... In the poems of Merddyn Wyllt there is a beautiful snowy-white magic-maiden, called, in Welsh, Chwyblian, or Vivlian, or Ganieda (which may be only the Canidia of Horace, used for a sorceress).  She dwells in forests and invites Merlin thither.  This Merlin finally departed in a ship of crystal, which is supposed to have been created by a blunder as to the figurative language of the Bards, who call death the crystal house... (History of Christian Names, Yonge, 1863)

... Rodarchus the Munificent, who reigned in Britain in the sixth century (A.D. 561), had two wives—one named Llangwrith, and the other Ganieda.  Merlin the Prophet was brother of Ganieda: he had accompanied Feredarus, General of the Venedati, when he made war on Guenolous, the King, and so also had Rodarchus, his brother-in-law, and is thus noticed in Geoffrey of Monmouth:—"Lo! then comes another from the hall of Rodarchus, King of the Cambri, to meet the conqueror, who had married Ganieda, and was happy in a beautiful wife.  She was the sister of Merlin.  And Rodarchus orders garments, hawks, hounds, swift steeds, gold, shining gems, and goblets, which Guierlaudus had carved in the city Sigeni, to be brought, and presents and offers them one by one to the prophet."  "We thus see," says Toland, translator of this passage, "that Merlin the Wild was no mean person.  His sister Ganieda was nobly married, and he himself, for his vaticination, which was a prominent part of the Druidical office, received a present which might have suited an emperor." (Lives of the Queens of England Before the Norman Conquest, Hall, 1864)