The beautiful and fascinating Oengus is sometimes called Mac Ind Oc, “Son of the Young Ones,” i.e.  Dagda and Boand, or In Mac Oc, “The Young Son.”  This name, like the myth of his disinheriting his father, may point to his cult superseding that of Dagda.  If so, he may then have been affiliated to the older god, as was frequently done in parallel cases, e.g. in Babylon.  Oengus may thus have been the high god of some tribe who assumed supremacy, ousting the high god of another tribe, unless we suppose that Dagda was a pre-Celtic god with functions similar to those of Oengus, and that the Celts adopted his cult but gave that of Oengus a higher place.  In one myth the supremacy of Oengus is seen.  After the first battle of Mag-tured, Dagda is forced to become the slave of Bres, and is much annoyed by a lampooner who extorts the best pieces of his rations.  Following the advice of Oengus, he not only causes the lampooner’s death, but triumphs over the Fomorians.[285] On insufficient grounds, mainly because he was patron of Diarmaid, beloved of women, and because his kisses became birds which whispered love thoughts to youths and maidens, Oengus has been called the Eros of the Gaels.  More probably he was primarily a supreme god of growth, who occasionally suffered eclipse during the time of death in nature, like Tammuz and Adonis, and this may explain his absence from Mag-tured.  The beautiful story of his vision of a maiden with whom he fell violently in love contains too many Maerchen formulae to be of any mythological or religious value.  His mother Boand caused search to be made for her, but without avail.  At last she was discovered to be the daughter of a semi-divine lord of a sid, but only through the help of mortals was the secret of how she could be taken wrung from him.  She was a swan-maiden, and on a certain day only would Oengus obtain her.  Ultimately she became his wife.  The story is interesting because it shows how the gods occasionally required mortal aid.[286]

Equally influenced by Maerchen formulae is the story of Oengus and Etain.  Etain and Fuamnach were wives of Mider, but Fuamnach was jealous of Etain, and transformed her into an insect.  In this shape Oengus found her, and placed her in a glass grianan or bower filled with flowers, the perfume of which sustained her.  He carried the grianan with him wherever he went, but Fuamnach raised a magic wind which blew Etain away to the roof of Etair, a noble of Ulster.  She fell through a smoke-hole into a golden cup of wine, and was swallowed by Etair’s wife, of whom she was reborn.[287] Professor Rh[^y]s resolves all this into a sun and dawn myth.  Oengus is the sun, Etain the dawn, the grianan the expanse of the sky.[288] But the dawn does not grow stronger with the sun’s influence, as Etain did under that of Oengus.  At the sun’s appearance the dawn begins

    “to faint in the light of the sun she loves,
  To faint in his light and to die.”