Bluebells are hairless to flat-short-hairy or stiff-hairy perennial herbs, the hairs not with sharp tips. The flowers are arranged in bractless, mostly small clusters ending the stem and branches. The calyx is generally cleft at least to the middle, often to the base, with 5 lobes. The corolla is blue, or in occasional individuals white or pink, shallowly 5-lobed, bell-shaped, generally abruptly expanded at the throat and thus evidently divided into a tube and limb (M. bella excepted). The fornices are usually evident. The filaments are attached at or below the level of the fornices, and are often conspicuously expanded. The fruits consist of nutlets which are attached sideways to the base at or below the middle, and they have a generally wrinkled surface. The genus consists of about 35 or 40 species worldwide, native to extratropical Eurasia and N. America, most of them in w. U.S. It's named for F. C. Mertens, 1764-1831, German botanist.
Guide to Identify Presented Species of Genus Mertensia
PLANTS MOSTLY TALLER THAN 40 CM. MOIST HABITATS
M. ciliata Mountain Bluebells Stems numerous, 15-100 cm tall. Flowers blue, nodding, 10-17 mm long, the limb about as long as the tube. Leaves alternate, elliptic to egg-shaped, with tapered bases. Moist to wet areas, foothills to subalpine.