Iris genus - Iris

...The three upright petals in the center of the corolla are the inner tepals, and between them are the style, which opens flat like petals in three directions, with the pistil at the tip. The stamens are inside the style, and behind them are nectar glands, which are rubbed against pollen when insects crawl under the style. This is how flowers in the Iris genus, including the Iris species, work. Irises come in white flowers, dwarf white flowers commonly known as sansun ayame, purple flowers, and occasionally striped, spotted, wisteria-pink, or branched flowers, as well as six-petaled flowers with inner tepals resembling the outer tepals. ...

*Some of the terminology that refers to the genus "Iris" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…花冠中央に直立した3枚の弁が内花被片で，その間から花弁様に3方に平開しているのは花柱枝で，先端部にめしべがある。おしべは花柱枝の内側にあり，その奥には蜜腺があって，虫が花柱の下へもぐりこむ際に花粉がこすりつけられるのが，アヤメをはじめアヤメ属の花のしくみである。アヤメは白花や通称三寸アヤメと呼ばれる矮性の白花，紫花が見られ，まれに筋入り，斑咲き，藤桃色や分枝するもの，内花被片が外花被片様になった6弁咲きもある。…

※「アヤメ属」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