.[364] In later belief Don was associated with the
stars, the constellation Cassiopeia being called her court. She is
described as "wise" in a _Taliesin_ poem.[365]

This group of divinities is met with mainly in the _Mabinogi_ of Math,
which turns upon Gilvaethwy's illicit love of Math's "foot-holder"
Goewin. To assist him in his _amour_, Gwydion, by a magical trick,
procures for Math from the court of Pryderi certain swine sent him by
Arawn, king of Annwfn. In the battle which follows when the trick is
discovered, Gwydion slays Pryderi by enchantment. Math now discovers
that Gilvaethwy has seduced Goewin, and transforms him and Gwydion
successively into deer, swine, and wolves. Restored to human form,
Gwydion proposes that Arianrhod should be Math's foot-holder, but Math
by a magic test discovers that she is not a virgin. She bears two sons,
Dylan, fostered by Math, and another whom Gwydion nurtures and for whom
he afterwards by a trick obtains a name from Arianrhod, who had sworn
never to name him. The name is Llew Llaw Gyffes, "Lion of the Sure
Hand." By magic, Math and Gwydion form a wife for Llew out of flowers.
She is called Blodeuwedd, and later, at the instigation of a lover,
Gronw, she discovers how Llew can be killed. Gronw attacks and wounds
him, and he flies off as an eagle. Gwydion seeks for Llew, discovers
him, and retransforms him to human shape. Then he changes Blodeuwedd
into an owl, and slays Gronw.[366] Several independent tales have gone
to the formation of this _Mabinogi_, but we are concerned here merely
with the light it may throw on the divine characters who figure in it.

Math or Math Hen, "the Ancient,"[367] is probably an old divinity of
Gwyned, of which he is called lord. He is a king and a magician,
pre-eminent in wizardry, which he teaches to Gwydion, and in a _Triad_
he is called one of the great men of magic and metamorphosis of
Britain.[368] More important are his traits of goodness to the
suffering, and justice with no trace of vengeance to the wrong-doer.
Whether these are derived from his character as a god or from the Celtic
kingly ideal, it is impossible to say, though the former is by no means
unlikely. Possibly his supreme magical powers make him the equivalent of
the Irish "god of Druidism," but this is uncertain, since all gods were
more or less dowered with these.

Gwydion's magical powers are abundantly illustrated in the tale. At
Pryderi's court he changes fungus into hors