"rounded r, is a historical calligraphic variant of the minuscule (lowercase) letter Latin r used in full script-like typefaces, especially blackletters.
Unlike other letter variants such as "long s" which originally were orthographically distinctive, r rotunda has always been a calligraphic variant, used when the letter r followed a letter with a rounded stroke towards the right side, such as o, b, p, h (and d in typefaces where this letter has no vertical stroke, as in ∂, ð) [and used when the letter r is double]." In: Wikipedia contributors. (2019, October 24). R rotunda. In Wikipedia, The Free Encyclopedia. Retrieved 10:50, December 30, 2019, from https://en.wikipedia.org/w/index.php?title=R_rotunda&oldid=922788180