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The Amaryllidaceae (amaryllids) are a family of herbaceous, mainly perennial and bulbous (rarely rhizomatous) flowering plants included in the monocot order Asparagales. The family takes its name from the genus ''Amaryllis'', hence the common name of the amaryllis family. The leaves are usually linear, the flowers usually bisexual and symmetrical, arranged in umbels on the stem. The petals and sepals are undifferentiated as tepals, which may be fused at the base into a floral tube. Some also display a corona. Allyl sulfide compounds produce the characteristic odour of the onion subfamily (Allioideae). The family, which was originally created in 1805, now contains about 1600 species, divided into about 75 genera, 17 tribes and three subfamilies, the Agapanthoideae (agapanthus), Allioideae (onions and chives) and Amaryllidoideae (amaryllis, daffodils, snowdrops). Over time it has seen much reorganisation and at various times was combined together with the related Liliaceae. Since 2009 a very broad view has prevailed based on phylogenetics, and including a number of other former families. The family are found in tropical to subtropical areas of the world and include many ornamental garden plants and vegetables. == Description == The Amaryllidaceae are mainly terrestrial (rarely aquatic) flowering plants that are herbaceous or succulent geophytes (occasionally epiphytes) that are perennial, with the exception of four species. Most genera grow from bulbs, but a few such as ''Agapanthus'', ''Clivia'' and ''Scadoxus'' develop from rhizomes (underground stems). The leaves are simple rather fleshy and two-ranked with parallel veins. Leaf shape may be linear, strap like, oblong, elliptic, lanceolate (lance shaped) or filiform (threadlike). The leaves which are either grouped at the base or arranged alternatively on the stem may be sessile or petiolate and possess a meristem. The flowers, which are hermaphroditic (bisexual), are actinomorphic (radially symmetrical), rarely zygomorphic, pedicellate or sessile, and are typically arranged in umbels at the apex of leafless flowering stems, or scapes and associated with a filiform (thread like) bract. The perianth (perigonium) consists of six undifferentiated tepals arranged in two whorls of three. The tepals are similar in shape and size, and may be free from each other or fused at the base (connate) to form a floral tube (hypanthium). In some genera, such as Narcissus, this may be surmounted by cup or trumpet shaped projection, the corona (paraperigonium or false corolla). This may be reduced to a mere disc in some species. The position of the ovary varies by subfamily, the Agapanthoideae and Allioideae have superior ovaries, while the Amaryllidoideae have inferior ovaries. There are six stamens arranged in two whorls of three, occasionally more as in ''Gethyllis'' (Amaryllidoideae, 9–18). The fruit is dry and capsule-shaped, or fleshy and berrylike. The Allioideae produce allyl sulfide compounds which give them their characteristic smell. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Amaryllidaceae」の詳細全文を読む スポンサード リンク
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