In a previous communication concerned with this subject,1 attention was directed to the importance of this question and its thorough investigation was urged.There are few laboratories in which cholesterinized antigens do not play some part in the serologic diagnosis of syphilis, either forming a part of a multiple antigen battery or even constituting the sole standard by which the positiveness of the reaction is to be gaged.As noted elsewhere,2 the problem is one well worthy of, and even compelling, the attention of both serologist and clinician, for its satisfactory solution depends not on either alone but on the combined efforts of both.