During recent years, the methods of research in the treatment for paresis as a syphilitic disease of the central nervous system have been associated with concomitant studies on the serology and pathologic histology of this disease with two main purposes in view: (1) to determine the mode of action of the different therapeutic agents, and (2) to establish some tangible guides of prognostic value. For the latter purpose, the different methods of examination of the blood and cerebrospinal fluid seemed to promise particularly good results. If the serologic tests would prove as valuable guides to the progress in cases under treatment as they did as aids in differentiating some neurosyphilitic diseases from others and neurosyphilis as a group from other organic diseases, one would have definite criteria for the management of each case under treatment. The advent of the malarial and allied nonspecific methods of therapy has given a new