pre-12th century—present. Old Irish | Modern Irish, folklore.
Ex(change) of identity Birds and animals again and again
They suddenly lose sight of the deer, as though it has vanished into the ground. A short while later, the animal reappears as a beautiful young maiden sitting beside a lake.
Fionn is at home once when he sees a grey deer; it comes close by and then makes off into the woodland. Calling to all his men to give chase, only his two trusted dogs Bran and Sceolan follow him in pursuit. They chase the deer all the way to Slieve Cuilinn in the north, but here they suddenly lose sight of the animal, as though it has vanished into the ground. A short while later, the animal reappears as a beautiful young maiden sitting beside a lake.
Story fragment recounted from: Gregory, Lady A., 1904. Gods and Fighting Men: The Story of the Tuatha de Danaan and of the Fianna of Ireland, Arranged and put into English by Lady Gregory. John Murray, London. Reprinted, 1998. Irish Myths and Legends. Running Press Book Publishers, Philadelphia, USA. Part Two: The Fianna. Book IV: Huntings and Enchantments. Chapter 15: The Hunt of Slieve Cuilinn, pp 288–291.
Tuatha de Danaan - Wikipedia
Fionn mac Cumhaill - Wikipedia
Gods and Fighting Men – ancient tales of Ireland put into English by Lady Augusta Gregory. 1904. Project Gutenberg.