This disease is also caused by a vegetable parasite and is contagious. It usually begins in childhood and is most often seen among the poor. It is but seldom seen among native Americans, but is rather frequent among natives of Russia, Poland, and Italy. The favus parasite attacks the scalp most often, and the nails and body comparatively seldom.

Favus of the Scalp.—The characteristic feature of this affection is the presence of tiny yellowish crusts, usually with a hair in the center. The typical eruptions of favus are about the size of a split pea, rounded, hollowed-out in the center, of sulphur-yellow color and with a hair passing through the center. The material entering into the make-up of the crusts falls apart, like dry mortar, when taken between the fingers. When the cup-shaped masses are removed, a reddened, pus-containing cavity is exposed. Finally, when healing takes place, a thin, paper-like scar forms, with almost complete baldness of the affected parts, excepting for a few tufts of hair here and there. Sometimes the individual crusts join with others and large patches covering almost the entire scalp may thus be formed. In advanced cases, a peculiar mouselike odor may be present, which is quite characteristic of this disease. The hairs of the affected areas are dry, dull-looking, brittle and apt to break off and fall out. Some degree of itching is present in most cases.

Contagiousness of Favus.—This malady is but slightly contagious as compared with ringworm. Favus spreads, as a rule, through direct contact, although it may be carried by rats, cats, mice, cattle, and horses.

Suggestions for Prevention and Treatment.—Though favus is but mildly contagious, nevertheless, all the precautions recommended for the pre. vention of the spread of ringworm should also be observed here. The hair should be kept closely cut. The crusts may be removed by softening with either sweet oil or olive oil and the scalp washed with soap and water. The treatment of favus requires the services of a dermatologist.