s lost its
natural, clear, dark luster, which is replaced by a brownish or
yellowish sere-leaf color. This is more marked in proportion as the iris
is inflamed, and less so as the inflammation is confined to the choroid.
The quantity of flocculent deposit in the chamber of the aqueous humor
is also in direct ratio to the inflammation of the iris. Perhaps the
most marked feature of internal ophthalmia is the extreme and painful
sensitiveness to light. On this account the lids are usually closed, but
when opened the pupil is seen to be narrowly closed, even if the animal
has been kept in a darkened stall. Exceptions to this are seen when
inflammatory effusion has overfilled the globe of the eye, and by
pressure on the retina has paralyzed it, or when the exudation into the
substance of the retina itself has similarly led to its paralysis. Then
the pupil may be dilated, and frequently its margin loses its regular,
ovoid outline and becomes uneven by reason of the adhesions which it has
contracted with the capsule of the lens, through its inflammatory
exudations. In the case of excessive effusion into the globe of the eye
that is found to have become tense and hard so that it can not be
indented with the tip of the finger, paralysis of the retina is liable
to result. With such paralysis of the retina, vision is heavily clouded
or entirely lost; hence, in spite of the open pupil, the finger may be
approached to the eye without the animal's becoming conscious of it
until it touches the surface, and if the nose on the affected side is
gently struck and a feint made to repeat the blow the patient makes no
effort to evade it. Sometimes the edges of the contracted pupil become
adherent to each other by an intervening plastic exudation, and the
opening becomes virtually abolished. In severe inflammations pus may
form in the choroid or iris, and escaping into the cavity of the aqueous
humor show as a yellowish-white stratum below. In nearly all cases there
is resulting exudation into the lens or its capsule, constituting a
cloudiness or opacity (cataract), which in severe and old-standing cases
appears as a white, fleecy mass behind a widely dilated pupil. In the
slighter cases cataract is to be recognized by examination of the eye in
a dark chamber, with an oblique side light, as described in the
introduction to this article. Cataracts that appear as a simple haze or
indefinite, fleecy cloud are usually on the capsule (capsular), wh