e furrows to
cleanse the iron of the plough.[389] Here he is brought into connection
with the plough, but the myth to which the words refer is lost. A
_Taliesin_ poem associates him with Math--"I have been with artificers,
with the old Math and with Govannon," and refers to his _Caer_ or
castle.[390]

Arianrhod, "silver wheel," has a twofold character. She pretends to be a
virgin, and disclaims all knowledge of her son Llew, yet she is mistress
of Gwydion. In the _Triads_ she appears as one of the three blessed (or
white) ladies of Britain.[391] Perhaps these two aspects of her
character may point to a divergence between religion and mythology, the
cult of a virgin goddess of whom myth told discreditable things. More
likely she was an old Earth-goddess, at once a virgin and a fruitful
mother, like Artemis, the virgin goddess, yet neither chaste nor fair,
or like a Babylonian goddess addressed as at once "mother, wife, and
maid." Arianrhod, "beauty famed beyond summer's dawn," is mentioned in a
_Taliesin_ poem, and she was later associated with the constellation
Corona Borealis.[392] Possibly her real name was forgotten, and that of
Arianrhod derived from a place-name, "Caer Arianrhod," associated with
her. The interpretation which makes her a dawn goddess, mother of light,
Lleu, and darkness, Dylan, is far from obvious.[393] Dylan, after his
baptism, rushed into the sea, the nature of which became his. No wave
ever broke under him; he swam like a fish; and hence was called Dylan
Eil Ton or "son of the wave." Govannon, his uncle, slew him, an incident
interpreted as the defeat of darkness, which "hies away to lurk in the
sea." Dylan, however, has no dark traits and is described as a blonde.
The waves lament his death, and, as they dash against the shore, seek to
avenge it. His grave is "where the wave makes a sullen sound," but
popular belief identifies him with the waves, and their noise as they
press into the Conway is his dying groan. Not only is he _Eil Ton_, "son
of the wave," but also _Eil Mor_, "son of the sea."[394] He is thus a
local sea-god, and like Manannan identified with the waves, and yet
separate from them, since they mourn his death. The _Mabinogi_ gives us
the _debris_ of myths explaining how an anthropomorphic sea-god was
connected with the goddess Arianrhod and slain by a god Govannon.

Another _Mabinogion_ group is that of Pwyll, prince of Dyved, his wife
Rhiannon, and their son Pryderi.[395] Pwyll