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Strobiloideae
The Strobiloideae are an obsolete taxonomic name, a subclass of both Monocotyledons and Dicotyledons proposed by Charles Bessey in 1915 in his taxonomic classification of plants. In this sense by not being unique it breaks the rules of botanical nomenclature as currently used, however Bessey actually used a qualifying hyphenation (Alternifoliae-Strobiloideae and Oppositifoliae-Strobiloideae), a distinction not always recognised in reference to this scheme. Bessey believed in the strobiloid theory of plant evolution that postulated that the Angiospermae (flowering plants) originated from Cycadophyta, and that flowers originated from a primitive vegetative shoot that developed into a structure with perianth, stamens and carpels. From this arose two lines, the Strobiloideae (or Ranalian line) with connation of like parts and the Cotyloideae (or Rosalian line) with connation of unlike parts, which he assigned as the two subclasses of monocots (called Alternifoliae by Bessey), but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bessey System
A system of plant taxonomy, the Bessey system was published by Charles Bessey in 1915. Description Bessey based his system on the tradition of de Candolle, Bentham and Hooker and Hallier. He was also influenced by Darwin and Wallace. He taught that taxonomy must be based on evolutionary principles. Like Wettstein he placed the Ranales at the origin of Angiospermae. He considered Spermatophyta as having a polyphyletic origin, being composed by three different phyla, of which he only treated Anthophyta (syn.: Angiosperms). In that he used the same names for the subclasses of both monocotyledons and dicotyledons, this is contrary to contemporary rules on plant nomenclature that require names to be unique. However Bessey actually used a qualifying hyphenation (Alternifoliae-Strobiloideae and Oppositifoliae-Strobiloideae), a distinction not always recognised in reference to this scheme. With some modifications, most modern classifications - for example, those of Cronquist (1981 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxon
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were set forth in Carl Linnaeus's Linnaean taxonomy, system in ''Systema Naturae'', 10th edition (1758), as well as an unpublished work by Bernard de Jussieu, Bernard and Antoine Laurent de Jussieu. The idea of a unit-based system of biological classification was first mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamens
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament and an anther which contains ''microsporangia''. Most commonly anthers are two-lobed and are attached to the filament either at the base or in the middle area of the anther. The sterile tissue between the lobes is called the connective, an extension of the filament containing conducting strands. It can be seen as an extension on the dorsal side of the anther. A pollen grain develops from a microspore in the microsporangium and contains the male gametophyte. The stamens in a flower are collectively called the androecium. The androecium can consist of as few as one-half stamen (i.e. a single locule) as in '' Canna'' species or as many as 3,482 stamens which have been counted in the saguaro (''Carnegiea gigantea''). The androecium in vario ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poales
The Poales are a large order of flowering plants in the monocotyledons, and includes families of plants such as the grasses, bromeliads, and sedges. Sixteen plant families are currently recognized by botanists to be part of Poales. Description The flowers are typically small, enclosed by bracts, and arranged in inflorescences (except in three species of the genus ''Mayaca'', which possess very reduced, one-flowered inflorescences). The flowers of many species are wind pollinated; the seeds usually contain starch. Taxonomy The APG III system (2009) accepts the order within a monocot clade called commelinids, and accepts the following 16 families: The earlier APG system (1998) adopted the same placement of the order, although it used the spelling "commelinoids". It did not include the Bromeliaceae and Mayaceae, but had the additional families Prioniaceae (now included in Thurniaceae), Sparganiaceae (now in Typhaceae), and Hydatellaceae (now transferred out of the monocots; ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palmales
The Arecaceae is a family of perennial flowering plants in the monocot order Arecales. Their growth form can be climbers, shrubs, tree-like and stemless plants, all commonly known as palms. Those having a tree-like form are called palm trees. Currently, 181 genera with around 2,600 species are known, most of which are restricted to tropical and subtropical climates. Most palms are distinguished by their large, compound, evergreen leaves, known as fronds, arranged at the top of an unbranched stem. However, palms exhibit an enormous diversity in physical characteristics and inhabit nearly every type of habitat within their range, from rainforests to deserts. Palms are among the best known and most extensively cultivated plant families. They have been important to humans throughout much of history. Many common products and foods are derived from palms. In contemporary times, palms are also widely used in landscaping. In many historical cultures, because of their importance as f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arales
