The
Glain Neidr or
Maen Magi of
Welsh folklore is also closely connected to
Druidism. The
Glain Neidr of Wales are believed to be created by a congress of snakes, normally occurring in spring, but most auspicious on May Eve. Although not named as Glain Neidr, magic stones with the properties of adder stones appear frequently in
Welsh mythology and folklore. The
Mabinogion, translated into English in the mid-nineteenth century by
Lady Charlotte Guest, mentions such stones on two occasions. In the story of
Peredur son of Efrawg (
Percival of the
Arthurian cycle), in a departure from
Chrétien de Troyes'
Perceval, the Story of the Grail, Peredur is given a magical stone that allows him to see and kill an invisible creature called the
Addanc. In another tale,
Owain, or the Lady of the Fountain (Ywain of Arthurian legend), the hero
Owain mab Urien is trapped in the gatehouse of a castle. He is given a stone by a maiden, which turns
Owain invisible, allowing him to escape capture. == In Russian mythology ==