Many of the 272 US species, in 27 genera, of the campanulaceae (bellflower) family are relatively uncommon, and/or are found more towards the east of the country. Flowers are quite large, and tubular in shape - bell-shaped or narrower and more elongated; they can be radially symmetric, opening to five equal lobes, or bilaterally symmetric, with a two-lobed upper lip and a three-lobed lower lip. The flower center contains five stamens. Flowers are colored white, purple or blue. Leaves may be simple or divided, and are usually alternate. The two most widespread genera are campanula and lobelia.