Jim- I also came up with that stanza but it's of course another song. If you add an 8. to "A voice they did hear." and hit search in snippet view or google books you'll see that there's an 8th stanza- plus it makes sense that there is.
Steve- Yes I know there are lots of version of Pretty Polly that are not CSC- these are a blending of texts from Pretty Polly found in other 3/4 time songs- so they are actually hybrid versions and not other songs about a girl named Pretty Polly. The melody is the other song. So this is not significant but shows the Pretty Polly text crossed over into other 3/4 time songs.
What may be important is the AAB form as a pre-blues format, since obviously Pretty Polly predates the birth of the blues. In Appalachia these are know as "white blues" that are modal, pentatonic with a flat 7 and sometimes minor 3rd (sung). They sometimes shift to a flat 7 chord with a progression something like: I VIIb7 I I VIIb7 I V7 I. Examples include Hustling Gamblers, Little Maggie, and Darling Cory.
TY tradsinger- for that version similar to the text of the broadside "Polly's love" from Wiggy Smith- what a singer!!!