|
Asplenium × Boydstoniae
''Asplenium'' × ''boydstoniae'', commonly known as Boydston's spleenwort, is a rare, sterile, hybrid fern. It is formed by the crossing of Tutwiler's spleenwort ( ''A. tutwilerae'') with ebony spleenwort ( ''A. platyneuron''). The hybrid was produced in culture in 1954. It was not discovered in the wild until 1971, when it was found by Kerry S. Walter at Havana Glen, Alabama, the only known wild site for Tutwiler's spleenwort. Walter named it for Kathryn E. Boydston, an expert in fern culture. Except for the tip of its leaf blade, it largely resembles its ebony spleenwort parent. Description ''Asplenium'' × ''boydstoniae'' is a small fern, similar to ebony spleenwort. The stem is a shiny dark brown, its color extending almost to the tip of the leaf blade, where it becomes green. Most of the blade is cut into pinnae, but it has an elongated, lobed tip. The fronds of ''A.'' × ''boydstoniae'' can be up to or long and or wide. The stipe (the st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridisation, which include genetic and morphological differences, differing times of fertility, mating behaviors and cues, and physiological rejection of sperm cells or the developing embryo. Some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium × Kentuckiense
''Asplenium'' × ''kentuckiense'', commonly known as Kentucky spleenwort, is a rare, sterile, hybrid fern. It is formed by the crossing of lobed spleenwort ( ''A. pinnatifidum'') with ebony spleenwort ( ''A. platyneuron''). Found intermittently where the parent species grow together in the eastern United States, it typically grows on sandstone cliffs, but is known from other substrates as well. Description ''Asplenium'' × ''kentuckiense'' is a small fern, whose fronds grow in upright, spreading tufts. The stem is a shiny dark brown, the color extending well into the leaf blade. The blades are cut into pinnae near the base, which diminish into lobes in the upper part and eventually to teeth on the sides of a long, drawn-out tip. The fronds are dimorphic, with the fertile fronds much longer and of a different shape than the sterile fronds. The fronds of ''A.'' × ''kentuckiense'', which are long, are closely spaced along a rhizome in diameter. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pottsville Formation
The Pennsylvanian Pottsville Formation is a mapped bedrock unit in Pennsylvania, western Maryland, West Virginia, Ohio, and Alabama. It is a major ridge-former in the Ridge-and-Valley Appalachians of the eastern United States. The Pottsville Formation is conspicuous at many sites along the Allegheny Front, the eastern escarpment of the Allegheny or Appalachian Plateau. Description The Pottsville Formation consists of a gray conglomerate, fine to coarse grained sandstone, and is known to contain limestone, siltstone and shale, as well as anthracite and bituminous coal. It is considered a classic orogenic molasse. The formation was first described from a railroad cut south of Pottsville, Pennsylvania. Nomenclature and Stratigraphy The relationship to the term "Pottsville" and actual lithologic units is complex. Most fundamentally, the unit may be considered a Formation or a Group. As a Formation, the Pottsville may encompass the following members depending on the state in w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions. Rock formations that are primarily composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siliceous
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and most abundant families of materials, existing as a compound of several minerals and as a synthetic product. Notable examples include fused quartz, fumed silica, silica gel, opal and aerogels. It is used in structural materials, microelectronics (as an electrical insulator), and as components in the food and pharmaceutical industries. Structure In the majority of silicates, the silicon atom shows tetrahedral coordination, with four oxygen atoms surrounding a central Si atomsee 3-D Unit Cell. Thus, SiO2 forms 3-dimensional network solids in which each silicon atom is covalently bonded in a tetrahedral manner to 4 oxygen atoms. In contrast, CO2 is a linear molecule. The starkly different structures of the dioxide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conglomerate (geology)
Conglomerate () is a clastic sedimentary rock that is composed of a substantial fraction of rounded to subangular gravel-size clasts. A conglomerate typically contains a matrix of finer-grained sediments, such as sand, silt, or clay, which fills the interstices between the clasts. The clasts and matrix are typically cemented by calcium carbonate, iron oxide, silica, or hardened clay. Conglomerates form by the consolidation and lithification of gravel. They can be found in sedimentary rock sequences of all ages but probably make up less than 1 percent by weight of all sedimentary rocks. In terms of origin and depositional mechanisms, they are closely related to sandstones and exhibit many of the same types of sedimentary structures, e.g., tabular and trough cross-bedding and graded bedding.Boggs, S. (2006) ''Principles of Sedimentology and Stratigraphy.'', 2nd ed. Prentice Hall, New York. 662 pp. Friedman, G.M. (2003) ''Classification of sediments and sedimentary rocks.'' In G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichen
