《中国植物志》|| 雨久花科 PONTEDERIACEAE ||雨久花属 Monochoria Presl ||雨久花 Monochoria korsakowii Regel & Maack

1.雨久花（秘传花镜）图版32: 7-10
Monochoria korsakowii Regel et Maack in Mem. Acad. Petersb. 4 (4) : 155. 1861; Hance in Journ. Linn. Soc. Bot. 13: 88. 1872; Franch., Pl. David. 1: 310. 1883; N. E. Brown in Journ. Linn. Soc. Bot. 36: 149. 1903; 中国高等植物图鉴5: 405. 图7639. 1976.; 秦岭植物志1 (1) : 296. 图266-1976. ----M. ovata Kunth, Enum. Pl. 4: 665. 1843; ——M. vaginalis Presl var. korsakowii (Regel et Maack) Solms in DC Monogr. Phanerog. 4: 525. 1883.
直立水生草本；根状茎粗壮，具柔软须根。茎直立，高30-70厘米，全株光滑无毛，基部有时带紫红色。叶基生和茎生；基生叶宽卵状心形，长4-10厘米，宽3-8厘米，顶端急尖或渐尖，基部心形，全缘，具多数弧状脉；叶柄长达30厘米，有时膨大成囊状；茎生叶叶柄渐短，基部增大成鞘，抱茎。总状花序顶生，有时再聚成圆锥花序；花10余朵，具5-10毫米长的花梗；花被片椭圆形，长10-14毫米，顶端圆钝，蓝色；雄蕊6枚，其中1枚较大，花药长圆形，浅蓝色，其余各枚较小，花药黄色，花丝丝状。蒴果长卵圆形，长10-12毫米。种子长圆形，长约1.5毫米，有纵棱。花期7-8月，果期9-10月。
产东北、华北、华中、华东和华南。生于池塘、湖沼靠岸的浅水处和稻田中。朝鲜、日本、俄罗斯西伯利亚地区也有分布。
全草可作家畜、家禽饲料；花美丽，可供观赏。

《Flora of China》|| Pontederiaceae || Monochoria ||雨久花 Monochoria korsakowii

1. Monochoria korsakowii Regel & Maack in Regel, Mém. Acad. Imp. Sci. Saint Pétersbourg, sér. 7. 4(4): 155. 1861.

雨久花 yu jiu hua

Monochoria vaginalis (N. L. Burman) C. Presl ex Kunth var. korsakowii (Regel & Maack) Solms.

Herbs aquatic, glabrous. Vegetative stems stout. Leaves radical or alternate and cauline. Radical leaves to 30 cm; leaf blade broadly cordate to ovate-cordate, 4--10 × 3--8 cm, densely veined, base cordate with basal lobes rounded, margin entire, apex acute to acuminate. Flowering stems erect, 30--70 cm, base sometimes purplish red. Inflorescences remaining erect after anthesis, racemose to paniculate, 10--20-flowered or more. Pedicels 5--10 mm. Perianth segments blue, elliptic, 1.2--2 cm, apex obtuse. Larger stamen: filament appendaged; anther 4--5.2 mm. Smaller stamens: filament filiform; anthers 2.5--3.5 mm. Capsule narrowly ovoid, 1--1.8 cm. Seeds 1.1--1.4 mm; wings 8--10. Fl. Jul--Aug, fr. Sep--Oct.

Pools, rice fields, banks of lakes. Anhui, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Jilin, Liaoning, Nei Mongol, Shaanxi, Shandong, Shanxi [Indonesia, Japan, Korea, Pakistan, Russia (Siberia), Vietnam].

The entire plant is frequently used as feed for poultry and livestock.