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Lecthaylus
''Lecthaylus'' is a genus of fossil sipunculid worms that lived between the Cambrian and the Lower Carboniferous periods. Sipunculid worms are sedentary marine worms without any mineralised parts, and for this reason are very rare in the fossil record. ''Lecthaylus gregarius'' was described by the American geologist and palaentologist Stuart Weller in 1925 from the Silurian strata near Chicago. Professor Weller described this worm, which was abundant in the deposits, as being "manifestly related to '' Serpulites'' or '' Conularia''; however, further examination by Sharat Kumar Roy determined that this was not the case, and that the worms were more likely members of Sipunculoidea, and this is now the accepted position. A related species of sipunculan was discovered in 2007 in the Granton Shrimp Bed The Granton Shrimp Bed is a fossil-bearing deposit exposed on the southern shore of the Firth of Forth near Edinburgh, in Scotland. It is classified as a Konservat-Lagerstätten b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sipuncula
The Sipuncula or Sipunculida (common names sipunculid worms or peanut worms) is a class containing about 162 species of unsegmented marine annelid worms. The name ''Sipuncula'' is from the genus name ''Sipunculus'', and comes from the Latin ''siphunculus'' meaning a "small tube". Sipuncula was once considered a phylum, but was demoted to a class of Annelida, based on recent molecular work. Sipunculans vary in size but most species are under in length. The body is divided into an unsegmented, bulbous trunk and a narrower, anterior section, called the "introvert", which can be retracted into the trunk. The mouth is at the tip of the introvert and is surrounded in most groups by a ring of short tentacles. With no hard parts, the body is flexible and mobile. Although found in a range of habitats throughout the world's oceans, the majority of species live in shallow water habitats, burrowing under the surface of sandy and muddy substrates. Others live under stones, in rock crevic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sipunculans
The Sipuncula or Sipunculida (common names sipunculid worms or peanut worms) is a class containing about 162 species of unsegmented marine annelid worms. The name ''Sipuncula'' is from the genus name ''Sipunculus'', and comes from the Latin ''siphunculus'' meaning a "small tube". Sipuncula was once considered a phylum, but was demoted to a class of Annelida, based on recent molecular work. Sipunculans vary in size but most species are under in length. The body is divided into an unsegmented, bulbous trunk and a narrower, anterior section, called the "introvert", which can be retracted into the trunk. The mouth is at the tip of the introvert and is surrounded in most groups by a ring of short tentacles. With no hard parts, the body is flexible and mobile. Although found in a range of habitats throughout the world's oceans, the majority of species live in shallow water habitats, burrowing under the surface of sandy and muddy substrates. Others live under stones, in rock crevic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lower Carboniferous
Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is situated about five miles south west of Dursley, eighteen miles southwest of Gloucester and fifteen miles northeast of Bristol. Lower Wick is within the civil ... Gloucestershire, England See also * Nizhny {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stuart Weller
Stuart Weller (26 December 1870, Maine, New York – 1927) was an American paleontologist and geologist. Weller studied geology and paleontology at Cornell University with bachelor's degree in 1894 and at Yale University with Ph.D. in 1901. Beginning in 1895 he worked at the University of Chicago, where in 1897–1900 he was a research associate, and became in 1900 Instructor, in 1902 Assistant Professor, in 1908 Associate Professor and in 1915 Professor of Paleontology and Geology. It is noteworthy to mention that Weller supervised Grace Anne Stewart, the first Canadian female to earn a B.A. majoring in geology, as she earned her Ph.D. from the University of Chicago. In 1897 he married; the marriage produced three sons. From 1919 until his death, in addition to his professorship, he was the director of the Walker Museum at the University of Chicago. In 1926 he was the president of the Paleontological Society The Paleontological Society, formerly the Paleontological Societ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siluria
The Silures ( , ) were a powerful and warlike tribe or tribal confederation of ancient Britain, occupying what is now south east Wales and perhaps some adjoining areas. They were bordered to the north by the Ordovices; to the east by the Dobunni; and to the west by the Demetae. Origins According to Tacitus's biography of Agricola, the Silures usually had a dark complexion and curly hair. Due to their appearance, Tacitus believed they had crossed over from Spain at an earlier date."... the swarthy faces of the Silures, the curly quality, in general, of their hair, and the position of Spain opposite their shores, attest to the passage of Iberians in old days and the occupation by them of these districts; ..." (Tacitus Annales Xi.ii, translated by M. Hutton) Jordanes, in his Origins and Deeds of the Goths, describes the Silures. "The Silures have swarthy features and are usually born with curly black hair, but the inhabitants of Caledonia have reddish hair and large loose-joint ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chicago
(''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = Country , subdivision_name = United States , subdivision_type1 = State , subdivision_type2 = Counties , subdivision_name1 = Illinois , subdivision_name2 = Cook and DuPage , established_title = Settled , established_date = , established_title2 = Incorporated (city) , established_date2 = , founder = Jean Baptiste Point du Sable , government_type = Mayor–council , governing_body = Chicago City Council , leader_title = Mayor , leader_name = Lori Lightfoot ( D) , leader_title1 = City Clerk , leader_name1 = Anna Valencia ( D) , unit_pref = Imperial , area_footnotes = , area_tot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granton Shrimp Bed
The Granton Shrimp Bed is a fossil-bearing deposit exposed on the southern shore of the Firth of Forth near Edinburgh, in Scotland. It is classified as a Konservat-Lagerstätten because of the exceptional quality of preservation of the fossils and is dominated by crustaceans; the deposit dates back to the Lower Carboniferous, some 359 to 323 million years ago. Location and geological setting The Granton Shrimp Bed is located on the south shore of the Firth of Forth about from the centre of Edinburgh. It consists of a layer of dolomitic limestone surrounded by Dinantian mud shales which were formed as a result of the deposit of material in either a delta plain setting or in an inter-distributary bay, where sedimentation occurred because of flood-generated incursions. The shrimp bed resulted from the periodic inundations of marine water into stagnant lagoons, each incursion leaving a lamina of limestone rich in the fossils of soft-bodied marine invertebrates and other animals. T ... [...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] |
