For 10 points, name this typeof supernatural being which is omitted from Rossini's opera version of Cinderella.
An opera in which one of these beings named Ada falls for a noble named Arindal was composed atWurzburg when its composer was only twenty. In a later operetta, a shepherd named Strephon is the son ofone of these beings, who come to dominate the British House of Lords. In an Italian opera, a male tutor namedAlidoro replaces one of these beings in the narrative. Gilbert and Sullivan's Iolanthe is titled for one of thesebeings, which also name the first completed opera by Richard Wagner. In an adaptation of Shakespeare byHenry Purcell, one of these beings sprinkles love-juice on the eyes of Demetrius. For 10 points, name this typeof supernatural being which is omitted from Rossini's opera version of Cinderella. 
An opera in which one of these beings named Ada falls for a noble named Arindal was composed atWurzburg when its composer was only twenty.
 fairy [or The Fairies; or Die Feen]