globes of quivering yellow flame, the black pupils being surrounded by a scintillating crimson light which threw out minute yellow sparks into the air. When I retired from the bird this preternatural fiery aspect would instantly vanish. The dragon eyes of that Magellanic owl haunt me till now, and when I remember them, the bird’s death still weighs on my conscience, albeit by killing it I bestowed on it that dusty immortality which is the portion of stuffed specimens in a museum. The question as to the cause of this fiery scintillating appearance is, doubtless, one very hard to answer, but it will force itself on the mind. When experimenting on the bird, I particularly noticed that every time I retired the nictitating membrane would immediately cover the eyes and obscure them for some time, as they will when an owl is confronted with strong sunlight; and this gave me the impression that the fiery, flashing appearance was accompanied with, or followed by, a burning or smarting sensation. I will here quote a very suggestive passage from a letter on this subject written to me by a gentleman of great attainments in science: “Eyes certainly do shine in the dark—some eyes, _e.g._ those of cats and owls; and the scintillation you speak of is probably another form of the phenomenon. It probably depends upon some extra-sensibility of the retina analogous to what exists in the molecular constitution of sulphide of calcium and other phosphorescent substances. The difficulty is in the _scintillation_. We know that light of this character has its source in the heat vibrations of molecules at the temperature of incandescence, and the electric light is no exception to the rule. A possible explanation is that supra-sensitive retinæ in times of excitement become increasedly phosphorescent, and the same excitement causes a change in the curvature of the lens, so that the light is focussed, and _pro tanto_ brightened into sparks. Seeing how little we know of natural forces, it may be that what we call light in such a case is eye speaking to eye—an emanation from the window of one brain into the window of another.”