I was reading a review of an urban fantasy book Broken Homes by Ben Aaronovitch, and one of the characters was described as:
"Professor Harold Postmartin, a Doctor of Philosophy (PhD), a Fellow of the Royal Society (FRS), and B.Mon, is the Folly’s chief (and only) archivist."
What does "B. Mon" mean? Seems to be some kind of a degree, but I haven't ever heard that abbreviation before. Google was unhelpful.