|
Cirsonella Densilirata
''Cirsonella densilirata'' is a minute sea snail, a marine gastropod mollusc in the family Skeneidae.Rosenberg, G. (2013). Cirsonella densilirata Suter, 1908. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=598290 on 2013-10-03 Description (Original description by Henry Suter) The height of the shell attains 1.8 mm, its diameter 2.3 mm. The small, white shell has a turbinate shape. It is subdiaphanous, slightly shining, and perforated. Its sculpture consists of numerous fine microscopic spiral lirae. The spire is depressed conoidal. Its outlines are convex, lower than the aperture. The yellowish-white protoconch consists of 2 convex smooth whorls. The 3½ convex whorls are rapidly increasing. The periphery of the body whorl is rounded. The base of the shell is convex, with an impressed umbilical area. The suture is not much impressed. The circular aperture is oblique. Inside it is microscopically lirate. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Suter
Henry Suter (born Hans Heinrich Suter, 9 March 1841 – 31 July 1918) was a Swiss-born New Zealand zoologist, naturalist, palaeontologist, and malacologist. Biography Henry Suter was born on 9 March 1841 in Riesbach, Zurich, Switzerland, and was the son of a prosperous silk-manufacturer of Zurich. He was educated at the local school and university, being trained as an analytical chemist. Suter joined his father's business, and for some years he engaged in various commercial pursuits. From his boyhood, Henry Suter was deeply interested in natural history. He enjoyed the friendship and help of such men as Dr. Auguste Forel, Professor Paul Godet, the brothers de Saussure (linguist Ferdinand de Saussure, Sinolog and astronomer Léopold de Saussure and René de Saussure Esperantist and scientist), Escher von der Linth, and especially the well-known conchologist, Dr. Albert Mousson. Partly to improve his financial prospects and partly lured by the attraction of the fauna of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in numerous gastropods, but it is also found in shelled cephalopods including '' Nautilus'', '' Spirula'' and the large extinct subclass of cephalopods known as the ammonites. A spiral shell can be visualized as consisting of a long conical tube, the growth of which is coiled into an overall helical or planispiral shape, for reasons of both strength and compactness. The number of whorls which exist in an adult shell of a particular species depends on mathematical factors in the geometric growth, as described in D'Arcy Wentworth Thompson's classic 1917 book '' On Growth and Form'', and by David Raup. The main factor is how rapidly the conical tube expands (or flares-out) over time. When the rate of expansion is low, such that each subsequent whorl is not that much wider than the previous one, then the adult shell has numerous whorl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cirsonella
''Cirsonella'' is a genus of small sea snails, marine gastropod molluscs in the family Skeneidae.Bouchet, P.; Gofas, S. (2012). Cirsonella. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=138494 on 2012-05-23 Description (Original description by G. Angas) The minute, smooth shell is globosely turbinate. It is narrowly umbilicated. The aperture is circular. The continuous peristome is slightly thickened. Species Species within the genus ''Cirsonella'' include: * † '' Cirsonella aedicula'' Laws, 1936 * '' Cirsonella africana'' (Bartsch, 1915) * † '' Cirsonella amplector'' Laws, 1944 * '' Cirsonella ateles'' (Dautzenberg & H. Fischer, 1896) * '' Cirsonella carinata'' (Hedley, 1903) * † '' Cirsonella congrua'' (Laws, 1941) * '' Cirsonella consobrina'' Powell, 1930 * '' Cirsonella cubitalis'' (Hedley, 1907) * '' Cirsonella densilirata'' Suter, 1908 * '' Cirsonella extrema'' Thiele, 1912 * '' Cirsonella floridensi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur William Baden Powell
Arthur William Baden Powell (4 April 1901 – 1 July 1987) was a New Zealand malacologist, naturalist and palaeontologist, a major influence in the study and classification of New Zealand molluscs through much of the 20th century. He was known to his friends and family by his third name, "Baden". Biography Early life The name Baden had been a given name in a Powell family since 1731, when Susannah Powell née Thistlethwayte (1696–1762) gave to her child (1731–1792) the maiden name of her mother, Susannah Baden (1663–1692). The name Baden, particularly when associated with the surname Powell, became famous in 1900–1901, the year Arthur William Baden Powell was born, because of the siege of Mafeking, the most famous British action in the Second Boer War, which turned the British commander of the besieged, Robert Baden-Powell, into a national hero. Throughout the British Empire, babies were named after him. No family connection has yet been established between Arthu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Island
The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, and to the south and east by the Pacific Ocean. The South Island covers , making it the world's 12th-largest island. At low altitude, it has an oceanic climate. The South Island is shaped by the Southern Alps which run along it from north to south. They include New Zealand's highest peak, Aoraki / Mount Cook at . The high Kaikōura Ranges lie to the northeast. The east side of the island is home to the Canterbury Plains while the West Coast is famous for its rough coastlines such as Fiordland, a very high proportion of native bush and national parks, and the Fox and Franz Josef Glaciers. The main centres are Christchurch and Dunedin. The economy relies on agriculture and fishing, tourism, and general manufacturing and serv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc. The operculum is attached to the upper surface of the foot and in its most complete state, it serves as a sort of "trapdoor" to close the aperture of the shell when the soft parts of the animal are retracted. The shape of the operculum varies greatly from one family of gastropods to another. It is fairly often circular, or more or less oval in shape. In species where the operculum fits snugly, its outline corresponds exactly to the shape of the aperture of the shell and it serves to seal the entrance of the shell. Many families have opercula that are reduced in size, and which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columella (gastropod)
