The map which occupies a single open page was originally described on Yale University’s “bibliotecapleyades” site as folio 86v.
This seems to have been a simple and sensible description for it.
The Beinecke Library site now describes the diagram as “folio 85v and 86r”
This will mean some inconvenience for followers of this blog; I’ll have to add a note to every post written using the original foliation.
For the sake of consistency, any future posts will still refer to the map as “folio 86v” in headings, but the later foliation will be referenced in in square brackets after the first mention in the body of text.