From today's featured articleImperator torosus, the brawny bolete, is a fungus in the family Boletaceae. Native to southern Europe, the Caucasus and Israel, it is generally associated with deciduous trees such as hornbeam, oak and beech in warm, dry locales. Although generally rare in Europe, it appears to be relatively common in Hungary. Appearing in summer and autumn on chalky soils, the stocky mushrooms have an ochre cap up to 20 cm (8 in) across, yellow pores on the cap underside, and a wine-red to brown or blackish stalk up to 6–15 cm (2.4–5.9 in) long by 3–6 cm (1.2–2.4 in) wide. The pale yellow flesh changes colour when broken or bruised depending on age; younger mushrooms become reddish, and older ones take on bluish tones. Swedish mycologists Elias Magnus Fries and Christopher Theodor Hök described this species as Boletus torosus in 1835, relying in part on the work of Louis Secretan. Eating raw, or sometimes even cooked, mushrooms of this species leads to vomiting and diarrhea. (Full article...)
Recently featured:
Did you know...
|
In the news
On this day
George Byng, 1st Viscount Torrington (b. 1663) · Eunice Hale Waite Cobb (b. 1803) · Paul Zorner (d. 2014)
More anniversaries:
|
Today's featured picture
![]() |
Sonar, an acronym for SOund NAvigation (and) Ranging, is a technique that uses sound propagation to communicate with or detect objects on or under the surface of a body of water. The first recorded use of the technique was by Leonardo da Vinci in 1490 via a tube inserted into the water to detect vessels by ear. Sonar equipment was developed during World War I to counter the growing threat of submarine warfare; an operational passive sonar system, which only listens for the sound of vessels, was in use by 1918. Modern active sonar systems use an acoustic transponder to generate a sound wave which is then reflected back from target objects. This picture shows a sonar image of the Soviet Navy minesweeper T-297, formerly the Latvian Virsaitis, that was shipwrecked on 3 December 1941 in the Gulf of Finland. Image: Tuukritööde OÜ
Recently featured:
|
Other areas of Wikipedia
- Community portal – Bulletin board, projects, resources and activities covering a wide range of Wikipedia areas.
- Help desk – Ask questions about using Wikipedia.
- Local embassy – For Wikipedia-related communication in languages other than English.
- Reference desk – Serving as virtual librarians, Wikipedia volunteers tackle your questions on a wide range of subjects.
- Site news – Announcements, updates, articles and press releases on Wikipedia and the Wikimedia Foundation.
- Village pump – For discussions about Wikipedia itself, including areas for technical issues and policies.
Wikipedia's sister projects
Wikipedia is hosted by the Wikimedia Foundation, a non-profit organization that also hosts a range of other projects:
Free media repository
Wiki software development
Wikimedia project coordination
Free textbooks and manuals
Free knowledge base
Free-content news
Collection of quotations
Free-content library
Directory of species
Free learning materials and activities
Free travel guide
Dictionary and thesaurus