The columella (meaning "little column") or (in older texts) pillar is a central anatomical feature of a coiled snail shell, a gastropod shell. The columella is often only clearly visible as a structure when the shell is broken, sliced in half vertically, or viewed as an X-ray image. The columella runs from the apex of the shell to the midpoint of the undersurface of the shell, or the tip of the siphonal canal in those shells which have a siphonal canal. If a snail shell is visualized as a cone of shelly material which is wrapped around a central axis, then the columella more or less coincides spatially with the central axis of the shell. In the case of shells that have an umbilicus, the columella is a hollow structure. The columella of some groups of gastropod shells can have a number of plications or folds (the columellar fold, plaits or plicae), which are usually visible when looking to the inner lip into the aperture of the shell. These folds can be wide or narrow, promine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peristome (gastropod)
In the shell of gastropod mollusks (a snail shell), the lip is the free margin of the peristome (synonym: peritreme) or aperture (the opening) of the gastropod shell. In dextral (right-handed) shells (most snail shells are right-handed), the right side or outer side of the aperture is known as the outer lip (''labrum''). The left side of the aperture is known as the inner lip or columellar lip (''labium'') if there is a pronounced lip there. In those species where there is no pronounced lip, the part of the body whorl that adjoins the aperture is known as the parietal wall. The outer lip is usually thin and sharp in immature shells, and in some adults (e.g. the land snails '' Helicella'' and ''Bulimulus''). However, in some other land snails and in many marine species the outer lip is ''thickened'' (also called ''callused''), or ''reflected'' (turned outwards). In some other marine species it is curled inwards (''inflected''), as in the cowries such as '' Cypraea''. It can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture (anatomy)
In anatomy, a suture is a fairly rigid joint between two or more hard elements of an organism, with or without significant overlap of the elements. Sutures are found in the skeletons or exoskeletons of a wide range of animals, in both invertebrates and vertebrates. Sutures are found in animals with hard parts from the Cambrian period to the present day. Sutures were and are formed by several different methods, and they exist between hard parts that are made from several different materials. Vertebrate skeletons The skeletons of vertebrate animals (fish, amphibians, reptiles, birds, and mammals) are made of bone, in which the main rigid ingredient is calcium phosphate. Cranial sutures The skulls of most vertebrates consist of sets of bony plates held together by cranial sutures. These sutures are held together mainly by Sharpey's fibers which grow from each bone into the adjoining one. Sutures in the ankles of land vertebrates In the type of crurotarsal ankle which is fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Whorl
The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the body whorl, or last whorl, is the most recently formed and largest whorl (or revolution) of a spiral or helical shell, terminating in the aperture. It is called the "body whorl" because most of the body of the soft parts of the animal fits into this whorl. The proportional size of the body whorl in gastropod shells differs greatly according to the actual shell morphology. For shells in which the rate of whorl expansion of each revolution around the axis is very high, the aperture and the body whorl are large, and the shell tends to be low spired. The shell of the abalone is a good example of this kind of shell. The opposite tendency can sometimes create a high spire with very little whorl increase per revolution. In these instances ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoconch
A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called "nucleus". The protoconch may sometimes consist of several whorls, but when this is the case, the whorls show no growth lines. The whorls of the adult shell, which are formed after the protoconch, are known as the teleoconch. The teleoconch starts forming when the larval gastropod becomes a juvenile, and the protoconch may dissolve. Quite often there is a visible line of demarcation where the protoconch ends and the teleoconch begins, and there may be a noticeable change in sculpture, or a sudden appearance of sculpture at that point. In some gastropod groups (such as the Architectonicidae), the teleoconch whorls spiral in the opposite direction to the protoconch. In those cases, the shell is called heterostrophic. In species whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Snail
Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the absence of a visible shell. Definition Determining whether some gastropods should be called sea snails is not always easy. Some species that live in brackish water (such as certain neritids) can be listed as either freshwater snails or marine snails, and some species that live at or just above the high tide level (for example species in the genus '' Truncatella'') are sometimes considered to be sea snails and sometimes listed as land snails A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known .... Anatomy Sea snails are a very large group o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> South Island")
_torquata_002.jpg "Click for more on -> Operculum (gastropod)")
.jpg "Click for more on -> Sea Snail")