2a. var. andrewsii
Pl. 419 a
Corolla lobes
reduced to an inconspicuous point 0.5–1.0 mm long. 2n=26.
August–October.
Uncommon and
widely scattered in eastern Missouri and disjunctly in Platte County
(northeastern U.S. west to North Dakota and Missouri; Canada). Ledges of bluffs
and upland prairies.