The medical aspects of the question have been studied especially by Schamberg and Goldberger and from the latter's summary (1910) we derive the following data. Within twelve to sixteen hours after exposure, itching appears and in severe cases, especially where exposure is continued night after night by sleeping on an infested bed, the itching may become almost intolerable. Simultaneously, there appears an eruption which characteristically consists of wheals surrounded by a vesicle (fig. 55). The vesicle as a rule does not exceed a pin head in size but may become as large as a pea. Its contents rapidly become turbid and in a few hours it is converted into a pustule. The eruption is most abundant on the trunk, slight on the face and extremities and almost absent on the feet and hands. In severe cases there may be constitutional disturbances marked, at the outset, by chilliness, nausea, and vomiting, followed for a few days by a slight elevation of temperature, with the appearance of albumin in the urine. In some cases the eruption may simulate that of chicken-pox or small-pox. Treatment for the purpose of killing the mites is hardly necessary as they attach feebly to the surface and are readily brushed off by friction of the clothes. "Antipruritic treatment is always called for; warm, mildly alkaline baths or some soothing ointment, such as zinc oxide will be found to fulfil this indication." Of course, reinfestation must be guarded against, by discarding, or thoroughly fumigating infested mattresses, or by avoiding other sources. Goldberger suggests that farm laborers who must work with infested wheat or straw might protect themselves by anointing the body freely with some bland oil or grease, followed by a change of clothes and bath as soon as their work is done. We are not aware of any experiments to determine the effect of flowers of sulphur, but their efficiency in the case of "red bugs" suggests that they are worth a trial against _Pediculoides_.