harebell, (Campanula rotundifolia), widespread, slender-stemmed perennial of the family Campanulaceae. The harebell bears nodding blue bell-like flowers. It is native to woods, meadows, and cliffsides of northern Eurasia and North America and of mountains farther south. There are more than 30 named wild varieties of Campanula rotundifolia. Small, round, basal leaves disappear before the flowers form, leaving only long, slender stem leaves. The delicate stems of harebells grow in clumps and reach a height of 30 to 60 centimetres (1 to 2 feet). Each stem bears one to several drooping blue-violet bells.