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for the aqueous liumor and the condition of the iris and pupil. The 

 aqueous humor is usually turbid, and has numerous yellowish white 

 flakes floating on its substance or deposited in the lower part of 

 the chamber, so as to cut ofi: the view of the lower x^ortion of the 

 iris. The still visible portion of the iris has lost its natural, clear 

 dark luster, which is replaced by a brownish or yellowish sere-leaf 

 color. This is more marked in jn'oportion as the iris is inflamed, and 

 less so as the inflammation is conflned to the choroid. The amount 

 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 sensitive- 

 ness to light. On this account the lids are usually closed, but when 

 opened the puj)il is seen to be narrowly closed even if the animal has 

 been kept in an obscured stall. Exceptions to this are seen when 

 inflammator}' efllusion has overfilled the globe of the eye, and by pres- 

 sure on the retina has paralyzed it, or when the exudation into the 

 substance of the retina itself has similarly" led to its paralj^sis. Then 

 the puiDil 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 inflammator}^ 

 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 tij) of the finger. With such paralysis of tlie retina, 

 vision is heavily clouded or entirely lost; hence in spite of the open 

 I)upil the finger may be approached to the eye vritliout the animal 

 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 i^atient makes no effort to evade it. Sometimes the edges of 

 the contracted pui)il become adherent to each other by an intervening 

 plastic exudation, and the opening becomes virtuallj' abolished. In 

 severe inflammations pus maj' form in the choroid or iris, and escap- 

 ing into the cavity of the aqueous liumor 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), 

 Avhich 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 chambe]-, Avith 

 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 caj^sulc (capsular), while those that show a radiating 

 arrangement are in the lens (lenticular), the radiating fibers of which 

 the exudate follows. Black cataracts are formed by the adhesion of 

 the pigment on the back of the iris to the front of the lens, and by the 

 subsequent tearing loose of the iris, leaving a portion of its pigment 

 adherent to the capsule of the lens. If the pupil is so contracted that 

 it is impossible to see the lens, it may be dilated by applying to the 



