There are lots of maggots in Playford and music of similar era, I think its supposed to mean "favourite", but I've come across no explanation of the word's origin. I like to think of the tunes as nuggets. Magpies used to be called maggoty pies didn't they? Mr Isaacs maggot was on an accordion compilation I got hold of recently, and immediately learned it -it is a good tune. If you're into that sort of music get hold of the old John Kirkpatrick&Sue Harris LPs and check out John Clare's music ms. especially the Woodpecker!!