Kenny, thanks for the link to Dundee Cat! It seems to be basically the same song as The Corries' 'The Widow and the Fairy', credited to Fred Wedlock. (Should I post the lyrics for comparison?) I suppose Hamish (or maybe someone else) took and 'localised' it in time-honoured fashion. Or maybe not, for Hamish's recording is older than the Corries one I have.