The Tylwyth Teg have a fatal admiration for lovely children. Hence the abundant folk-lore concerning infants who have been stolen from their cradles, and a plentyn-newid (change-child--the equivalent of our changeling) left in its place by the Tylwyth Teg. The plentyn-newid has the exact appearance of the stolen infant, at first; but its aspect speedily alters. It grows ugly of face, shrivelled of form, ill-tempered, wailing, and generally frightful. It bites and strikes, and becomes a terror to the poor mother. Sometimes it is idiotic; but again it has a supernatural cunning, not only impossible in a mortal babe, but not even appertaining to the oldest heads, on other than fairy shoulders. The veracious Prophet Jones testifies to a case where he himself saw the plentyn-newid--an idiot left in the stead of a son of Edmund John William, of the Church Valley, Monmouthshire. Says Jones: 'I saw him myself. There was something diabolical in his aspect,' but especially in his motions. He 'made very disagreeable screaming sounds,' which used to frighten strangers greatly, but otherwise he was harmless. He was of a 'dark, tawny complexion.' He lived longer than such children usually lived in Wales in that day, (a not altogether pleasant intimation regarding the hard lot to which such children were subjected by their unwilling parents,) reaching the age of ten or twelve years. But the creed of ignorance everywhere as regards changelings is a very cruel one, and reminds us of the tests of the witchcraft trials. Under the pretence of proving whether the objectionable baby is a changeling or not, it is held on a shovel over the fire, or it is bathed in a solution of the fox-glove, which kills it; a case where this test was applied is said to have actually occurred in Carnarvonshire in 1857. That there is nothing specially Welsh in this, needs not to be pointed out. Apart from the fact that infanticide, like murder, is of no country, similar practices as to changelings have prevailed in most European lands, either to test the child's uncanny quality, or, that being admitted, to drive it away and thus compel the fairies to restore the missing infant. In Denmark the mother heats the oven, and places the changeling on the peel, pretending to put it in; or whips it severely with a rod; or throws it into the water. In Sweden they employ similar methods. In Ireland the hot shovel is used. With regard to a changeling which Martin Luther tells of in his 'Colloquia Mensalia,' the great reformer declared to the Prince of Anhalt, that if he were prince of that country he would 'venture _homicidium_ thereon, and would throw it into the River Moldaw.' He admonished the people to pray devoutly to God to take away the devil, which 'was done accordingly; and the second year after the changeling died.' It is hardly probable that the child was very well fed during the two years that this pious process was going on. Its starved ravenous appetite indeed is indicated in Luther's description: It 'would eat as much as two threshers, would laugh and be joyful when any evil happened in the house, but would cry and be very sad when all went well.'