An interesting and significant group of cases is furnished by those dreams in which--as the result of some compression or effort--the tactile and muscular sensations of our own limbs are split off from sleeping consciousness and built up into an imaginary personality. Thus a medical friend, shortly after an attack of influenza, dreamed that in conversation with a lady patient his hand rested on her knee; she requested him to remove it, but his efforts to do so were fruitless, and he awoke in horror from this unprofessional situation to find that his hand was firmly clasped between his own knees. His body had thus been divided in dreaming consciousness between himself and an imaginary other person; the knee had become the other person's, while the hand remained his own, the hand being claimed in preference to the knee no doubt on account of its greater tactile sensibility and more complexly intimate association with the brain. In the hypnagogic (or hypnopompic) state such dream sensations may almost reach the intensity of hallucination. Thus, after an indigestible supper, I awake with the vivid feeling that some one is lying on me and attempting to drag off the bedclothes, and I find myself violently attempting, but apparently in vain, to articulate: 'Who is there?' In a dream of similar type, which occurred when lying on my back (and possibly with slight indigestion due to an unusually late dinner), I awoke making a kind of inarticulate exclamation which awakened my wife. I had dreamed that I was lying in bed, and that some unseen creature--more supernatural than human, it seemed--was violently dragging the bedclothes off me, while I shouted to it, very distinctly it seemed to me, 'Avaunt, avaunt!' It is evident that my own sense of oppression, my own unconscious and involuntary movements in disturbing the bedclothes, were reconstructed by sleeping consciousness as the actions of an external person, in the second case, a supernatural creature, which, it is interesting to note, I duly accepted as such and addressed in the conventionally appropriate manner of old romance. The illusion may persist for some moments after waking. A lady, after breathing rather loudly and convulsively for a few seconds, wakes up, saying 'There is a rat or a mouse on the bed, shaking it up and down.' 'You were asleep,' her husband replied, 'as I knew by your breathing.' 'Oh, I was breathing like that,' she said, 'to make it jump off.' Here we see that, somewhat as in the previous cases, the dreamer's own muscular activity is, during sleep, reconstructed into the image of an external force; but when she is in the semi-waking hypnagogic stage, she recognises that the activity was her own, though still unable to dismiss the delusion based on the theory formed during sleep.