4th. =Determine the vascularity of the conjunctiva.= When free from pigment as it habitually is in pigs and birds this is easily done, while in animals like the horse, in which the bulbar portion, which covers the sclerotic, is largely pigmented, we can scrutinize only the pigment free parts. =In health= there should be only a few, fine, pink vessels which move with the mucosa when pressed aside on the bulb. =In congestion= the surface may appear brick red, and the vessels are irregular, large, tortuous and are seen to anastomose at frequent intervals. These move on the bulb when pressed. The congestion is usually deepest on the palpebral mucosa and in the _cul de sac_, and may be whitened for an instant by pressure through the eyelid. To expose the conjunctiva the right fore finger and thumb may be pressed on the upper and lower lids respectively of the left eye, and the left finger and thumb for the right, allowing them to slide backward above and below the eyeball. Another method is to seize the cilia and edge of the upper eyelid between the finger and thumb, and draw it downward and outward from the bulb, and then deftly invert it over the tip of the finger. In the old the unpigmented conjunctiva may appear yellow from the presence of subconjunctival fat, or this may appear at any age from hepatic disease (distomatosis) or icterus. It is swollen, or dropsical in anæmia, distomatosis, etc. 5th. =Examine the ciliary vessels whether they are congested or not.= These are distinguished from the conjunctival vessels in that they radiate in straight lines outward from the margin of the transparent cornea and do not move on the sclerotic under pressure. They are enlarged and very red in congestion of the ciliary circle and in iritis. In eyes devoid of pigment over the sclerotic, there is usually a circular, narrow, white zone between the congested area and the margin of the transparent cornea. 6th. =Examine the Membrana Nictitans.= See that its free margin is uniformly smooth, even, and thin and that there is no swelling, congestion nor morbid growth on any part of the structure. 7th. =See if the transparent cornea is perfectly and uniformly smooth, transparent and glistening and if it reflects clear, erect images of all objects in front of it.= The image of a round object which shows any irregularity in the curvature of its margin implies a deviation from an uniform curvature of the cornea: the image narrows in the direction of the smaller arc and broadens in the direction of the larger one (see keratoscopy, and corneal astigmatism). 8th. =A foreign body on or in the cornea= may be recognized in a good light, but better and more certainly under focal oblique illumination (see this heading).