GENTIANACEAE

Exacum petiolare

Exacum

Canscora diffusa


Swertia

FAMILY OF THE WEEK : GENTIANACEAE

About 80 genera and 700 species worldwide.

Vegetative Characters : Herbs [shrubs or small trees], annual, biennial, or perennial. Stems ascending, erect, or twining. Leaves opposite, less often alternate or whorled, simple, base connate; stipules absent. Inflorescences simple or complex cymes, sometimes reduced to sessile clusters, often in a thyrse or 1-flowered. Flowers bisexual, rarely unisexual, 4 or 5 (or 6-8)[-12]-merous. Calyx tubular, obconic, campanulate, or rotate, lobes joined at least basally. Corolla tubular, obconic, salverform, funnelform, campanulate, or rotate, rarely with basal spurs; lobes overlapping to right or rarely valvate in bud; plicae (extensions of the corolla tube between the lobes) present or absent. Stamens inserted on corolla tube or occasionally at sinus between corolla lobes, alternate with lobes; anthers basifixed or dorsifixed, 2-locular. Nectaries absent or attached to ovary base or corolla. Ovary usually 1-locular at least apically, rarely 2-locular due to intrusion of a lamellate placenta into locular cavity. Fruit a 2-valved capsule, rarely a berry. Seeds many or rarely few, small; endosperm abundant [scant in saprophytic genera].

Pollination by insects.

Examples:

Exacum

Swertia

Enicostema

Centaurium

Hoppea

Canscora