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Floral Formula
A floral formula is a notation for representing the structure of particular types of flowers. Such notations use numbers, letters and various symbols to convey significant information in a compact form. They may represent the floral form of a particular species, or may be generalized to characterize higher taxon, taxa, usually giving ranges of numbers of organs. Floral formulae are one of the two ways of describing flower structure developed during the 19th century, the other being floral diagrams. The format of floral formulae differs according to the tastes of particular authors and periods, yet they tend to convey the same information. A floral formula is often used along with a floral diagram. History Floral formulae were developed at the beginning of the 19th century. The first authors using them were Cassel (1820), who first devised lists of integers to denote numbers of parts in named whorls, and Martius (1828). Grisebach (1854) used 4-integer series to represent the 4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floral Diagram
A floral diagram is a graphic representation of the structure of a flower. It shows the number of floral organs, their arrangement and fusion. Different parts of the flower are represented by their respective symbols. Floral diagrams are useful for flower identification or can help in understanding angiosperm evolution. They were introduced in the late 19th century and are generally attributed to A. W. Eichler. They are typically used with the floral formula of that flower to study its Morphology (biology), morphology. History In the 19th century, two contrasting methods of describing the flower were introduced: the textual floral formulae and pictorial floral diagrams. Floral diagrams are credited to A. W. Eichler, whose extensive work ''Blüthendiagramme'' (1875, 1878) remains a valuable source of information on floral morphology. Eichler inspired later generations of scientists, including John Henry Schaffner. Diagrams were included e.g. in ''Types of Floral Mechanism'' by Art ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anagallis Arvensis 2
''Anagallis'' is a formerly recognized genus of flowering plants in the family (biology), family Primulaceae. It had about 20–25 species, commonly called pimpernels. Molecular phylogenetics, Molecular phylogenetic studies showed that ''Anagallis'' was embedded in the genus ''Lysimachia'', so its species were transferred to that genus. The Lysimachia arvensis, scarlet pimpernel referred to in literature was part of this genus. Taxonomy The genus name ''Anagallis'' is from the Greek ( 'again') and ( 'to delight in'), and it refers to the opening and closing of the flowers in response to environmental conditions. Molecular phylogenetics, Molecular phylogenetic studies have shown that as then Circumscription (taxonomy), circumscribed neither ''Anagallis'' nor the related genus ''Lysimachia'' were Monophyly, monophyletic. Accordingly in 2009, it was proposed to merge ''Anagallis'' (together with two other small genera) into ''Lysimachia''. Names in that genus were published for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamen
The stamen (: stamina or stamens) is a part consisting of the male reproductive organs 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 sporangium, microsporangia. Most commonly, anthers are two-lobed (each lobe is termed a locule) and are attached to the filament either at the base or in the middle area of the anther. The sterile (i.e. nonreproductive) tissue between the lobes is called the Connective (botany), 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 size of anthers differs greatly, from a tiny fraction of a millimeter in ''Wolfia'' spp up to five inches (13 centimeters) in ''Canna iridiflora'' and ''Strelitzia nicolai''. The stamens in a flower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiral – Floral Formulae
In mathematics, a spiral is a curve which emanates from a point, moving further away as it revolves around the point. It is a subtype of whorled patterns, a broad group that also includes concentric objects. Two-dimensional A two-dimensional, or plane, spiral may be easily described using polar coordinates, where the radius r is a monotonic continuous function of angle \varphi: * r=r(\varphi)\; . The circle would be regarded as a degenerate case (the function not being strictly monotonic, but rather constant). In ''x-y-coordinates'' the curve has the parametric representation: * x=r(\varphi)\cos\varphi \ ,\qquad y=r(\varphi)\sin\varphi\; . Examples Some of the most important sorts of two-dimensional spirals include: * The Archimedean spiral: r=a \varphi * The hyperbolic spiral: r = a/ \varphi * Fermat's spiral: r= a\varphi^ * The lituus: r = a\varphi^ * The logarithmic spiral: r=ae^ * The Cornu spiral or ''clothoid'' * The Fibonacci spiral and golden spiral * The Spi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floral Symmetry
Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirally arranged. Actinomorphic Most flowers are actinomorphic ("star shaped", "radial"), meaning they can be divided into three or more identical sectors which are related to each other by rotation about the center of the flower. Typically, each sector might contain one tepal or one petal and one sepal and so on. It may or may not be possible to divide the flower into symmetrical halves by the same number of longitudinal planes passing through the axis: oleander is an example of a flower without such mirror planes. Actinomorphic flowers are also called radially symmetrical or regular flowers. Other examples of actinomorphic flowers are the lily (''Lilium'', Liliaceae) and the buttercup ('' Ranunculus'', Ranunculaceae). Zygomorphic Zy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pistillode
Gynoecium (; ; : gynoecia) 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staminode
In botany, a staminode is an often rudimentary, sterile or abortive stamen, which means that it does not produce pollen.Jackson, Benjamin, Daydon; ''A Glossary of Botanic Terms with their Derivation and Accent''; Published by Gerald Duckworth & Co. London, 4th ed 1928 Staminodes are frequently inconspicuous and stamen-like, usually occurring at the inner whorl of the flower, but are also sometimes long enough to protrude from the corolla. Sometimes, the staminodes are modified to produce nectar, as in the witch-hazel ''(Hamamelis)''.jin lu mei shu. Hamamelis Linnaeus, Sp. Pl. 1: 124. 1753. Flora of China 9: 32. 2003 Staminodes can be a critical characteristic for differentiating between species, for instance in the orchid genus ''Paphiopedilum'', and among the penstemons. In the case of cannas, the petals are inconsequential and the staminodes are refined into eye-catching petal-like replacements. A spectacular example of staminode is given by ''Couroupita guianensis ''C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degree Symbol
The degree symbol or degree sign, , is a glyph or symbol that is used, among other things, to represent degrees of arc (e.g. in geographic coordinate systems), hours (in the medical field), degrees of temperature or alcohol proof. The symbol consists of a small superscript circle. History The word degree is equivalent to Latin gradus which, since the medieval period, could refer to any stage in a graded system of ranks or steps. The number of the rank in question was indicated by ordinal numbers, in abbreviation with the ordinal indicator (a superscript letter ). Use of "degree" specifically for the degrees of arc, used in conjunction with Arabic numerals, became common in the 16th century, but this was initially without the use of an ordinal marker or degree symbol: instead, various abbreviation of ''gradus'' (e.g., Gra., Gr., gr., G.). The modern notation appears in print in the 1570s, with a borderline example by Jacques Pelletier du Mans in 1569, and was populari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curly Brackets
A bracket is either of two tall fore- or back-facing punctuation marks commonly used to isolate a segment of text or data from its surroundings. They come in four main pairs of shapes, as given in the box to the right, which also gives their names, that vary between British and American English. "Brackets", without further qualification, are in British English the ... marks and in American English the ... marks. Other symbols are repurposed as brackets in specialist contexts, such as those used by linguists. Brackets are typically deployed in symmetric pairs, and an individual bracket may be identified as a "left" or "right" bracket or, alternatively, an "opening bracket" or "closing bracket", respectively, depending on the directionality of the context. In casual writing and in technical fields such as computing or linguistic analysis of grammar, brackets nest, with segments of bracketed material containing embedded within them other further bracketed sub-segments. The num ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tie (typography)
The tie is a symbol in the shape of an arc similar to a large breve, used in Greek, phonetic alphabets, and Z notation. It can be used between two characters with spacing as punctuation, non-spacing as a diacritic, or (underneath) as a proofreading mark. It can be above or below, and reversed. Its forms are called tie, double breve, enotikon or papyrological hyphen, ligature tie, and undertie. Uses Cyrillic transliteration In the ALA-LC romanization for Russian, a tie symbol is placed over some combinations of Latin letters that are represented by a single letter in the Cyrillic alphabet, e.g., T͡S for Ц and i͡a for Я. This is not uniformly applied, however; some letters corresponding to common digraphs in English, such as SH for Ш and KH for Х do not employ the tie. In practice, the tie ligature is often omitted. Greek The enotikon (, ''henōtikón'', "uniter", from "a serving to unite or unify"), papyrological hyphen, or Greek hyphen was a low tie mark ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
