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An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Hamamelidae of the class Magnoliopsida (dicotyledons). The order consists of the single family Myricaceae, with about 50 species. Within its subclass the order is marked by its simple, resinous-dotted, aromatic leaves and unilocular ovary with two styles and a single ovule. The plants are trees or shrubs, and the flowers are much reduced and borne in catkins. The fruit is a small, waxy-coated drupe or nut. Several species of <i>Myrica</i> are occasionally cultivated as ornamentals.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Hamamelidae of the class Magnoliopsida (dicotyledons). The order consists of two families: the Juglandaceae with a little over 50 species and the Rhoipteleaceae with only one species. Within its subclass the order is sharply set off by its compound leaves. <i>Juglans</i> (walnut and butternut) and <i>Carya</i> (hickory, including the pecan, <i>C. illinoensis</i>) are familiar genera of the Juglandaceae.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Hamamelidae of the class Magnoliopsida (dicotyledons). The order contains a single family with but one genus, <i>Didymeles</i>, with two species. These dioecious, evergreen trees are restricted to Madagascar. The wood has vessels with scalariform perforations, which is a putatively primitive feature. The leaves are alternate, simple, and entire. The flowers are small; the staminate ones are in open clusters, without perianth, with two stamens, and the pollen grains have three germinal furrows. The pistillate flowers are commonly paired in spikelike clusters; they are hypogynous and sometimes have 1–4 scalelike sepals but no petals. The pistil has but one carpel. This curious genus has often been included in the Hamamelidales; however, the primitive nature of the wood and of the pistil make it anomalous there.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Magnoliidae of the class Magnoliopsida (dicotyledons). It contains only the family Aristolochiaceae, with 8 or 10 genera and about 600 species, most of them in tropical and subtropical regions. Within its subclass the order is marked by the presence of ethereal oil cells, by its uniaperturate or nonaperturate pollen, and especially by its strongly perigynous to epigynous flowers, usually with united carpels, that typically lack petals and have the sepals joined into a highly irregular, corolloid calyx. Many of the species are climbing vines. <i>Aristolochia</i> (birthwort or Dutchman's pipe) and <i>Asarum</i> are well-known genera of the order.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Magnoliidae of the class Magnoliopsida (dicotyledons). The order consists of two families, Illiciaceae and Schisandraceae, with fewer than a hundred species in all. They are all woody, with scattered spherical cells containing volatile oils. The leaves are alternate and simple. The flowers are solitary or a few clustered together, regular, and hypogynous; the perianth has five to many segments that are not clearly differentiated into sepals and petals. The Illiciales are related to the Magnoliales and have sometimes been included in that order, but they are apparently more advanced in having fundamentally triaperturate pollen. <i>Illicium</i>, with about 40 species in southeastern Asia and in the Caribbean region, is the source of the spice star anise.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order consists of 10 families and about 2000 species. The largest families are the Loranthaceae (about 900 species), Santalaceae (about 400 species), Viscaceae (about 350 species), and Olacaceae (about 250 species). A few of the more primitive members of the Santalales are autotrophic, but otherwise the order is characterized by progressive adaptation to parasitism, accompanied by progressive simplification of the ovules. In the Loranthaceae the ovules have no integument and are embedded in the large, central placenta. Some other families have a free central placenta with pendulous, terminal ovules; in any case there are only a few ovules, in contrast to the very numerous ovules of the Rafflesiales. Some members of the Santalales, such as sandalwood (<i>Santalum album</i>, a small tree of southern Asia), are rooted in the ground and produce small branch roots which invade and parasitize the roots of other plants. Others, such as mistletoe (<i>Viscum</i> and other genera of the Viscaceae), grow on trees, well above the ground.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order consists of 2 families, with about 150 species in all. The Haloragales are herbs with perfect or often unisexual, more or less reduced flowers. The perianth is minute or vestigial and was probably originally tetramerous. The ovary is inferior, with only one ovule in each locule, and the seeds have a more or less abundant endosperm. Many of the species are aquatic. Entomophily (pollination by insects) has been largely abandoned in the group, and the pollen is commonly distributed by wind or water. The aquarium plant called parrot's feather (<i>Myriophyllum</i>, family Haloragaceae) and the very large-leaved plant <i>Gunnera</i> (family Gunneraceae) are well-known members of the Haloragales.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order consists of the large family Euphorbiaceae (about 7500 species) and 3 small satellite families which have fewer than 100 species among them. The Euphorbiales are a group of few-ovulate, mostly simple-leaved Rosidae in which the flowers have become unisexual and then undergone further reduction accompanied by aggregation. The trend toward reduction and aggregation culminates in the very large genus <i>Euphorbia</i>, with perhaps 1500 species, in which the pseudanthium has a pistillate flower consisting of a naked, tricarpellate pistil surrounded by several staminate flowers, each of which consists of a single stamen. The illusion that this cluster constitutes a single flower is fostered also by the cup-shaped involucre which often bears showy, petallike appendages. The Christmas poinsettia (<i>E. pulcherrima</i>) and the para rubber tree (<i>Hevea brasiliensis</i>) are well-known members of the Euphorbiaceae. Many African euphorbiads are spiny stem-succulents which resemble cacti in habit. Aside from the pronounced floral differences, the euphorbiads have a milky juice, which the cacti do not.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order consists of three closely related families (Mimosaceae, Caesalpiniaceae, Fabaceae) collectively called the legumes. Members of the order typically have stipulate, compound leaves, 10–many stamens which are often united by the filaments, and a single carpel which gives rise to a dry fruit (legume) that opens at maturity by splitting along two sutures, releasing the non-endospermous seeds. Many, or perhaps most, members of the order harbor symbiotic nitrogen-fixing bacteria in the roots.
Industry:Science
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Rosidae of the class Magnoliopsida (dicotyledons). The order consists of three families and fewer than a hundred species, nearly all tropical or subtropical. The plants are highly specialized, nongreen, rootless parasites which grow from the roots of the host. They have few or solitary, rather large to very large flowers with numerous ovules and a single set of tepals that are commonly united into a conspicuous, corolloid calyx. <i>Rafflesia</i> is famous for its gigantic flowers, which in <i>R. arnoldii</i> of Sumatra are about 3 ft (1 m) in diameter. No other family has individual flowers even approaching this size.
Industry:Science
