That 'Motif-Index' bit in Baughman's title rather scared me off his published book, which may actually be quite worthwhile. That motif business is sometimes nothing but a long list of euphemisms, e.g.:

Penis: pin, needle, pen, knife, dagger, rapier, sword, spear, lance, arrow, bow, canon, gun, rifle, bayonet, poker, and other tools of various types, etc.
Vagina; her black; black joke; ink well, 'xyz' hole; quiver, sheath, scabbard, purse, pin cushion, fiddle, portal, gates, fortress, keep (as opposed to breastworks), powder room, etc.

The chapter 'Toward a Motif-Index of Erotic Humour' in Legman's 'The Hornbook' provides several example of joke/song versions.
He noted there that Arne-Thompson assigned numbers X700-799 the title "Humour Concerning Sex", but left it blank.