A person infected with a specific organism is in a state of hypersensitivity to that organism as long as it remains in the body. The reaction of the skin to gonococcus toxin in persons infected with the gonococcus is a manifestation of allergy the exact nature of which is not known at present beyond the fact that it is a local tissue response between antigen and antibody. That this reaction denotes clinical specificity may be demonstrated by the passive transfer or Prausnitz-Küstner reaction first demonstrated in gonorrhea by Engel and Vigliani1in 1935. In a preliminary report a little later, the senior author also called attention to this proof of clinical specificity. As early as 1909 Bruck2called attention to the fact that persons infected with the gonococcus showed an allergic reaction to the cutaneous application of killed gonococci similar to that shown by tuberculous persons to the