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ONAGRACEAE , in See also:botany, an See also:order of See also:dicotyledons belonging to the See also:series Myrtiflorae, to which belongs also the See also:myrtle order, Myrtaceae. It contains about 36 genera and 300 See also:species, and occurs chiefly in the temperate. See also:zone of the New See also:World, especially on the Pacific See also:side. It is represented in See also:Britain by several species of Epilobium (See also:willow-See also:herb), Circaea (enchanter's See also:nightshade), and Ludwigia, a small perennial herb very rare in boggy pools in See also:Sussex and See also:Hampshire. The See also:plants are generally herbaceous, sometimes See also:annual, as species of Epilobium, Clarkia, Godetia, or biennial, as Oenothera biennis—evening See also:primrose—or sometimes become shrubby or arborescent, as See also:Fuchsia (q.v.). The See also:simple leaves are generally entire or inconspicuously toothed, and are alternate, opposite or whorled in arrangement; they are generally exstipulate, but small See also:caducous stipules occur in Fuchsia, Circaea and other genera. The See also:flowers are often solitary in the See also:leaf-axils, as in many fuchsias, Clarkia, &c., or associated, as in Epilobium and Oenothera, in large showy terminal spikes or racemes; in Circaea the small See also: In Clarkia the inner whorl of stamens is often barren, and in an allied genus, Eucharidium, it is absent. In Circaea the See also:flower has its parts 0 r, Flower cut open after removal of of Circaea. sepals; 2, See also:fruit; 3, floral See also:diagram. in twos. Both sepals and petals are See also:free; the former have a broad insertion, are valvate in bud, and reflexed in the flower; in Fuchsia they are petaloid. The petals have a narrow See also:attachment, and are generally convolute in bud; they are entire (Fuchsia) or bilobed (Epilobium); in some species of Fuchsia they are small and See also:scale-like, or absent (F. apetala). The stamens are free, and those of the inner whorl are generally shorter than those of the See also:outer whorl. The flowers of Lopezia (Central See also:America) have only one fertile stamen. The large spherical See also:pollen grains are connected by viscid threads. The typically quadrilocular ovary contains numerous ovules on See also:axile placentas; the 1-to-2-celled ovary of Circaea has a single sa. ovule in each loculus. The See also:long slender See also:style has a capitate (Fuchsia), 4-rayed (Oenothera, Epilobium) or 4-notched (Cir- caea) stigma. The flowers, which have generally an at- tractive corolla and See also:honey secreted by a swollen disk at the See also:base of the style or on the See also:lower See also:part of the " calyx-tube," are adapted for See also:pollination by See also:insects, chiefly bees and lepi- doptera; sometimes by See also:night- flying insects when the flowers are See also:pale and open towards evening, as in evening primrose. The fruit is generally a See also:capsule splitting into 4 valves and leaving a central See also:column on which the seeds are borne as in Epilobium and Oenothera- in the former the seeds are scattered by aid of a long tuft of silky hairs on the broader end. In Fuchsia the fruit is a See also:berry, which is sometimes edible, and in Circaea a See also:nut bearing recurved bristles. The seeds are exalbuminous. Several of the genera are well known as See also:garden plants, e.g. Fuchsia, Oenothera, Clarkia and Godetia. Evening primrose (Oenothera biennis), a native of See also:North America, occurs apparently See also:wild as a garden See also:escape in Britain. Jussieua is a tropical genus of See also:water- and See also:marsh-herbs with well-See also:developed aerating See also:tissue. Additional information and CommentsThere are no comments yet for this article.
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