A perennial plant ( Campanula rotundifolia ) having slender stems , dense clusters of basal leaves , and bell - shaped blue or white flowers .
钓钟柳一种长年生的茎细有成簇状且浓密的叶子和蓝色或白色钟状花的植物（圆叶风铃草风铃草属）
Campanula rotundifoliaCampanula rotundifoliaCampanula rotundifolia