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Euphorbia (subgenus)
''Euphorbia'' is a very large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae (in deference to the type genus), not just to members of the genus. Euphorbias range from tiny annual plants to large and long-lived trees. The genus has roughly 2,000 members, making it one of the largest genera of flowering plants. It also has one of the largest ranges of chromosome counts, along with ''Rumex'' and ''Senecio''. ''Euphorbia antiquorum'' is the type species for the genus ''Euphorbia''. It was first described by Carl Linnaeus in 1753 in ''Species Plantarum''. Some euphorbias are widely available commercially, such as poinsettias at Christmas. Some are commonly cultivated as ornamentals, or collected and highly valued for the aesthetic appearance of their unique floral structures, such as the crown of thorns plant (''Euphorbia milii''). S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
August Grisebach
August Heinrich Rudolf Grisebach () was a German botany, botanist and phytogeography, phytogeographer. He was born in Hannover on 17 April 1814 and died in Göttingen on 9 May 1879. Biography Grisebach studied at the Lyceum in Hanover, the cloister-school at Ilfeld, and the University of Göttingen. He graduated in medicine from the University of Berlin (other), University of Berlin in 1836. He undertook expeditions to Provence, Turkey, the Balkans, and Norway. In 1837 he became associate professor and in 1847 full professor at the medical faculty in Göttingen and was named director of Old Botanical Garden of Göttingen University, the botanical garden there in 1875. While his main fields of interest were phytogeography and systematics, especially the Gentianaceae and Malpighiaceae, he considered his ''Flora of the British West Indian Islands'' his most important work. Much of his collection, especially the Type (biology), types of species described by him, are housed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Senecio
''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels. Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants. Description Morphology The flower heads are normally rayed with the heads borne in branched clusters, and usually completely yellow, but green, purple, white and blue flowers are known as well. In its current circumscription, the genus contains species that are annual or perennial herbs, shrubs, small trees, aquatics or climbers. The only species which are trees are the species formerly belonging to '' Robinsonia'' occurring on the Juan Fernández Islands. Chemistry Pyrrolizidine alkaloids are found in all ''Senecio'' species. These alkaloids serve as a natural biocides to deter or even kill animals that would eat them. Livestock generally do not find them palatable. ''Senecio'' species are used as food plants by the larvae of some Lepidoptera species t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pistil
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 calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stamen
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 ''sporangium, 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 (plant), Canna'' species or as many as 3,482 stamens which have been counted in the saguaro (''Carnegiea gigantea'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyathium
A cyathium (plural: cyathia) is one of the specialised pseudanthia ("false flowers") forming the inflorescence of plants in the genus ''Euphorbia'' (Euphorbiaceae). A cyathium consists of: * Five (rarely four) bracteoles. These are small, united bracts, which form a cup-like involucre. Their upper tips are free and in the beginning cover the opening of the involucre (like the shutter of a camera). These alternate with: * Five (1 to 10) nectar glands, which are sometimes fused. * One extremely reduced female flower standing in the centre at the base of the involucre, consisting of an ovary on a short stem with pistil, and surrounded by: * Five groups (one group at the base of each bracteole) of extremely reduced male flowers, which each consist of a single anther on a stem. The flower-like characteristics of the cyathia are underlined by brightly coloured nectar glands and often by petal-like appendages to the nectar glands, or brightly coloured, petal-like bracts positioned un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudanthium
A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers, or capitula, which are special types of inflorescences in which anything from a small cluster to hundreds or sometimes thousands of flowers are grouped together to form a single flower-like structure. Pseudanthia take various forms. The real flowers (the florets) are generally small and often greatly reduced, but the pseudanthium itself can sometimes be quite large (as in the heads of some varieties of sunflower). Pseudanthia are characteristic of the daisy and sunflower family (Asteraceae), whose flowers are differentiated into ray flowers and disk flowers, unique to this family. The disk flowers in the center of the pseudanthium are actinomorphic and the corolla is fused into a tube. Flowers on the periphery are zygomorp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latex
Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latexes are found in nature, but synthetic latexes are common as well. In nature, latex is found as a milky fluid found in 10% of all flowering plants (angiosperms). It is a complex emulsion that coagulates on exposure to air, consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins, and gums. It is usually exuded after tissue injury. In most plants, latex is white, but some have yellow, orange, or scarlet latex. Since the 17th century, latex has been used as a term for the fluid substance in plants, deriving from the Latin word for "liquid". It serves mainly as defense against herbivorous insects. Latex is not to be confused with plant sap; it is a distinct substance, separately produced, and with different functions. The word latex is also used to refer to natural latex rubber, particularly non-vulcanized rubber. Such is the case in products like latex gloves, latex condoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cacti
A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek word (''káktos''), a name originally used by Theophrastus for a spiny plant whose identity is now not certain. Cacti occur in a wide range of shapes and sizes. Although some species live in quite humid environments, most cacti live in habitats subject to at least some drought. Many live in extremely dry environments, even being found in the Atacama Desert, one of the driest places on Earth. Because of this, cacti show many adaptations to conserve water. For example, almost all cacti are succulents, meaning they have thickened, fleshy parts adapted to store water. Unlike many other succulents, the stem is the only part of most cacti where this vital process takes place. Most species of cacti have lost true leaves, retaining only spines, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa across the Mozambique Channel. At Madagascar is the world's List of island countries, second-largest island country, after Indonesia. The nation is home to around 30 million inhabitants and consists of the island of Geography of Madagascar, Madagascar (the List of islands by area, fourth-largest island in the world), along with numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian subcontinent around 90 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of wildlife of Madagascar, its wildlife is endemic. Human settlement of Madagascar occurred during or befo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With billion people as of , it accounts for about of the world's human population. Africa's population is the youngest amongst all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Despite a wide range of natural resources, Africa is the least wealthy continent per capita and second-least wealthy by total wealth, behind Oceania. Scholars have attributed this to different factors including geography, climate, tribalism, colonialism, the Cold War, neocolonialism, lack of democracy, and corruption. Despite this low concentration of wealth, recent economic expansion and the large and young population make Afr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Succulent Plant
In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meaning "juice" or "sap". Succulent plants may store water in various structures, such as leaf, leaves and Plant stem, stems. The water content of some succulent organs can get up to 90–95%, such as ''Glottiphyllum semicyllindricum'' and ''Mesembryanthemum barkleyii''. Some definitions also include roots, thus geophytes that survive unfavorable periods by dying back to underground storage organs may be regarded as succulents. The habitats of these water-preserving plants are often in areas with high temperatures and low rainfall, such as deserts, but succulents may be found even in Alpine climate, alpine ecosystems growing in rocky soil. Succulents are characterized by their ability to thrive on limited water sources, such as mist and dew, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euphorbia Milii
''Euphorbia milii'', the crown of thorns, Christ plant, or Christ thorn, is a species of flowering plant in the spurge family Euphorbiaceae, native to Madagascar. The species name commemorates Baron Milius, once Governor of Réunion, who introduced the species to France in 1821. It is imagined that the species was introduced to the Middle East in ancient times, and legend associates it with the crown of thorns worn by Christ. It is commonly used as an ornamental houseplant that can be grown in warmer climates. The common name is due to the thorns and deep red bracts referring to the crown thorn Jesus had to wear during his crucifixion and his blood. Description It is a woody succulent subshrub or shrub growing to tall, with densely spiny stems. The straight, slender spines, up to long, help it scramble over other plants. The fleshy, green leaves are found mainly on new growth, and are up to long and broad. The flowers are small, subtended by a pair of conspicuous petal-li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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