This is known mostly from the "Driftless Area" of sw. Wisc. and adjacent states, but there are also scattered reports from Mo., Ky., W.Va. and Pa. (F, Cr, PL). Records from W.Va. are based on meadia, according to FNA 8. The only potential Ky. record is a coll. at GH with little data: Lesquereaux s.n., "Kentucky near the Ohio River"; det. N.C. Fassett (F, M). The identity and context of that coll. needs further study. Distinction of amethystinum from frenchii and meadia has been based simply on its capsules, which have thinner walls when fully mature ("pliable" versus "rigid"), and tend to be lighter reddish brown to yellowish (versus dark reddish brown). It is restricted to relatively mesic sites, usually below calcareous cliffs.