The Gwyllgi finds its counterpart in the Mauthe Doog of the Isle of Man and the Shock of the Norfolk coast. It there comes up out of the sea and travels about in the lanes at night. To meet it is a sign of trouble and death. The Gwyllgi also is confined to sea-coast parishes mainly, and although not classed among death-omens, to look on it is deemed dangerous. The hunting dogs, Cwn Annwn, or dogs of hell, whose habitat is the sky overhead, have also other attributes which distinguish them clearly from the Gwyllgi. They are death-omens, ancient of lineage and still encountered. The Gwyllgi, while suggesting some interesting comparisons with the old mythology, appears to have lost vogue since smuggling ceased to be profitable. VI. Confined to the coast, too, are those stories of phantom ships and phantom islands which, too familiar to merit illustration here, have their origin in the mirage. That they also touch the ancient mythology is undoubted; but their source in the mirage is probably true of the primeval belief as well as of the medieval, and that of our time. The Chinese also have the mirage, but not its scientific explanation, and hence of course their belief in its supernatural character is undisturbed. CHAPTER IV. Grotesque Ghosts--The Phantom Horseman--Gigantic Spirits--The Black Ghost of Ffynon yr Yspryd--Black Men in the Mabinogion--Whirling Ghosts--Antic Spirits--The Tridoll Valley Ghost--Resemblance to Modern Spiritualistic Performances--Household Fairies. I.