Fastitocalon (poem)
From Tolkien Gateway
"Fastitocalon" is a poem by J.R.R. Tolkien published in The Adventures of Tom Bombadil.[1] This poem is a revised version of the poem "Adventures in Unnatural History and Medieval Metres, being the Freaks of Fisiologus".
The central character is Fastitocalon, the last of the Turtle-fish. The setting is Middle-earth.