Cancrum oris, or Noma, is an affection of rare occurrence. It is met with in ill-nourished children, usually as a sequela of measles. The site of the disease is generally the cheek; in some instances the floor of the mouth or the gums are primarily involved. Soreness of the mouth, aggravated by the attempt to chew the food, and foetor of the breath, are usually the earliest symptoms; or the first thing noticed may be a swelling in one cheek, and on examination of the interior of the mouth a sloughing ulcer is discovered, and the neighbouring lymphatic glands are found to be enlarged. The gangrenous process rapidly extends, the discharge is exceedingly offensive, and the soft tissues are rapidly eaten away, and teeth may be loosened and the bone be exposed. In severe cases death may occur. In milder forms of the disease the patient escapes with more or less deformity as the result of cicatricial contraction.