''Arales'' is an order of flowering plants. The name was used in the Cronquist system for an order placed in subclass ''Arecidae'', circumscribed as (1981): * order ''Arales'' *: family ''Acoraceae'' *: family ''Araceae'' *: family ''Lemnaceae'' In the classification system of Dahlgren the Arales were in the superorder Ariflorae (also called Aranae), but did not include Acoraceae as a separate family. Instead, ''Acorus'', its only genus, was included in the Araceae. Arales was the only order included in the Ariflorae. The APG II system elevates the first of these three families to become an order ''Acorales'' of its own (consisting of the single genus, ''Acorus'') and unites the last two of these families into the one family ''Araceae'' assigning this to the order ''Alismatales The Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly Tropical vegetation, tropical or Aquatic plant, aquatic. Some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liliales
Liliales is an order of monocotyledonous flowering plants in the Angiosperm Phylogeny Group and Angiosperm Phylogeny Web system, within the lilioid monocots. This order of necessity includes the family Liliaceae. The APG III system (2009) places this order in the monocot clade. In APG III, the family Luzuriagaceae is combined with the family Alstroemeriaceae and the family Petermanniaceae is recognized. Both the order Lililiales and the family Liliaceae have had a widely disputed history, with the circumscription varying greatly from one taxonomist to another. Previous members of this order, which at one stage included most monocots with conspicuous tepals and lacking starch in the endosperm are now distributed over three orders, Liliales, Dioscoreales and Asparagales, using predominantly molecular phylogenetics. The newly delimited Liliales is monophyletic, with ten families. Well known plants from the order include ''Lilium'' (lily), tulip, the North American wildflower ''Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alismatales
The Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly tropical or aquatic. Some grow in fresh water, some in marine habitats. Description The Alismatales comprise herbaceous flowering plants of often aquatic and marshy habitats, and the only monocots known to have green embryos other than the Amaryllidaceae. They also include the only marine angiosperms growing completely submerged, the seagrasses. The flowers are usually arranged in inflorescences, and the mature seeds lack endosperm. Both marine and freshwater forms include those with staminate flowers that detach from the parent plant and float to the surface. There they can pollinate carpellate flowers floating on the surface via long pedicels. In others, pollination occurs underwater, where pollen may form elongated strands, increasing chance of success. Most aquatic species have a totally submerged juvenile phase, and flowers are either ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connation
Connation in plants is the developmental fusion of organs of the same type, for example, petals to one another to form a tubular corolla. This is in contrast to adnation, the fusion of dissimilar organs. Such organs are described as connate or adnate, respectively. When like organs that are usually well separated are placed next to each other, but not actually connected, they are described as connivent (that is the case for anthers in several genera, such as ''Solanum''). Terms for connation of flower parts *Synsepalous: All the sepals of a flower are fused into a cup or tube; the fused portion is the calyx tube, and any non fused tips are the calyx lobes. *Sympetalous: All the petals of a flower are fused into a cup, tube, or other shape. *Stamens: **Synandrous: Stamens are fused in an unspecified manner **Synfilamentous: Stamens are fused by their filaments **Synantherous: Stamens are fused by their anthers *Syncarpous: Carpels are fused together to form a compound ovary Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpels
Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' and is typically surrounded by the pollen-producing reproductive organs, the stamens, collectively called the androecium. The gynoecium is often referred to as the "female" portion of the flower, although rather than directly producing female gametes (i.e. egg cells), the gynoecium produces megaspores, each of which develops into a female gametophyte which then produces egg cells. The term gynoecium is also used by botanists to refer to a cluster of archegonia and any associated modified leaves or stems present on a gametophyte shoot in mosses, liverworts, and hornworts. The corresponding terms for the male parts of those plants are clusters of antheridia within the androecium. Flowers that bear a gynoecium but no stamens are called ''pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perianth
The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower, and structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepals when called a perigone. The term ''perianth'' is derived from Greek περί (, "around") and άνθος (, "flower"), while ''perigonium'' is derived from περί () and γόνος (, "seed, sex organs"). In the mosses and liverworts (Marchantiophyta), the perianth is the sterile tubelike tissue that surrounds the female reproductive structure (or developing sporophyte). Flowering plants In flowering plants, the perianth may be described as being either dichlamydeous/heterochlamydeous in which the calyx and corolla are clearly separate, or homochlamydeous, in which they are indistinguishable (and the sepals and petals are collectively referred to as tepals). When the perianth is in two whorls, it is described as biseriate. While the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
