incantation, to
destroy all the people of the serpent race. To prevent this
annihilation, the supernatural being, Pundarika Nag, took a human
form, and became the husband of the beautiful Parvati, daughter of a
Brahman. But Pundarika Nag, being a serpent by nature, could not
divest himself, even in human shape, of his forked tongue and venomed
breath. And, just as Urvasi could not abide with her mortal lover,
after he transgressed the prohibition to appear before her naked, so
Pundarika Nag was compelled by fate to leave his bride, if she asked
him any questions about his disagreeable peculiarities. She did, at
last, ask questions, in circumstances which made Pundarika believe
that he was bound to answer her. Now the curse came upon him, he
plunged into a pool, like the beaver, and vanished. His wife became
the mother of the serpent Rajas of Chutia Nagpur. Pundarika Nag, in
his proper form as a great hooded snake, guarded his first-born child.
The crest of the house is a hooded snake with human face.[81]

Here, then, we have many examples of the disappearance of the bride or
bridegroom in consequence of infringement of various mystic rules.
Sometimes the beloved one is seen when he or she should not be seen.
Sometimes, as in a Maori story, the bride vanishes merely because she
is in a bad temper.[82] Among the Red Men, as in Sanskrit, the taboo
on water is broken, with the usual results. Now for an example in
which the rule against using _names_ is infringed.[83]

This formula constantly occurs in the Welsh fairy tales published by
Professor Rhys.[84] Thus the heir of Corwrion fell in love with a
fairy: 'They were married on the distinct understanding that the
husband was not to know her name, ... and was not to strike her with
iron, on pain of her leaving him at once.' Unluckily the man once
tossed her a bridle, the iron bit touched the wife, and 'she at once
flew through the air, and plunged headlong into Corwrion Lake.'

A number of tales turning on the same incident are published in
_Cymmrodor_, v. i. In these we have either the taboo on the name, or
the taboo on the touch of iron. In a widely diffused superstition iron
'drives away devils and ghosts,' according to the Scholiast on the
eleventh book of the _Odyssey_, and the Oriental Djinn also flee from
iron.[85] Just as water is fatal to the Aryan frog-bride and to the
Red Indian beaver-wife, restoring them to their old animal forms, so
the magic touch of iron