=Physically=, he was a powerfully-built man and in very good physical condition except for an iritis and moderate thickening of the peripheral arteries. The =neurological signs= of importance were Argyll-Robertson pupils, and absent knee-jerks and ankle-jerks. With these findings in mind, a tentative diagnosis of GENERAL PARESIS was made, and this was substantiated by the laboratory tests, which gave positive W. R.’s in blood and spinal fluid, globulin, excessive albumin, slight pleocytosis, and a “paretic” gold sol reaction. When the patient’s mental condition was somewhat better, he gave a history of syphilitic infection 15 years before, for which he had had almost continuous treatment. As a matter of fact, treatment had been pretty strenuous because he had recurring skin lesions and iritis. It was practically impossible to get the skin lesions to heal with mercury, and it was not until salvarsan was introduced that a good result was obtained in this respect. After one or two injections of this drug, the skin lesion disappeared and has never returned. However, at least once a year, he has had attacks of iritis, and for this reason was still being treated for syphilis at the outbreak of his psychosis. He was at once placed on more strenuous antisyphilitic treatment in the form of diarsenol, semi-weekly, aided by mercury injections. After a few months of this treatment, his mental condition improved so much that he seemed to be entirely normal. Treatment was continued, however, without any abatement, and it was of great interest to note at the end of five months of such treatment that, although mentally he seemed entirely well, he had an attack of iritis, which was considered as a sign of active syphilis. This would appear to indicate the great difficulty of getting results in certain cases of syphilis with any drugs at our command at present, as in the iritis we are dealing with a condition which as a rule reacts fairly readily to antisyphilitic remedies. 1. Are there different strains of spirochetes showing various degrees of malignancy? This question has been discussed at length in the literature but there is no satisfactory answer at the present time. We must always consider the reaction of the organism and the host; and it is true in syphilis, as in every other disease, that in some individuals it is more difficult to get any therapeutic results than in others.