It has not been given to many of those whom I have the privilege of addressing to watch the course of the scientific investigation of the pathology of the psychoses for a period of thirty-four years. Many of my hearers are scarcely old enough to feel the pangs of dis appointment. It will be some twenty-five years ago that, in general, the attention of workers in the domain of the pathology of insanity began to slacken in respect of that aspect of the work which, till then, had mainly interested them, viz., the morbid anatomy of the brain. The output of work in this field about then showed signs of diminishing. Attention began to be directed to the problem of pathological causation. Search began to be made for the pathological factors which expressed themselves in the morbid histological conditions found in the brain-cortex, and, passing on, if we note the interests of young graduates studying for a diploma in psychological medicine, we shall, I think, find that they are not in the direction of histo-pathology, but rather in that of, for example, the function of the endocrines, of the autonomic nervous system, possibly of bio-chemistry. My experience of published work from foreign clinics in psychiatry is that the same drift from histology is noticeable. Nevertheless, it would be unphilosophical to take the view that research in morbid histology of the brain is not worth while, and a perusal of the literature shows the work in progress in the field of the normal histology of the nervous system. Improvements in technique—in the main due to German, Spanish and Italian workers (how comes it that this branch is so little cultivated by the British?)—will add to our knowledge, and thus research in morbid histology will be constantly stimulated.