ce of the wall. In shape and extent these enlargements vary.
Usually they are rounded and extend from the coronary cushion to the sole,
sometimes only as thick as an ordinary goose-quill, at other times reaching
the size of one's finger. Often they are irregular in formation and
flattened from side to side.

[Illustration: FIG. 132.--A PORTION OF THE HORN OF THE WALL AT THE TOE
REMOVED IN ORDER TO SHOW A KERAPHYLLOCELE ON ITS INNER SURFACE.]

_Causes_.--Keraphyllocele is very often a sequel to the changes occurring
at the toe in laminitis. Probably, however, the most common cause is an
injury upon, or a crack through, the wall. It may thus occur from excessive
hammering of the foot, from violent kicking against a wall or the stable
fittings, and from the injury to the coronet known as 'tread.' It may also
occur as a sequel to complicated sand-crack, and to chronic corn.

That fissures in the wall are undoubtedly a cause has been placed on record
by the late Professor Walley, who noticed the appearance of these horny
growths following upon the operation of grooving the wall.[A]

[Footnote A: _Journal of Comparative Pathology and Therapeutics_, vol. iii,
p. 170.]

This gentleman had a large Clydesdale horse under his care for a bad
sand-crack in front of the near hind-foot, and, as the lameness
was extreme, he adopted his usual method of treatment--viz., rest,
fomentations, poulticing, and the making of the V-shaped section through
the wall, and subsequently the application of an appropriate bar shoe
to the foot, and repeated blisters to the coronet. In a short time the
lameness passed off, and the horse was put to work. A few days later the
animal met with an accident, and was killed.

On examining a section of the hoof it was found that a vertical horny ridge
corresponding to the external fissure had been formed on the internal
surface of the wall, and that a well-marked cicatrix extended upwards
through the structure of the hoof at the part forming the cutigeral groove;
furthermore, _a similar ingrowth had been taking place in the line of the
oblique incisions made for the relief of the sand-crack_.

This case has an important bearing on the operation of grooving the wall,
which operation we have several times in this work advocated for the relief
of other diseases. It teaches us that the incisions should not be carried
so completely through the horn as to interfere with and irritate the
sensitive laminae, and so