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Isoëtes Echinospora
''Isoetes echinospora'', also known as spiny quillwort, spiny-spored quillwort or spring quillwort is a species of quillwort in the Isoetaceae family, and is the most abundant species in Canada. It can be found in shallow aquatic environments from Labrador and Newfoundland to Alaska, and south to Pennsylvania, Wisconsin, Michigan, Colorado, and California. In Germany it is found in only two locations: the Feldsee and Lake Titisee, both in the High Black Forest.Information Board at the Feldsee. Recorded on 26 Aug 2015. It bears 10–30 green to yellow leaves and a two-lobed corm. The velum covers one to three quarters of the sporangium, which are long. Round white megaspores are about in diameter and are covered with spines. Kidney-shaped microspore Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quillwort
''Isoetes'', commonly known as the quillworts, is a genus of lycopod. It is the only living genus in the family Isoetaceae and order Isoetales. , there were about 200 recognized species, with a cosmopolitan distribution mostly in aquatic habitats but with the individual species often scarce to rare. Species virtually identical to modern quillworts have existed since the Jurassic epoch, though the timing of the origin of modern ''Isoetes'' is subject to considerable uncertainty. The name of the genus may also be spelled ''Isoëtes''. The diaeresis (two dots over the e) indicates that the o and the e are to be pronounced in two distinct syllables. Including this in print is optional; either spelling (''Isoetes'' or ''Isoëtes'') is correct. Description Quillworts are mostly aquatic or semi-aquatic in clear ponds and slow-moving streams, though several (e.g. '' I. butleri'', '' I. histrix'' and '' I. nuttallii'') grow on wet ground that dries out in the summer. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoetaceae
Isoetaceae is a family including living quillworts ('' Isoetes'') and comparable extinct herbaceous lycopsids ('' Tomiostrobus''). References External links * * Lycophytes Plant families {{Lycophyte-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feldsee
The Feldsee (also ''Feldbergsee'') is a lake in southern Baden-Württemberg at the foot of the Feldberg east of Freiburg im Breisgau in Germany. It is part of the Southern Black Forest Nature Park. Geology and earth history The Feldsee is a tarn, around 97,500 m2 in area and up to 32 metres deep. It was formed by glaciers of the last ice age. The largest tarn in the Black Forest, it is hemmed in on three sides by steep mountainsides up to 300 metres high. It is almost circular and has a diameter of between 350 and 370 metres. This area of highland at a height of , which is open to the northeast, enabled it to amass and retain the huge quantities of snow that were the cause of this armchair-shaped terrain with its steep back face, level floor and embankment of moraine at the front. The lake formed after the melting of the ice sheet behind the lines of heaped-up glacial debris. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titisee
The Titisee is a lake in the southern Black Forest in Baden-Württemberg. It covers an area of and is an average of deep. It owes its formation to the Feldberg glacier, the moraines of which were formed in the Pleistocene epoch and nowadays form the shores of the lake. The lake's outflow, at above sea level, is the River Gutach, which merges with the Haslach stream below Kappel to form the Wutach. The waters of the Titisee thus drain eventually into the Upper Rhine between Tiengen and Waldshut. On the north shore lies the spa town of the same name, today a part of the municipality of Titisee-Neustadt. History A glacial lake is created when the glacier remains stationary for a long time and the weight of the glacier excavates the landscape. Where the glacier is less powerful, the subsoil is less excavated and rises. In addition, it is possible that a moraine (deposit of rock material that is transported with the glacier) prevents the runoff. When the ice melts, water is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Forest
The Black Forest ( ) is a large forested mountain range in the States of Germany, state of Baden-Württemberg in southwest Germany, bounded by the Rhine Valley to the west and south and close to the borders with France and Switzerland. It is the source of the Danube and Neckar rivers. Its highest peak is the Feldberg (Black Forest), Feldberg with an elevation of above sea level. Roughly oblong in shape, with a length of and breadth of up to , it has an area of about . Historically, the area was known for forestry and the mining of ore deposits, but tourism has now become the primary industry, accounting for around 300,000 jobs. There are Baroque fortifications in the Black Forest, several ruined military fortifications dating back to the 17th century. History In ancient times, the Black Forest was known as , after the Celtic deity, Abnoba. In Roman times (Late antiquity), it was given the name ("Marcynian Forest", from the Germanic word ''marka'', "border"). The Black ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corm
Corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen, underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word ''cormous'' usually means plants that grow from corms, parallel to the terms ''tuberous'' and ''bulbous'' to describe plants growing from tubers and bulbs. A corm consists of one or more Internode (botany), internodes with at least one growing point, generally with protective leaves modified into skins or Tunica (biology), tunics. The tunic of a corm forms from dead Petiole (botany), petiole sheaths—remnants of leaves produced in previous years. They act as a covering, protecting the corm from insects, digging animals, flooding, and water loss. The tunics of some species are thin, dry, and papery, at least in young plants, however, in some families, such as ''Iridaceae'', the tunic of a mature corm can be formidable protection. For exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velum (botany)
A veil or velum, in mycology, is one of several structures in fungi, especially the thin membrane that covers the cap and stalk of an immature mushroom. Encarta Dictionary Veils fall into two categories: * Partial veil
In mycology, a partial veil (also called an inner veil, to differentiate it from the "outer", or universal veil) is a temporary structure of tissue found on the fruiting bodies of some Basidiomycota, basidiomycete fungus, fungi, typically agarics. ...
