Monographs Details: Jacquemontia pentantha (Jacq.) G.Don
Authority: Britton, Nathaniel L. Flora Borinqueña.
Description:Species Description - Blooming abundantly, and often covering banks with its beautiful blue flowers, this slender, herbaceous vine is frequent in dry and moist districts, at lower and middle elevations in Porto Rico, ascending to about 400 meters, and grows also on Mona, Cayo Muertos, Vieques and Culebra; the shade of blue in flowers of different vines, or of different colonies is various, some being much paler than others; a race with pure white flowers occurs, but rarely; we had the pleasure of seeing this some years ago, along the road from Aquadilla to Cape Borinquen. The vine inhabits thickets, banks and hillsides, and is either prostrate, or twines on bushes; it is distributed naturally from Florida and the Bahama Islands, throughout the West Indies, south to Barbados, and on the continent from northern Mexico to Panama and Brazil.
Jacquemontia, a genus established by the Swiss botanist Choisy, a diligent student of plants of this family, in 1833, commemorates Victor Jacquemont, a French botanical traveller, who died in 1828, and consists of 30 species, or more, natives of tropical and subtropical America. They are vines, mostly herbaceous, with broad or narrow leaves, and clustered, violet, blue, or white flowers. The 5 sepals are alike, or the outer ones larger than the inner; the corolla is mostly broadly bell-shaped with a 5-angled limb; the 5 stamens are shorter than the corolla, their filaments slender; the 2-celled ovary usually contains 4 ovules; the 2 styles are united, the 2 stigmas flat. The fruit is a 2-celled, few-seeded capsule.
Jacquemontia pentantha (five-flowered) is hairy, or nearly smooth, 2 meters long, or shorter, sometimes much branched. The ovate, slender-stalked, pointed leaves are from 2 to 4 centimeters long, the base heart-shaped. The flowers are few together in long-stalked clusters; the pointed sepals are from 5 to 7 millimeters long, the outer ones broader than the inner; the corolla is from 2 to 3 centimeters broad, blue, or blue with white plaits, rarely white. The nearly globular capsule is about as long as the sepals.
Two other species of Jacquemontia are illustrated in this work.
Small Blue Morning-glory
Convolvulus pentanthos Jacquin, Collecteana 4: 210. 1790.
Jacquemontia pentantha George Don, General History of Plants 4: 283.1838.