272 



Commelinaceae; Pontederiaceae; Philydraceae 



flower usually solitary, axillary, the peduncles 1.5-3 cm. long, 

 usually with a linear bract sometimes bearing an additional 

 flower in the axil, recurved in fruit; sepals lanceolate, acute; 

 petals pink, slightly longer than the calyx; stamens 3, the fila- 

 ments bearded at base; staminodes 3; capsule 10 mm. long, 



with several seeds in each locule.- Sept.-Oct. Common in 



wet places; Honshu, Shikoku, Kyushu. China, Ryukyus, 



and e. N. America. 



2. Aneilema nudiflorum R. Br. Commelina nudifiora 

 L., pro parte; Murdannia nudifiora (R. Br.) Brenan; A. mala- 



baricum sensu auct. Japon., non Merr. Shima-ibo-kusa. 



Perennial soft herb with rosulate radical leaves; leaves rather 



thick, lanceolate to narrowly so, 4-7 cm. long, 4-10 mm. wide, 

 acute, the sheaths 5-10 mm. long, coarsely pubescent in front 

 as on the margin of the blade; peduncles terminal and lateral, 

 ascending or decumbent, glabrous, 3-7 cm. long, sometimes 

 with a single bract; cymes densely several-flowered, one-sided, 

 glabrous, the pedicels slightly recurved, 3-4 mm. long; sepals 

 elliptic, rounded at apex, 3-4 mm. long; petals slightly longer 

 than the sepals, pale rose-purple; stamens 3, the filaments 

 bearded; staminodes 3; capsule ellipsoidal, slightly longer than 

 the sepals with 2 seeds in each locule, these about 1.2 mm. long. 



Aug.-Oct. Kyushu (Yakushima and Tanegashima) . 



Ryukyus, China, Philippines, Malaysia, and India. 



Fam. 



PONTEDERIACEAE Mizu-aoi Ka Pickerelweed Family 



Aquatic or marsh herbs with or without rhizomes; leaves radical and cauline, broad, parallel-nerved; flowers bisexual, ephem- 

 eral, in a spike arising from the sheath of the uppermost leaf; perianth-segments 6, in 2 whorls, free, similar, usually withering 

 away very early after anthesis; stamens 1-6, with basifixed or versatile anthers; ovary superior, 1- to 3-locular, with 3 parietal 

 placentae, the style slender, terminated by an entire or 3-fid stigma; ovules anatropous; capsule membranous, loculicidally dehiscent 

 into 3 valves; seeds small. About 5 genera, with about 40 species, chiefly in the Tropics. 



1. MONOCHOREA Presl Mizu-aoi Zoku 



Aquatic or growing in wet places; leaves all radical, except one on the apical part of the stem, long-petioled, the blade ovate, 

 lanceolate, linear, or sagittate; inflorescence a sessile or peduncled raceme, with a membranous sheath at the base of the pe- 

 duncle; perianth of 6, nearly free segments, campanulate, withering away early after flowering; stamens 6, similar, or the 

 central one of the inner series larger than the others, the filaments glabrous, with a tooth on one side at the base, the anthers 

 basifixed; ovary 3-locular, with numerous ovules.' Several species, chiefly in tlie Old World Tropics. 



lA. Stems 20-40 cm. long; leaves cordate; inflorescence many-flowered, long-peduncled, exceeding the uppermost leaf; flowers 2.5-3 cm. 



across 1 . M. \orsakpvn 



IB. Stems shorter; leaves broadly lanceolate to deltoid-ovate, sometimes shallowly cordate at base; inflorescence few-flowered, sessile or 



nearly so, much shorter than the uppermost leaf 2. A/, vaginalis var. plantaginea 



taginea (Roxb.) Solms-Laub. Pontederia plantaginea Roxb.; 



Monochoria plantaginea (Roxb.) Kunth ^Ko-nagi, Sasa- 



NAGi, Mizu-NAGi. Similar to the preceding species but 

 smaller; radical leaves long-petioled, the blade broadly lanceo- 

 late to deltoid-ovate, 3-7 cm. long, 1.5-3 cm. wide, rounded to 

 shallowly cordate at base, subabruptly narrowed to an acute or 

 obtuse apex, the cauline leaves on shorter petioles 3-10 cm. 

 long; inflorescence much shorter than the leaves, one-sided, 3- 

 to 7-flowered, abruptly deflexed at the base in fruit; flowers 

 purplish blue, 1.5-2 cm. across; perianth-segments oblong; cap- 

 sule ellipsoidal, about 10 mm. long; seeds ellipsoidal, about 1 



mm. long, longitudinally ribbed and transversely lineolate. 



Sept.-Oct. Common in paddy fields and shallow ponds in 



lowlands; Honshu, Shikoku, Kyushu. Korea and China. 



The typical phase occurs in se. Asia. 



1. Monochoria korsakovii Regel & Maack. M. vaginalis 



var. \orsa\ovii (Regel & Maack) Solms-Laub. Mizu-aoi. 



Glabrous, soft, somewhat fleshy annual; stems 20-40 cm. long; 

 radical leaves long-petioled, the blade cordate, reniform-cordate, 

 or rarely ovate-cordate, 5-10 cm. long and as wide, very ab- 

 ruptly attenuate to an obtuse apex, the cauline leaf similar, but 

 short-petioled; inflorescence terminal, rather many-flowered, 

 finally elongate and 5-15 cm. long in fruit; flowers on 

 obliquely ascending pedicels, 2.5-3 cm. across, purplish blue; 

 perianth-segments elliptic, about 15 mm. long; anthers versa- 

 tile, the larger one single, about 4 mm. long, light blue, the 

 others about 3 mm. long and yellowish; style curved; capsules 



narrowly ovoid-conical, about 10 mm. long. Sept.-Oct. 



Common in ponds and ditches; Hokkaido, Honshu, Shikoku, 

 Kyushu. Korea, Ussuri, and China. 



2. Monochoria vaginalis (Burm. f.) Presl var. plan- 



Fam. 49 PHILYDRACEAE Tanuki-ayame Ka Philydrum Family 



Erect perennials with 2-ranked, laterally flattened, linear leaves; inflorescence a spike or panicle; flowers small, subtended by 

 bracts, bisexual, zygomorphic; perianth-segments 4 in 2 series, persistent, petaloid; stamen solitary, arising from the base of the 

 anterior perianth-segment, with a flat filament and straight or twisted anther; ovary superior, 3- or l-locular with 3 parietal 

 placentae, the ovules anatropous, numerous; style terminal, with an entire stigma; capsule loculicidally dehiscent into 3 valves; 

 seeds numerous, minute. Three genera with few species, in Asia, Australia, and the Pacific Islands. 



1. PHILYDRUM Banks ex Gaertn. Tanuki-ayame Zoku 



Rather soft perennial herb; stamen not adnate to the perianth, with a twisted anther; ovary 1-locular.- 

 known. 



)nly one species 



