American Harebell, Bluebell Bellflower, Bluebell-of-Scotland, Roundleaf Bluebell, Scots Bellflower: Campanula rotundifolia (Synonyms: Campanula alaskana, Campanula dubia, Campanula gieseckiana, Campanula gieseckiana ssp. groenlandica, Campanula gieseckiana var. arctica, Campanula groenlandica, Campanula heterodoxa, Campanula intercedens, Campanula petiolata, Campanula rotundifolia ssp. groenlandica, Campanula rotundifolia ssp. intercedens, Campanula rotundifolia var. alaskana, Campanula rotundifolia var. alpina, Campanula rotundifolia var. arctica, Campanula rotundifolia var. intercedens, Campanula rotundifolia var. lancifolia, Campanula rotundifolia var. petiolata, Campanula rotundifolia var. velutina, Campanula sacajaweana) - Style the same length of the corolla. Corolla lobes short and spreading only slightly if at all at the tips. Flowers generally longer than 2 cm.
Scouler's Harebell, Scouler's Campanula, Pale Bellflower: Campanula scouleri - Style much longer than the corolla, exserted from the corolla. Corolla lobes long and spreading widely. Flowers up to 1.5 cm long.