of the horny box and may
involve other important organs of the foot in disease, its removal
should only be undertaken by a skillful surgeon.

NAVICULAR DISEASE.

Navicular disease is an inflammation of the sesamoid sheath, induced by
repeated bruising or laceration, and complicated in many cases by
inflammation and caries of the navicular bone. In some instances the
disease undoubtedly begins in the bone, and the sesamoid sheath becomes
involved subsequently by an extension of the inflammatory process.
(Plate XXXIV, fig. 5.)

The Thoroughbred horse is more commonly affected than any other, yet no
class or breed of horses is entirely exempt. The mule, however, seems
rarely, if ever, to suffer from it. For reasons which will appear when
considering the causes of the disease, the hind feet are not liable to
be affected. Usually but one fore foot suffers from the disease, but if
both should be attacked the trouble has become chronic in the first
before the second shows signs of the disease.

_Causes._--To comprehend fully how navicular disease may be caused by
conditions and usages common to nearly all animals, it is necessary to
recall the peculiar anatomy of the parts involved in the process and the
functions which they perform in locomotion.

It must be remembered that the fore legs largely support the weight of
the bod