The words are as given above by Snuffy.
The song is listed as traditional, arranged Timothy Hart,Peter knight,Frederick Kemp, Madelaine Prior & Robert Johnson (no further info given).

[A]
She showed me a cup of the good red gold
Well set with jewels so fair to see
Saying, "If you will be my lover so true
This goodly gift I would give to thee"

[B]
"Away, away, you ugly witch
Go far away and let me be
I never would kiss your ugly mouth
For all of the gifts that you could give"

[A]
She's turned her right and round about
And thrice she blew on a grass-green horn
She swore by the moon and the stars up above
That she'd make me rue the day I was born

[B]
Then out she has taken a silver wand
She's turned her three times round and round
She's muttered such words till my strength it did fail
And she's turned me into an ugly worm.

I've listed these verses again to show where they fit into the music.
There is a second voice given for part B that I have not included but if anyone want's it let me know.
KJ.