* Universal veil
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Sporangium
A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many other groups form sporangia at some point in their biological life cycle, life cycle. Sporangia can produce spores by mitosis, but in land plants and many fungi, sporangia produce genetically distinct haploid spores by meiosis. It's outdated name, sporange, is one of the few perfect rhymes for Orange (colour), orange. Fungi In some phyla of fungi, the sporangium plays a role in asexual reproduction, and may play an indirect role in sexual reproduction. The sporangium forms on the sporangiophore and contains Ploidy, haploid Cell nucleus, nuclei and cytoplasm. Spores are formed in the sporangiophore by encasing each haploid nucleus and cytoplasm in a tough outer membrane. During asexual reproduction, these spores are dispersed via wind and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megaspore
Megaspores, also called macrospores, are a type of spore that is present in heterosporous plants. These plants have two spore types, megaspores and microspores. Generally speaking, the megaspore, or large spore, germinates into a female gametophyte, which produces egg cells. These are fertilized by sperm produced by the male gametophyte developing from the microspore. Heterosporous plants include seed plants (gymnosperms and flowering plants), water ferns (Salviniales), spikemosses (Selaginellaceae) and quillworts (Isoetaceae). Megasporogenesis In gymnosperms and flowering plants, the megaspore is produced inside the nucellus of the ovule. During megasporogenesis, a diploid precursor cell, the megasporocyte or megaspore mother cell, undergoes meiosis to produce initially four haploid cells (the megaspores). Angiosperms exhibit three patterns of megasporogenesis: monosporic, bisporic, and tetrasporic, also known as the ''Polygonum'' type, the ''Alisma'' type, and the ''Drusa'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microspore
Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote. Megaspores are structures that are part of the alternation of generations in many seedless vascular cryptogams, all gymnosperms and all angiosperms. Plants with heterospory, heterosporous life cycles using microspores and megaspores arose independently in several plant groups during the Devonian period. Microspores are haploid, and are produced from diploid microsporocytes by meiosis. Morphology The microspore has three different types of wall layers. The outer layer is called the perispore, the next is the exospore, and the inner layer is the endospore. The perispore is the thickest of the three layers while the exospore and endospore are relatively equal in width. Seedless vascular plants In heterosporous seedless vascular plants, modified ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isoetes
''Isoetes'', commonly known as the quillworts, is a genus of lycopod. It is the only living genus in the family Isoetaceae and order Isoetales. , there were about 200 recognized species, with a cosmopolitan distribution mostly in aquatic habitats but with the individual species often scarce to rare. Species virtually identical to modern quillworts have existed since the Jurassic epoch, though the timing of the origin of modern ''Isoetes'' is subject to considerable uncertainty. The name of the genus may also be spelled ''Isoëtes''. The diaeresis (two dots over the e) indicates that the o and the e are to be pronounced in two distinct syllables. Including this in print is optional; either spelling (''Isoetes'' or ''Isoëtes'') is correct. Description Quillworts are mostly aquatic or semi-aquatic in clear ponds and slow-moving streams, though several (e.g. '' I. butleri'', '' I. histrix'' and '' I. nuttallii'') grow on wet ground that dries out in the summer. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flora Of Northern America
Flora (: floras or florae) is all the plant life present in a particular region or time, generally the naturally occurring ( indigenous) native plants. The corresponding term for animals is ''fauna'', and for fungi, it is '' funga''. Sometimes bacteria and fungi are also referred to as flora as in the terms ''gut flora'' or ''skin flora'' for purposes of specificity. Etymology The word "flora" comes from the Latin name of Flora, the goddess of plants, flowers, and fertility in Roman mythology. The technical term "flora" is then derived from a metonymy of this goddess at the end of the sixteenth century. It was first used in poetry to denote the natural vegetation of an area, but soon also assumed the meaning of a work cataloguing such vegetation. Moreover, "Flora" was used to refer to the flowers of an artificial garden in the seventeenth century. The distinction between vegetation (the general appearance of a community) and flora (the taxonomic composition of a community) wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
