Flowers of the liliaceae (lily) family are typically large, multicolored and showy, with three or six fold radial symmetry. The calyx at the base of the flowerhead extends to three sepals, often similar in size and color to the three petals. At the center are a ring of six stamens and an ovary, topped by a three-lobed stigma. A small number of species have two sepals and two petals. Flowers are usually borne singly at the top of the stems, but can also be part of spherical or elongated clusters. Leaves are predominantly basal, and tend to be long, narrow and undivided. Most species sprout from bulbs or swollen roots. Stem leaves are alternately arranged. The US has 159 species in 14 genera, the four largest being calochortus, erythronium, fritillaria and lilium.