morning glory, common name for members of the Convolvulaceae, a family of herbs, shrubs, and small trees (many of them climbing forms) inhabiting warm regions, especially the tropics of America and Asia. The family is characterized by milky sap. The largest groups are the predominantly tropical morning-glory genus ( Ipomoea ), with species most abundant in Mexico, and the bindweed genus ( Convolvulus ) of more temperate regions. Many bindweeds are also called morning glory. Species of both are chiefly herbaceous vines of prolific growth and with colorful funnel-shaped blossoms that often open only in the morning. I. purpurea is the morning glory cultivated as an ornamental in North America. The moonflowers (including I. alba ), tropical American night-blooming vines, have similarly shaped but much larger blossoms, often heavily fragrant. Convolvulus scammonia is the scammony of Asia Minor; a resin exuded from its roots are exported from Aleppo and Smyrna as a medicine. The most important commercial plant of the family, the sweet potato, belongs to the morning-glory genus. The wild sweet potato or potato vine ( I. pandurata ), a common weed of North America, is not eaten. The dodders (genus Cuscuta, usually classified as a separate family) are common leafless, parasitic vines that often resemble bright orange threads. Each of the widely distributed species parasitizes a specific host; C. epilinum, for example, lives on flax. The morning-glory family is classified in the division Magnoliophyta, class Magnoliopsida, order Polemoniales.