Cornu
In the Irish legend, this is a monstrous blackbird that was banished by St Patrick to the waters of Lough Berg to live upon a miserable and penitential island. This island was known as St Patrick’s Purgatory were hundreds of pilgrims come to the island every year to pray outside in the rain. They endure the colds winds and undergo a complete fast in order to purge their sins
John and Caitlin Matthews, The Element Encyclopaedia of Magical Creatures, 2013, Cornu, p 109
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