Speaking generally, the Celtic heroes are differentiated from the Teutonic by the extreme exaggeration of their superhuman, or rather extra-human, qualities. Teutonic legend does not lightly exaggerate, and what to us seems incredible in it may be easily conceived as credible to those by whom and for whom the tales were told; that Sigmund and his son Sinfiotli turned themselves into wolves would be but a sign of exceptional powers to those who believed in werewolves; Fafnir assuming the form of a serpent would be no more incredible to the barbarous Teuton than the similar transformation of Proteus to the Greek. But in the characterization of their heroes the Celtic imagination runs riot, and the quality of their persons and their acts becomes exaggerated beyond the bounds of any conceivable probability. Take, for instance, the description of some of Arthur's knights in the Welsh tale of _Kilhwch and Olwen_ (in the _Mabinogion_). Along with Kai and Bedwyr (Bedivere), Peredur (Perceval), Gwalchmai (Gawain), and many others, we have such figures as Sgilti Yscandroed, whose way through the wood lay along the tops of the trees, and whose tread was so light that no blade of grass bent beneath his weight; Sol, who could stand all day upon one leg; Sugyn the son of Sugnedydd, who was "broad-chested" to such a degree that he could suck up the sea on which were three hundred ships and leave nothing but dry land; Gweyyl, the son of Gwestad, who when he was sad would let one of his lips drop beneath his waist and turn up the other like a cap over his head; and Uchtry Varyf Draws, who spread his red untrimmed beard over the eight-and-forty rafters of Arthur's hall. Such figures as these make no human impression, and criticism has busied itself in tracing them to one or other of the shadowy divinities of the Celtic pantheon. However this may be, remnants of their primitive superhuman qualities cling to the Celtic heroes long after they have been transfigured, under the influence of Christianity and chivalry, into the heroes of the medieval Arthurian romance, types--for the most part--of the knightly virtues as these were conceived by the middle ages; while shadowy memories of early myths live on, strangely disguised, in certain of the episodes repeated uncritically by the medieval poets. So Merlin preserves his diabolic origin; Arthur his mystic coming and his mystic passing; while Gawain, and after him Lancelot, journey across the river, as the Irish hero Bran had done before them to the island of fair women--the Celtic vision of the realm of death.