Ringworm in the cat appears in the form of little round spots from the size of a ten-cent piece to the size of a quarter-dollar. Sometimes the various spots run into each other and form irregular-shaped spots, the edges of which, however, always assume the rounded form. In these spots the hairs are broken off, leaving little bristling points only protruding from the roots. The surface of the skin itself is covered by a furfuraceous scab, which, if peeled or rubbed off, shows a slight exudation below. If not attended to, the disease keeps spreading to new parts of the body as fast as the older spots heal. Ringworm is due to a vegetable parasite known as Trichophyton tonsurans. The cat is probably one of the most common sources of the propagation of this disease to the human being, especially children. The cat in turn probably, in the majority of cases, contracts the disease, not from others of its own kind, but from sewer-rats which are caught as prey.

Some years ago, while I had charge of the dispensary of the Children's Hospital at Philadelphia, I collected a large number of statistics in regard to the children who came to the hospital with ringworm. They, of course, represented the poorer classes. Invariably I found that the patients had in the house a cat which they played with: and I verified the origin by examining their cats and finding them affected with the disease. A cat with ringworm should be isolated for a few days from the children and from other cats, until the spots have been well rubbed with mercurial ointment for several days in succession. Then the animal should be watched daily for the next week or two for the appearance of fresh spots, which should be treated with mercurial ointment the instant they appear.