|
Egregia Menziesii
''Egregia menziesii'' is a species of kelp known commonly as feather boa kelp. It is the only species in the monotypic genus ''Egregia''. It is native to the coastline of western North America from Alaska to Baja California, where it is a common kelp of the intertidal zone. Description It is dark brown in color, shiny and bumpy in texture, and may reach over five meters long. It grows a branching stipe from a thick holdfast. It bears long, flat, straplike fronds lined with small blades each a few centimeters long. There are pneumatocysts at intervals along the fronds which provide buoyancy. The alga varies in morphology; the rachis, or central strip, of the frond may be smooth or corrugated, and the blades along the edge of the rachis may be a variety of shapes. File:Mysterious kelp.jpg, Feather Boa File:Seaweed & tidepool, North Moonstone SLO.jpg, Feather Boa growing in tidepool File:Alger, Egregia Menziesii, Nordisk familjebok.png, illustration of ''Egregia menziesii'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johan Erhard Areschoug
Johan Erhard Areschoug (Johannes Erhard Areschoug, Philos. Doctor, Botanices et Oeconomiae) (16 September 1811 – 7 May 1887) was a Swedish botanist who was a native of Göteborg. He was a member of the Arreskow family (in Swedish). His first name is sometimes recorded as "John". He studied natural sciences at the University of Lund, where in 1838 he earned his doctorate in philosophy. In 1859 he succeeded Elias Magnus Fries (1794-1878) as professor of botany at the University of Uppsala, a position he maintained until 1876. In 1851, he was elected a member of the Royal Swedish Academy of Sciences. Areschoug performed extensive field studies of Scandinavian cryptogams, being remembered for his work in the field of phycology. The red algae Red algae, or Rhodophyta (, ; ), are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing. The major ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rachis
In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachis'' usually forms the supporting axis of the body and is then called the spine or vertebral column. ''Rachis'' can also mean the central shaft of pennaceous feathers. In the gonad of the invertebrate nematode '' Caenorhabditis elegans'', a rachis is the central cell-free core or axis of the gonadal arm of both adult males and hermaphrodites where the germ cells have achieved pachytene and are attached to the walls of the gonadal tube. The rachis is filled with cytoplasm. In botany In plants, a rachis is the main axis of a compound structure. It can be the main stem of a compound leaf, such as in ''Acacia'' or ferns, or the main, flower-bearing portion of an inflorescence above a supporting peduncle. Where it subdivides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limpet
Limpets are a group of aquatic snails that exhibit a conical shell shape (patelliform) and a strong, muscular foot. Limpets are members of the class Gastropoda, but are polyphyletic, meaning the various groups called "limpets" descended independently from different ancestral gastropods. This general category of conical shell is known as "patelliform" (dish-shaped). All members of the large and ancient marine clade Patellogastropoda are limpets. Within that clade, the members of the Patellidae family in particular are often referred to as "true limpets". Other groups, not in the same family, are also called limpets of one type or another, due to the similarity of their shells' shape. Examples include the Fissurellidae ("keyhole limpet") family, which is part of the Vetigastropoda clade (many other members of the Vetigastropoda do not have the morphology of limpets) and the Siphonariidae ("false limpets"), which use a siphon to pump water over their gills. Behaviour and ecolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discurria Insessa
''Discurria insessa'', common name the seaweed limpet, is a species of sea snail, a true limpet, a marine gastropod mollusk in the family Lottiidae. Description The size of the shell varies between 10 mm and 38 mm. Distribution This marine species occurs from South Alaska to Baja California, Mexico Ecology ''D. insessa'' is believed to live only on ''Egregia menziesii'' (feather boa kelp). Young limpets seem to orient randomly on the stipe but adults are almost always oriented longitudinally along the stipe. ''D. insessa'' feed both on epiphytes and on the ''Egregia'' itself. ''D. insessa'' spawns mainly in spring and summer. There is high mortality during the winter—the largest individuals are usually not more than 1 year old. Larvae settle preferentially on large, crowded, post-reproductive ''Egregia'' and on fronds which already have adults. They grow fastest if they settle on scars made by older limpets. This species runs away quickly if it contacts a seastar s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surfgrass & Feather Boa Kelp, North Moonstone SLO
''Phyllospadix'', surfgrass, is a genus of seagrass, a flowering plant in the family Zosteraceae, described as a genus in 1840. ''Phyllospadix'' grows in marine waters along the coasts of the temperate North Pacific. It is one of the seagrass genera that can perform completely submerged pollination. Species ;Accepted species *'' Phyllospadix iwatensis'' – China, Korea, Japan, Russian Far East *'' Phyllospadix japonicus'' – China, Korea, Japan *'' Phyllospadix juzepczukii'' – Russian Far East *'' Phyllospadix scouleri'' (type species) – Alaska to Baja California *'' Phyllospadix serrulatus'' – Alaska, British Columbia, Washington *''Phyllospadix torreyi'' – British Columbia to northwestern Mexico References * External links Imagesof ''Phyllospadix'' at Algaebase AlgaeBase is a global species database of information on all groups of algae, both marine and freshwater, as well as sea-grass. History AlgaeBase began in March 1996, founded by Michael Gui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fucus
