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Dawsonia Stem
''Dawsonia'' is the scientific name of several genera of organisms and may refer to: * ''Dawsonia'' (plant), a genus of moss some reaching up to 65 cm (two feet) in length * ''Dawsonia'' (trilobite), an eodiscoid trilobite * ''Dawsonia'' (problematicum), a Palaeozoic problematicum {{Genus disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dawsonia (plant)
''Dawsonia'' is a genus of acrocarpous mosses. ''Dawsonia'', along with other members of the order Polytrichales, are taller than most mosses and have thicker leaves. Their sporophytes have conducting systems analogous to those of vascular plants. '' Dawsonia superba'' is found in New Zealand, Australia and New Guinea. '' D. longifolia'' is found in the Philippines, Indonesia, Malaysia, and Australia. There is uncertainty as to whether ''D. superba'' and ''D. longifolia'' are actually distinct species. Etymology ''Dawsonia'' was named in honor of Dawson Turner (1775–1858), distinguished cryptogamist and friend of Robert Brown, who named the genus in 1811. Description Height Moss gametophytes lack internal transport tissues, which, coupled with the absence of cuticles, leads to the water-loss characteristic of bryophytes. As bryophytes can only grow when hydrated, the lack of conducting tissue restricts most mosses, even in relatively wet habitats, to a low stature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dawsonia (trilobite)
''Dawsonia'' is the scientific name of several genera of organisms and may refer to: * ''Dawsonia'' (plant), a genus of moss some reaching up to 65 cm (two feet) in length * ''Dawsonia'' (trilobite), an eodiscoid trilobite * ''Dawsonia'' (problematicum), a Palaeozoic problematicum {{Genus disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eodiscina
Eodiscina is trilobite suborder. The Eodiscina first developed near the end of the Lower Cambrian period (late Atdabanian) and became extinct at the end of the Middle Cambrian. Species are tiny to small, and have a thorax of two or three segments. Eodiscina includes six families classified under one superfamily, Eodiscoidea. Taxonomy The Eodiscina are mostly considered the more primitive suborder of the Agnostida, and the Agnostina the more advanced. Some scholars do not consider the Agnostina true trilobites, and consequently rejected the idea that they were related to the Eodiscina. Consequently, these scientists have proposed to elevate the group to ordinal level, which would thus be called Eodiscida Kobayashi, 1939. Origin The oldest known eodiscoid is '' Tsunyidiscus''. The glabella of ''Tsunyidiscus'' is extremely similar to that of ''Dipharus clarki'', and distinct from all other eodiscoids. ''D. clarki'' is thought to represent an immature stage of the redlichioid ''B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |