Canker of the ear is one of the forms of eczema. It consists of a discharge, at first brownish, which may afterward become mattery, from the inside of the external ear. If this continues, the delicate skin lining the ear becomes ulcerated and excessively painful. The cat scratches at its ear in attempting to relieve the pain, and produces wounds on the ear itself, which from constant rubbing and irritation become chronic ulcers.

The cause of eczema is a lymphatic condition in the constitution of the animal. Certain families are more lymphatic than others, and they are predisposed to it. Constant confinement in the house, want of exercise, and overfeeding are the principal exciting causes.

We also have, however, another form of eczema which is due to want of nutrition. This we sometimes find in young, half-grown kittens, or cats which have been badly nourished or almost starved.

The treatment of eczema is based, first, essentially, upon a strict attention to diet and regime. An over-fed cat must be starved - a poorly fed cat must be properly nourished. Diuretics and laxatives in the form of five-grain doses of Rochelle salts or Glauber's salts, and one-grain doses of iodide of potash can be combined with tonics. The best of the latter are quinine, Huxham's tincture, and syrup of wild cherry bark. Fowler's solution may be used in two-drop doses. Baths of sulphur water are beneficial. If there is much irritation an ointment of one part bitrine ointment and eight parts of lard is soothing and healing. In canker of the ear, iodoform as a powder, or mixed with balsam of Peru, can be dropped into the ear. Once a day the ear should be cleansed with a pleget of cotton on a match or small probe.