''Fucus'' is a genus of brown algae found in the intertidal zones of rocky seashores almost throughout the world. Description and life cycle The thallus is perennial with an irregular or disc-shaped holdfast or with haptera. The erect portion of the thallus is dichotomous or subpinnately branched, flattened and with a distinct midrib. Gas-filled pneumatocysts (air-vesicles) are present in pairs in some species, one on either side of the midrib. The erect portion of the thallus bears cryptostomata and caecostomata (sterile surface cavities). The base of the thallus is stipe-like due to abrasion of the tissue lateral to the midrib and it is attached to the rock by a holdfast. The gametangia develop in conceptacles embedded in receptacles in the apices of the final branches. They may be monoecious or dioecious. These algae have a relatively simple life cycle and produce only one type of thallus which grows to a maximum size of 2 m. Fertile cavities, the conceptacles, conta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laminaria Digitata
''Laminaria digitata'' is a large brown alga in the family Laminariaceae, also known by the common name oarweed. It is found in the sublittoral zone of the northern Atlantic Ocean. Description ''Laminaria digitata'' is a tough, leathery, dark brown seaweed that grows to two or three metres. The holdfast which anchors it to the rock is conical and has a number of spreading root-like protrusions called rhizoids. The stipe or stalk is flexible and oval in cross section and may be over 1 inch in diameter and grow to 5 feet in length. The blade is large and shaped like the palm of a hand with a number of more or less regular finger-like segments. This seaweed can be distinguished from the rather similar ''Laminaria hyperborea'' by being darker in colour and having a shorter stipe that does not easily snap when bent. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondracanthus Exasperatus
''Chondracanthus exasperatus'', commonly called Turkish towel, is a species of seaweed in the family Gigartinaceae. The specific epithet ' ( lit. 'roughened') refers to the bumpy texture of the blades (leaf-like structures). This texture also leads to the common name which evokes the luxurious feel of a towel from a Turkish bath. The rough, papillae-strewn blade surface even makes it difficult to measure the temperature using infrared thermometers. Description It is a perennial species. Like many species in Gigartinaceae, the appearance of ''C. exasperatus'' can vary depending upon grown conditions. It can be confused with '' Chondracanthus spinosus'' and '' Gigartina binghamiae'', and it might take RFLP analysis to be sure of the species. In addition, the names of the species in the genera '' Gigartina'' and '' Chondracanthus'' have been adjusted several times since 1961. It is also similar to '' Mastocarpus'' species, known as Turkish washcloths, but is smaller, with branch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalassotherapy
Thalassotherapy (from the Greek word ''thalassa'', meaning "sea") is the use of seawater as a form of therapy. Note: Thalasso therapy is a sub-definition under the listing for Thalasso. It also includes the systematic use of sea products and shore climate. Charlier, Roger H. and Marie-Claire P. Chaineux. “The Healing Sea: A Sustainable Coastal Ocean Resource: Thalassotherapy.” ''Journal of Coastal Research'', Number 254:838-856. 2009. There is no scientific evidence that thalassotherapy is effective. History Some claims are made that thalassotherapy was developed in seaside towns in Brittany, France during the 19th century. telegraph.co.uk A particularly prominent practitioner from this er ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buoyancy
Buoyancy (), or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pressure at the bottom of a column of fluid is greater than at the top of the column. Similarly, the pressure at the bottom of an object submerged in a fluid is greater than at the top of the object. The pressure difference results in a net upward force on the object. The magnitude of the force is proportional to the pressure difference, and (as explained by Archimedes' principle) is equivalent to the weight of the fluid that would otherwise occupy the submerged volume of the object, i.e. the displaced fluid. For this reason, an object whose average density is greater than that of the fluid in which it is submerged tends to sink. If the object is less dense than the liquid, the force can keep the object afloat. This can occur only in a no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dawson Turner
Dawson Turner (18 October 1775 – 21 June 1858) was an English banker, botanist and antiquary. He specialized in the botany of cryptogams and was the father-in-law of the botanist William Jackson Hooker. Life Turner was the son of James Turner, head of the Gurney and Turner's Yarmouth Bank; see also: and Elizabeth Cotman, the only daughter of the mayor of Yarmouth, John Cotman. He was educated at North Walsham Grammar School (now Paston College), Norfolk and at Barton Bendish as a pupil of the botanist Robert Forby. He then went to Pembroke College, Cambridge, where the Master was his uncle Rev. Joseph Turner. He however left without a degree due to his father's terminal illness. In 1796, he joined his father's bank. After becoming a banker, he took a more intensive interest in botany in leisure time, collecting specimens in the field. In 1794, Turner offered to help James Sowerby with specimens. Turner published a number of books and collaborated with other botanist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumatocyst
In phycology, a pneumatocyst is a floating structure that contains gas found on brown seaweed. A seaweed's thallus may have more than one. They provide buoyancy to lift the blades toward the surface, allowing them to receive more sunlight for photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored i .... The proportion of gases in the pneumatocysts varies depending on the physiological status of the alga and the partial pressure of gases in the surrounding air or water. The pneumatocyst can hold O2, CO2, N2, and CO. References Further reading Brown algae {{Phaeophyceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
