Convolvulus

Convolvulus, a genus comprising about 100 species, forming the type of the order Convolvulaceae. They are slender twining or trailing plants with a milky juice, and often containing a purgative resin. They have scattered, exstipulate leaves; no bracts below the calyx; a conspicuous funnel, belt, or trumpet-shaped corolla of five united petals; five stamens and a two-chambered ovary containing four seeds. With the pink and white-flowered Convolvulus arvensis, a pretty cornfield weed, are commonly united the forms with two large bracts below the calyx, sometimes known as Calystegia, including the large white C. sepium and the pink sea-side C. Soldanella, both British. C. tricolor, a native of the Mediterranean region, with blue flowers with a white and yellow centre, is commonly known in gardens as "Minor Convolvulus." The root of C. Scammonia yields the purgative drug scammony.