The following case is placed on record as it is an excellent example of a type of special disturbances of vision which claim our interest, not only on account of their relative rarity, but chiefly because they throw considerable light on the functions and modes of activity of the cerebral cortex, and particularly on those processes which are concerned in the integration and association of sensations.
The case is described at length as the patient exhibited many symptoms which could be fully understood only when carefully studied and analyzed. We were particularly fortunate in that he was an intelligent, willing and objective witness, and had no disturbances of speech, or motor or sensory symptoms that could complicate our observations. On the other hand, we have made our discussion of his condition as concise as possible with due regard to clearness, more especially as one of us has recently recorded six