Common Name: EVENING-PRIMROSE FAMILY
Habit: Annual to perennial herb (to tree). Leaf: cauline or basal, alternate, opposite, or whorled, generally simple and toothed (to pinnately compound); stipules 0 or generally deciduous. Inflorescence: spike, raceme, panicle, or flowers 1 in axils; bracted. Flower: generally bisexual, generally radial, often opening at either dawn or dusk; hypanthium generally prolonged beyond ovary (measured from ovary tip to sepal base); sepals 4(2--7); petals 4(2--7, rarely 0), often fading darker; stamens 2 × or = sepals in number, anthers 2-chambered, opening lengthwise, pollen interconnected by threads; ovary inferior, chambers generally as many as sepals (sometimes becoming 1), placentas axile or parietal, ovules 1--many per chamber, style 1, stigma 4-lobed (or lobes as many as sepals), club-shaped, spheric, or hemispheric. Fruit: capsule, loculicidal (sometimes berry or indehiscent and nut-like). Seed: sometimes winged or hair-tufted.
Genera In Family: 22 genera, +- 657 species: worldwide, especially western North America; many cultivated (Clarkia, Epilobium, Fuchsia, Oenothera). Note: Gaura moved to Oenothera. Fuchsia magellanica Lam. naturalized in northern California.
eFlora Treatment Author: Warren L. Wagner & Peter C. Hoch, family description, key to genera, treatment of genera by Warren L. Wagner, except as noted
Scientific Editor: Robert Patterson, Bruce G. Baldwin.

Habit: Annual. Stem: generally erect, < 1 m, slender; hairs 0 to dense, rarely glandular. Leaf: cauline, alternate (or +- opposite near base), petioled or not, narrow-lanceolate, entire. Inflorescence: flowers axillary, pedicelled or not, opening at dawn. Flower: hypanthium inconspicuous; sepals 4, staying fused in 2s or all coming free; petals 4, 0.5--8 mm, white, with 1--2 yellow or +- green spots at base, fading pink or red; stamens 8, those opposite sepals longer, pollen +- yellow; ovary chambers 2, stigma generally not exserted beyond anthers, generally touching them, generally +- spheric. Fruit: capsule, +- cylindric or flat; valves 4, generally all coming free, generally equal. Seed: few to many, generally all maturing, generally appressed to septum, alternate or +- opposite between chambers, in each chamber generally in 1 row and generally not overlapped, 0.5--2.3 mm, ovoid, glabrous or hairy, brown or gray mottled with brown; appendages 0.
Species In Genus: +- 9 species: western North America, 2 South America. Etymology: (C. Gay, French author of Flora of Chile, 1800--1873) Note: Self-fertile; taxa with petals < 3 mm self-pollinated.
eFlora Treatment Author: Harlan Lewis
Unabridged Reference: Lewis & Szweykowski 1964 Brittonia 16:343--391