Pierides. In Greek mythology, the Pierides or Emathides were the nine sisters who defied the Muses in a contest of song and, having been defeated, were turned into birds.
The Muses themselves are sometimes called by this name. They were the daughters of Pierus, king of Emathia in Macedon, by Antiope of Pieria or Euippe of Paionia.
The sisters were also called Emathides, named after their paternal uncle Emathus. In Ovid's Metamorphoses, Urania, one of the Muses recounts their contest with the Pierides to Athena in the following excerpts: So spoke the Muse.
And now was heard the sound of pennons in the air, and voices, too, gave salutations from the lofty trees. Minerva, thinking they were human tongues, looked up in question whence the perfect words; but on the boughs, nine ugly magpies perched, those mockers of all sounds, which now complained their hapless fate.
And as she wondering stood, Urania, goddess of the Muse, rejoined;, Look, those but lately worsted in dispute augment the number of unnumbered birds., Pierus was their father, very rich in lands of Pella; and their mother when she brought them forth, nine times evoked, in labours nine, Lucina's aid., Unduly puffed with pride, because it chanced their number equaled ours these stupid sisters, hither to engage in wordy contest, fared through many towns;, through all Haemonia and Achaia came to us, and said; Oh, cease your empty so