A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not s. They may have tiny, leafless branches (); flat leaf-like structures ( |
Moss
Mosses are small, non-vascular flowerless plants in the taxonomic division Bryophyta (, ) '' sensu stricto''. Bryophyta (''sensu lato'', Schimp. 1879) may also refer to the parent group bryophytes, which comprise liverworts, mosses, and hornworts. Mosses typically form dense green clumps or mats, often in damp or shady locations. The individual plants are usually composed of simple leaves that are generally only one cell thick, attached to a stem that may be branched or unbranched and has only a limited role in conducting water and nutrients. Although some species have conducting tissues, these are generally poorly developed and structurally different from similar tissue found in vascular plants. Mosses do not have seeds and after fertilisation develop sporophytes with unbranched stalks topped with single capsules containing spores. They are typically tall, though some species are much larger. ''Dawsonia'', the tallest moss in the world, can grow to in height. There are a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asplenium Rhizophyllum
''Asplenium rhizophyllum'', the (American) walking fern, is a frequently-occurring fern native to North America. It is a close relative of '' Asplenium ruprechtii'' (syn: ''Camptosorus sibiricus'') which is found in East Asia and also goes by the common name of "walking fern". Description ''Asplenium rhizophyllum'' is a small fern whose undivided, evergreen leaves and long, narrow leaf tips, sometimes curving back and rooting, give it a highly distinctive appearance. It grows in tufts, often surrounded by child plants formed from the leaf tips. The leaves of younger plants tend to lie flat to the ground, while older plants have leaves more erect or arching. Roots and rhizomes It does not spread and form new plants via the roots. Its rhizomes (underground stems) are upright or nearly so, short, about in diameter, and generally unbranched. They bear dark brown or blackish, narrowly triangular or lance-shaped scales which are strongly clathrate (bearing a lattice-like pattern). The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spleenwort
''Asplenium'' is a genus of about 700 species of ferns, often treated as the only genus in the family (biology), family Aspleniaceae, though other authors consider ''Hymenasplenium'' separate, based on molecular phylogenetic analysis of DNA sequences, a different chromosome count, and structural differences in the rhizomes. The type species for the genus is ''Asplenium marinum''. The most common vernacular name is spleenworts, applied to the more "typical" species. ''Asplenium nidus, A. nidus'' and several similar species are called bird's-nest ferns, the ''Camptosorus'' group is known as walking ferns, and distinct names are applied to some other particularly well-known species. Taxonomy and genetics Many groups of species have been separated from ''Asplenium'' as Segregate (taxonomy), segregate genera. These include ''Camptosorus'', ''Ceterach'', ''Phyllitis'', and ''Tarachia'', but these species can form hybrid (biology), hybrids with other ''Asplenium'' species and because of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Description
A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have been described previously or are related. In order for species to be validly described, they need to follow guidelines established over time. Zoological naming requires adherence to the ICZN code, plants, the ICN, viruses ICTV, and so on. The species description often contains photographs or other illustrations of type material along with a note on where they are deposited. The publication in which the species is described gives the new species a formal scientific name. Some 1.9 million species have been identified and described, out of some 8.7 million that may actually exist. Millions more have become extinct throughout the existence of life on Earth. Naming process A name of a new species becomes valid (available in zo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hale County, Alabama
Hale County is a county located in the west central portion of the U.S. state of Alabama. As of the 2020 census, the population was 14,785. Its county seat is Greensboro. It is named in honor of Confederate officer Stephen Fowler Hale. Hale County is part of the Tuscaloosa, AL Metropolitan Statistical Area. History Hale County was established following the end of the American Civil War, on January 30, 1867. Located in the west-central section of the state, it was created from portions of Greene, Marengo, Perry, and Tuscaloosa counties. The vast majority of the territory came from Greene County. The first American settlers in this area had been southerners migrating from Georgia, Tennessee, Kentucky, and the Carolinas. Hale County is connected to three major twentieth-century artists: Walker Evans photographed the area in 1936 while he collaborated with James Agee on the 1941 book ''Let Us Now Praise Famous Men''. Since the 1960s, artist William Christenberry, born in Tus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saunders_Quarry-1.jpg "Click for more on -> Sandstone")
