The Nixie of the Mill Pond is a German fairy tale that tells the story of a man captured by a nixie (water spirit) and his wife's efforts to save him. The Brothers Grimm collected the tale in their Grimm's Fairy Tales (1857) as tale number 181. A note in the volume indicated that it was current in Upper Lusatia when the story was collected. Andrew Lang included a version in The Yellow Fairy Book, citing his source Hermann Kletke and titling it The Nixy. It is classified as Aarne-Thompson Type 316, "The Nixie of the Mill Pond". This fairy tale type that falls under the larger category of "Supernatural Adversaries" and is characterized by a hero's parents being promised wealth or gifts in exchange for their child. This tale type is most common in Northern Europe and some variants have been recorded in Scotland.