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Selaginella Watsonii
''Selaginella watsonii'' is a species of spikemoss known by the common name Watson's spikemoss. It is native to the western United States, where it grows in many rocky habitat types, including high mountain peaks in alpine climates. This lycophyte forms mats or cushions of short, forking stems. They are lined with linear or lance-shaped leaves no more than 4 millimeters long, often tipped with tiny bristles. The strobili A strobilus (plural: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem. Strobili are often called cones, but some botanists restrict the use of the term cone to th ... containing the reproductive structures are 1 to 3 centimeters long. References External linksJepson Manual Treatment [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lucien Marcus Underwood
Lucien Marcus Underwood (October 26, 1853 – November 16, 1907) was an American botanist and mycologist of the 19th and early 20th centuries. Early life and career He was born in New Woodstock, New York. He enrolled at Syracuse University in 1873 and graduated in 1877. He earned his masters in 1878 and finally and completed his PhD in 1879 under Alexander Winchell. During his graduate school, he taught at Cazenovia Seminary for two years. After a year's teaching at Hedding College, in 1880 he was appointed professor of geology and botany in Illinois Wesleyan University. In 1883, he was appointed professor of geology, botany, and zoology at Syracuse. In 1890, he accepted the Morgan Fellowship at Harvard University to study the Sullivant and Taylor collection of hepatics. In 1891 he became professor of botany in De Pauw University. In 1896, after one year stint as a biology professor at Alabama Polytechnic Institute (''Auburn''), Underwood became a professor of botany at Colu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selaginella
''Selaginella'' is the sole genus of vascular plants in the family Selaginellaceae, the spikemosses or lesser clubmosses. This family is distinguished from Lycopodiaceae (the clubmosses) by having scale-leaves bearing a ligule and by having spores of two types. They are sometimes included in an informal paraphyletic group called the "fern allies". '' S. moellendorffii'' is an important model organism. Its genome has been sequenced by the United States Department of Energy's Joint Genome Institute. The name ''Selaginella'' was erected by Palisot de Beauvois solely for the species ''Selaginella selaginoides'', which turns out (with the closely related ''Selaginella deflexa'') to be a clade that is sister to all other ''Selaginellas'', so any definitive subdivision of the species into separate genera leaves two taxa in ''Selaginella'', with the hundreds of other species in new or resurrected genera. ''Selaginella'' occurs mostly in the tropical regions of the world, with a hand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpine Climate
Alpine climate is the typical weather (climate) for elevations above the tree line, where trees fail to grow due to cold. This climate is also referred to as a mountain climate or highland climate. Definition There are multiple definitions of alpine climate. In the Köppen climate classification, the alpine and mountain climates are part of group ''E'', along with the polar climate, where no month has a mean temperature higher than . According to the Holdridge life zone system, there are two mountain climates which prevent tree growth : a) the alpine climate, which occurs when the mean biotemperature of a location is between . The alpine climate in Holdridge system is roughly equivalent to the warmest tundra climates (ET) in the Köppen system. b) the alvar climate, the coldest mountain climate since the biotemperature is between 0 °C and 1.5 °C (biotemperature can never be below 0 °C). It corresponds more or less to the coldest tundra climates and to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lycopodiophyta
The lycophytes, when broadly circumscribed, are a vascular plant (tracheophyte) subgroup of the kingdom Plantae. They are sometimes placed in a division Lycopodiophyta or Lycophyta or in a subdivision Lycopodiophytina. They are one of the oldest lineages of extant (living) vascular plants; the group contains extinct plants that have been dated from the Silurian (ca. 425 million years ago). Lycophytes were some of the dominating plant species of the Carboniferous period, and included tree-like species, although extant lycophytes are relatively small plants. The scientific names and the informal English names used for this group of plants are ambiguous. For example, "Lycopodiophyta" and the shorter "Lycophyta" as well as the informal "lycophyte" may be used to include the extinct zosterophylls or to exclude them. Description Lycophytes reproduce by spores and have alternation of generations in which (like other vascular plants) the sporophyte generation is dominant. Some lycophyte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strobilus
A strobilus (plural: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem. Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers. Strobili are characterized by a central axis (anatomically a stem) surrounded by spirally arranged or decussate structures that may be modified leaves or modified stems. Leaves that bear sporangia are called ''sporophylls'', while sporangia-bearing stems are called '' sporangiophores''. Lycophytes Some members of both of the two modern classes of Lycopodiophyta (Lycopodiopsida and Isoetopsida) produce strobili. In all cases, the lateral organs of the strobilus are microphylls, bearing sporangia. In other lycophytes, ordinary foliage leaves can act as sporophylls, and there are no organized strobili. Diphasiastrum complanatum strobilus (01).jpeg, Strobili of ''Diphasiastrum'' Lycopodium saururus.JPG, St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
