Sphenophyllales
The horsetails and their fossil relatives have long been recognized as distinct from other seedless vascular plants, such as the ferns (Polypodiopsida). Before the advent of modern molecular studies, the relationship of this group to other living and fossil plants was considered problematic. Because of their unclear relationships, the rank botanists assigned to the horsetails varied from order to division. When recognized as a separate division, the literature uses many possible name… Web商品名称、作者、出版社、isbn. 搜索历史. 搜索
Sphenophyllales
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WebWood development and cambial activity in the Carboniferous articulate stem Sphenophyllum plurifoliatum Williamson and Scott were studied by analyzing mature interfascicular secondary xylem. The wood parenchyma is interpreted as being a true vascular-ray system. Rays are mostly biseriate and appear as groups of cells in the … WebSphenophyllales. The name of this sub-group is derived from their wedge-shaped leaves. The narrow ends of the wedges forming the points of junction with the stems. Fossil example: Sphenophyllum. Detached cones may be assigned to: Bowmanites, Litostrobus, Peltastrobus, Sphenostrobus, Cheirostrobus.
Web图片来源：维管束植物系统发育–维管束植物-系统学和性状，2024. 苔藓植物分为三类：苔类、藓类和角苔类。 目前的研究偏向于认为苔藓植物是一个单系群，即它们独自成一个类群，过去有观点认为苔类与维管植物亲缘关系更远，角苔类或藓类与维管植物亲缘关系更近。 WebApr 3, 2012 · A new species, Psygmophyllum intermedium, sp. nov., is described based on macromorphological and epidermal and cuticular characters. The main patterns of the intraspecific (intrapopulational and ontogenetic) variability of the P. intermedium leaves are established. A new combination, Psygmophyllum interruptepinnatum (Kutorga) …
Webthe ventral sporangiophore of the Sphenophyllales. T I propose to adduce evidence to show that whilst Professor Bower's view that the whole fertile structure of Tmesipteris is … Webthe ventral sporangiophore of the Sphenophyllales. t I propose to adduce evidence to show that whilst Professor Bower’s view that the whole fertile structure of Tmesipteris is equivalent to a single leaf is correct, Dr. Scott’s suggestion that the synangium, with its axis, corresponds to a ventral sporangiophore, is also correct.
WebMay 22, 2024 · Gondwana flora is a collection of continents including Australia, Antarctica, Africa, South America, and India (Fig 1). This supercontinent was once a unity and finally broke up during the Mesozoic era. The above-mentioned masses of land share common stratigraphic features like fossils and sediments as there was easy and free migration of …
WebSphenophytes, fossil and living, characteristically have whorled leaves and branches and conspicuously jointed stems, which in many cases are also ribbed. Reproductive … haveri karnataka 581110Webnoun. : a genus of Paleozoic fossil plants that are related to the club mosses and horsetails but are usually placed in the separate order Sphenophyllales, that have jointed stems, … haveri to harapanahalliWebRetusotriletes -type spores are reported in situ for the first time within sphenophytes, having previously been found within rhyniophytes, zosterophylls, trimerophytes, and algae, further emphasizing the polyphletic nature of the genus and convergent spore evolution across multiple lineages. haveriplats bermudatriangelnWebUnsourced material may be challenged and removed. Fossil leaves and branches of the species Sphenophyllum miravallis, Upper Carboniferous. Collection of the Universiteit Utrecht . Sphenophyllum is a genus in the order Sphenophyllales. havilah residencialWebIn contrast to fertile organs demonstrating great diversity in bract shape, structure, and sporangiophore number, the stelar architecture of the Sphenophyllales is consistent in … havilah hawkinsWebSPHENOPHYLLALES [CH. more usual type of strobilus; instead of the dorsal and ventral lobes of the bracts sharing between them the duties of protec- tion and spore-production, the whole of each bract is constructed on the plan of the maximum spore-output, the laminar termina- tions of the sporangiophores serving the purpose of protection. haverkamp bau halternWebThe fructifications of the Sphenophyllales are cones consisting of superposed whorls of sporophylls. There are five principal types of sporophyll; firstly there is the ill-understood type of Spheizophyllzm majus and S. trichomatosum, in which one or more sporangia appear to be situated on the upper surface of the divided have you had dinner yet meaning in punjabi