Asclepias - Asclepias

A perennial vine in the Asclepiadaceae family (APG classification: Apocynaceae). It has a long underground stem, and when the stem or leaves are damaged, a white milky liquid comes out. The leaves are opposite, long egg-shaped and heart-shaped, with a whitish-green underside. In July and August, the flower stalk extends from the axils, higher than the leaves, and pale purple flowers bloom. The corolla is deeply divided into five lobes, and the inner surface of the lobes is densely hairy. The fruit is large and broadly lanceolate, with protuberances on the surface, and the seeds have long white hairs. It grows in the hilly and mountainous plains from Hokkaido to Kyushu, and is widely distributed from the temperate to subtropical regions of East Asia. The seeds and leaves are dried for medicinal purposes, and the seed hairs were once used as a substitute for cotton. The old name for this plant was Kagami, which is said to be a derivative of Kagamiimo. The Asclepiad genus has inflorescences that are mostly racemose, with the corona shorter than the style and a long horn-like protrusion on the stigma. There are six species in East Asia, one of which is found in Japan.

[Hideo Takahashi June 21, 2021]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

ガガイモ科（APG分類：キョウチクトウ科）の多年生つる草。長い地下茎があり、茎や葉を傷つけると白い乳液が出る。葉は対生し、長卵状心臓形で、裏面は白緑色である。7～8月、葉腋(ようえき)に、葉より高く花柄を伸ばし、淡紫色の花を開く。花冠は深く5裂し、裂片の内面は密に毛がある。果実は大形で広披針(こうひしん)形、表面に突起があり、種子には白色の長毛がある。北海道から九州の丘陵帯から山地帯の原野に生え、東アジアの温帯から亜熱帯に広く分布する。種子や葉を乾燥して薬用とし、かつて種子の毛は綿の代用とした。名は、古名をカガミといい、カガミイモの転じたものという。ガガイモ属は花序が多くは総状をなし、副花冠は蕊柱(ずいちゅう)よりも短く、柱頭に長い角状突起がある。東アジアに6種あり、そのうち日本に1種が分布する。

［高橋秀男　2021年6月21日］

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