In strumous constitutions specks of the cornea are often accompanied with ulceration of the edges of the palpebræ, and destruction of the ciliæ—_the ophthalmia tarsi_. The margins of the eyelids are red and slightly tumid, and discharge an acrid fluid; the ciliæ are matted together; pustules form at their roots; the bags which secrete them are laid open and destroyed, and they consequently fall out. The affection is often of long duration, and may be in part prolonged by vitiated secretion from the meibomian glands. During its progress it excites very considerable irritation in the whole eye, and, as has been already stated, opacities of the cornea not unfrequently accompany it. Veins become enlarged, and varicose on the conjunctiva, as also their minute ramifications on the clear part of the ball; small reddish lines appear on the cornea, and around them is “diffused a thin, milky, or albuminous humour,” which destroys its transparency at that part. Such spots may be solitary or numerous, and darken the cornea either partially or entirely. They are always surrounded with a fasciculus of enlarged veins. In elderly people a dim opaque ring, of a greyish colour, sometimes encircles the margins of the cornea, and is called _Arcus Senilis_; but this can scarcely be looked upon as a disease. Sometimes the cornea presents a _spotted_ appearance; and this state of the organ is generally attended by obstinate inflammatory action in the part. The affection, however, is rare. I have seen several instances of it: in one, both corneæ were spotted, and sight was almost destroyed, without much irritability of the organ. The disease yielded to external stimulants, and the internal use of the bichloride of mercury. It is met with in a chronic and very intractable form. The cornea may sometimes be rendered dim by _over-distension_, the aqueous humour being unusually copious. Occasionally _sloughing_ takes place in the cornea from over-action. It is dangerous to the structure and functions of the organ, according to the extent to which it occurs. _Ossification_ of the cornea is said to take place; but few cases are on record, and these were in very old people. The cornea sometimes becomes _conical_ to a great degree in persons considerably advanced in life. The cone has its apex in the centre of the organ, seems thick and crystalline when viewed laterally, and when looked on from the front has a sparkling appearance. In some cases it is opaque in the centre, and occasionally its surface is irregular. Vision of objects at any distance is very indistinct; those placed within an inch or two of the eye are most distinctly seen, especially if looked on through a small aperture. The disease usually affects both eyes, though not always in an equal degree. The patients cannot judge accurately of distance, and see objects multiplied and disfigured. [Illustration]