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Water Stargrass
''Heteranthera dubia'', commonly called water stargrass or grassleaf mudplantain, is a species of aquatic plant in the pickerel-weed family (Pontederiaceae). It is native to North and Central America where it is widespread from Canada to Guatemala. It lives submerged in freshwater such as rivers and lakes. It can be found as deep as 5.5 meters, to as shallow as stranded on the shoreline. It is most abundant in alkaline waters. ''Heteranthera dubia'' is a perennial with much variation in its appearance. The leaves are different sizes and shapes across individuals, partly genetic variation and partly response to water conditions, for example, the speed and turbulence of surrounding currents. Submersed individuals also have a different stem and leaf morphology from those that occur partially or completely out of the water. Its inflorescence bears a single short-lived flower that blooms in the morning and wilts in the evening. It has six yellow perianth parts each less than a centim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Nikolaus Joseph Von Jacquin
Nikolaus Joseph Freiherr von Jacquin (16 February 172726 October 1817) was a scientist who studied medicine, chemistry and botany. Biography Born in Leiden in the Netherlands, he studied medicine at Leiden University, then moved first to Paris and afterward to Vienna. In 1752, he studied under Gerard van Swieten in Vienna. Between 1755 and 1759, Jacquin was sent to the West Indies, Central America, Venezuela and New Granada by Francis I, Holy Roman Emperor, Francis I to collect plants for the Schönbrunn Palace, and amassed a large collection of animal, plant and mineral samples. In 1797, Alexander von Humboldt profited from studying these collections and conversing with Jacquin in preparation of his own journey to the Americas. In 1763, Jacquin became professor of chemistry and mineralogy at the Mining Academy (Banská Štiavnica), Bergakademie Schemnitz (now Banská Štiavnica in Slovakia). In 1768, he was appointed Professor of Botany and Chemistry and became director of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
