=Mental Examination.= On entrance to hospital patient seemed slightly depressed and a bit irritable. This condition lasted two days, after which he was agreeable and apparently entirely over his depression. Even during his mild depression, however, he talked freely. There was no evidence of retardation. He told his story readily. Orientation was intact. Memory excellent. Educational knowledge well retained. There was no evidence of any hallucinations or delusions. 1. Was Richard Lawlor insane? There was, then, on the mental and physical examination nothing to make a definite suggestion of a psychosis, and the most one could think of was a psychoneurosis or a cyclothymia of at least ten years’ duration. The findings in the cerebrospinal fluid and the Wassermann reactions, however, give us material for thought. Certainly one cannot call the man insane; all who saw him agreed on this point. 2. If Richard Lawlor should some day develop mental symptoms, what would be the genesis of the new psychosis? Though writers such as Fildes and McIntosh, and Swift, have suggested an anaphylactic or hyperallergic explanation for the development of symptoms after a normal interval; such a hypothesis could hardly obtain in the present case. The hyperallergic hypothesis for the development of tertiary neurosyphilis would run to the effect that in the secondary stages there had been a definite disease of the nervous system, which, however, absolutely cleared up, leaving no inflammatory vascular or parenchymatous relics of its existence. Nothing would on this hypothesis remain except a hypersensitisation of the tissues. In some later period of the now clinically normal person, one or more spirochetes from a lesion outside the nervous system are carried into the nerve tissues and there set up an anaphylactic or hyperallergic reaction. It is obviously difficult to prove the correctness or incorrectness of the hyperallergic theory without numerous examinations of the spinal fluid, in clinically normal persons after the secondaries have passed. The present case, so far from demonstrating a normal fluid, demonstrates a highly pathological fluid, even though there are absolutely no clinical symptoms which could be regarded as of nervous origin. The burden of proof at the present time would seem to lie with those who claim hyperallergy in neurosyphilis. We prefer on present evidence to think that at the conclusion of the secondaries a disease process often remains in the nerve tissues despite clinical quiescence.