Polygala

…An evergreen perennial plant of the Polygalaceae family that is commonly found on slightly dry, bright slopes of low mountains (illustration). It is widely distributed from Hokkaido to Okinawa, Korea, China, India, the Himalayas, and the Philippines. It has slender, strong stems that grow in clusters and reach a height of about 10 cm when in flower. After flowering, the stems grow to 20 cm. The leaves are alternate, ovate or oblong, and glossy. They are small, about 1 cm long when in flower, and 3 cm long after flowering. They flower from April to July. They have adorable purple butterfly-shaped flowers that look similar to those of the legume family, in short racemes that emerge from the leaf axils. …

*Some of the terminology that mentions "Polygala" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…低山のやや乾いた明るい斜面にふつうにみられるヒメハギ科の常緑多年草（イラスト）。北海道～沖縄，朝鮮，中国，インド，ヒマラヤ，フィリピンに広く分布する。細く強い茎が束生し，花時の高さは10cm内外。花後，茎は伸長して20cmになる。葉は互生し，卵形または長楕円形で，光沢があり，花時は小さく長さ1cm程度，花後に3cmになる。花期は4～7月ごろ。葉腋（ようえき）から出た短い総状花序に，一見マメ科の花に似た紫色の蝶形花をつけ，愛らしい。…

※「Polygala」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報