and pounded several times upon the painted metal, as if to arouse the occupant, whatever it might be. A faint stench came from the aperture as the doctor unclosed it, and I fancied his pounding elicited a kind of low, hissing response. Finally he motioned me to replace him at the peep-hole, and I did so with a causeless and increasing tremor. The barred, ground-glass window, close to the earth outside, admitted only a feeble and uncertain pallor; and I had to look into the malodorous den for several seconds before I could see what was crawling and wriggling about on the straw-covered floor, emitting every now and then a weak and vacuous hiss. Then the shadowed outlines began to take shape, and I perceived that the squirming entity bore some remote resemblance to a human form laid flat on its belly. I clutched at the door-handle for support as I tried to keep from fainting. The moving object was almost of human size, and entirely devoid of clothing. It was absolutely hairless, and its tawny-looking back seemed subtly squamous in the dim, ghoulish light. Around the shoulders it was rather speckled and brownish, and the head was very curiously flat. As it looked up to hiss at me I saw that the beady little black eyes were damnably anthropoid, but I could not bear to study them long. They fastened themselves on me with a horrible persistence, so that I closed the panel gaspingly and left the creature to wriggle about unseen in its matted straw and spectral twilight. I must have reeled a bit, for I saw that the doctor was gently holding my arm as he guided me away. I was stuttering over and over again: "B-but for God's sake, what is it?" "B-but—for God's sake what is it?" Dr. McNeill told me the story in his private office as I sprawled opposite him in an easy-chair. The gold and crimson of late afternoon changed to the violet of early dusk, but still I sat awed and motionless. I resented every ring of the telephone and every whir of the buzzer, and I could have cursed the nurses and interns whose knocks now and then summoned the doctor briefly to the outer office. Night came, and I was glad my host switched on all the lights. Scientist though I was, my zeal for research was half forgotten amid such breathless ecstasies of fright as a small boy might feel when whispered witch-tales go the rounds of the chimney-corner. It seems that Yig, the snake-god of the central plains tribes—presumably the primal source of the more southerly Quetzalcoatl or Kukulcan—was an odd, half-anthropomorphic devil of highly arbitrary and