PEMPHIGUS vulgaris is a constitutional disease whose most obvious and diagnostic manifestations are in the skin, thus resembling the exanthems. In recent years the etiologic agent has been thought to be a virus, and reports have already been made1 of the isolation of strains in 4 cases of the disease. The relation of the strains to pemphigus vulgaris had not been established when the reports appeared, but subsequent data, now in preparation for publication,2 indicate that the RP strain of virus is the etiologic agent of the disease. It was accordingly felt that antibodies which would neutralize the virus would be present in the blood serum of persons who had recovered from the disease. Owing to the high mortality and relative rarity of occurrence of pemphigus vulgaris, such persons are few in number and difficult to find. In response to nation-wide appeals, however, 2 women