Linum lewisii Linum lewisii Linum lewisii ("Linum perenne" var. "lewisii") (Lewis flax, blue flax or prairie flax) is a perennial plant in the family Linaceae, native to western North America from Alaska south to Baja California, and from the Pacific Coast east to the Mississippi River (USDA Plant Profile: "Linum lewisii"). It grows on ridges and dry slopes, from sea level in the north up to in the Sierra Nevada. It is a slender herbaceous plant growing to 80 cm tall, with spirally arranged narrow lanceolate leaves 1–2 cm long. The flowers are pale blue or lavender to white, often veined in
The Different Forms of Flowers on Plants of the Same Species increase the fertility of this common plant. The same thing was found to occur in the primrose, as well as in flax (Linum perenne), lungworts (Pulmonaria), and a host of other plants, including the American partridge-berry (Mitchella repens). These are called dimorphic heterostyled plants. Still more extraordinary is the case of the common loosestrife (Lythrum salicaria), which has both stamens and styles of three distinct lengths, each flower having two sets of stamens and one style, all of different lengths, and arranged in three different ways: These flowers can be fertilised in eighteen distinct ways, necessitating a vast number of