杜若

Perennial stout herbs, scabrous, 40-110 cm tall. Roots fibrous. Leaves sessile to subpetiolate; blade reduced towards inflorescence, lanceolate-elliptic, 13-27 cm long, 2.8-5.6 cm wide, apex acuminate, base cuneate, densely scabrescent and sparsely uncinate above, uncinate and strigose beneath, the midrib impressed above, raised beneath; sheaths cylindrical, overlapping, sparsely uncinate. Inflorescence a terminal thyrse; peduncle densely covered with long uncinate hairs; bracts lanceolate, 4.5-6.5 mm long, 2-3 mm wide, uncinate; bracteoles deltoid, infundibuliform, perfoliate, ca. 2 mm long, ca. 1.5 mm wide, glabrous; pedicel ca. 3.5 mm long, glabrous. Flowers actinomorphic, dimorphic: in functionally male flowers pistil abortive, ca. 2 mm long; in bisexual flowers the pistil ca. 7 mm long; sepals 3, free, white, persistent, elliptic, concave, 2.9-4 mm long, 2.1-3.5 mm wide, apex obtuse, glabrous; petals 3, white, equal, oblanceolate, 3.7-5.5 mm long, 2-2.8 mm wide, apex acute, base cuneate; stamens 6, fertile, subequal; the anticous 3, anthers yellow, elliptic, 1 mm long; filaments ca. 4.5-6 mm long; the posticous 3, anthers yellow, elliptic or irregular, ca. 0.4-0.6 mm long; filaments 3-4 mm long; ovary globose-ellipsoid, ca. 2 mm long; style ca. 5 mm long. Capsules indehiscent, trilocular, indigo, metallic, globoid, diam. ca. 5 mm, locules 8-seeded,. Seeds biseriate, polygonal, dorsiventral, 2-2.7 mm long, 1.2-1.75 mm wide, ca. 1.25 mm thick, scrobiculate, embryotega dorsal, deeply sunken, hilum punctiform. Chromosome number: n = 16.

Taiwan: Formosa, Faurie 8390 (TAI). Taipei: Sanhsia Town: Lelekuo, Shih s. n. 1988 (TAIF, HAST); same loc., Y. J. Chen & Wang 860 (TNU); same loc., Chen 2099 (TNU); Sanhsia, elev. ca. 400 m, Wang 3299 (TAI); Sanhsia: Wuliaochien, elev. ca. 450 m, Peng 8709 (HAST); Sankyo, Shimada s. n. Sep. 24, 1913 (TAIF). Taoyuan: Fusing, Yang 2673 (TAI); Fuhsing District: en route from Hsiayun to Hsiayunping. Along roadside and roadside slopes, elev. ca. 300-360 m, Peng 10278 (HAST); Kappanzan, Maw 1115 (TAI); same loc., Suzuki 4608 (TAI); Kuanhsi to Fusing, elev. ca. 500 m, Huang 4819 (TAI); Fuhsing District: en route from Paling to Kaoyi, elev. ca. 500-600 m, Peng 11040 (HAST); Paling. Chen 34 (TNU); Paling check point, Y. J. Chen et al. 526 (TNU); en trail from lower Paling to upper Paling, Y. J. Chen et al. 642 (TNU); Tahsi Town, Y. J. Chen 842 (TNU). Hsinchu: Wufeng Hsiang: On the way from Shihlu to Chingchuan. Secondary broadleaf forest with intermixed bamboo and Cunninghamia plantations, elev. ca. 1000-1455 m, Wang & Liu 72 (HAST). Miaoli: Nanchuang, Hsu & Kao s. n. Aug. 3, 1960 (TAI); Malabangshan, elev. ca. 825-1000 m, Huang et al. 15631 (TAI); Szumahsien logging trail, Y. J. Chen 841 (TNU); Santou spring, Huang 1064 (TAI); Shihtan Hsiang: Shihtan, Margin of orange orchard, elev. ca. 250 m, Leu & Lin 1056 (HAST); Taian Hot-spring, elev. ca. 300-400 m, Wang et al. 7675 (TNU). Taichung: en route from Chunghsing Ling to Takeng (via Toukeshan Mt. ridge). On subridge of mountain, elev. ca. 650 m, Peng 9982 (HAST); Takeng mountain hiking trail. Secondary broadleaf forest, elev. ca. 445 m, Wang et al. 284 (HAST); same loc., elev. ca. 625-695 m, Wang et al. 248 (HAST); Lishan, Kuoh s. n. Aug. 5, 1969 (TAI). Nantou: Baibara Hori, Suzuki s. n. Jul. 20, 1926 (TAI); Gettan, Kudo & Sasaki s. n. Sep. 20, 1929 (TAI); Hsinyi District: Hoshe Expt'al Forest, elev. ca. 800-900 m, Peng & Chen 10992 (HAST); Huasenlinchung, Kuoh 4168 (TAI); same loc., Y. J. Chen & Hsu 745 (TNU); Jenai Hsiang: Hui-Sun Experimental Forest. Along the trail to Chingwashih; in secondary broadleaved forest, elev. ca. 600-700 m, Wu et al. 10 (HAST, TNU); Hui-Sun Experimental forest, Camp. Area, Y. J. Chen & Hsu 757 (TNU); Kuantaochi, Chang 2221 (TAI); same loc.,. Chang 2140 (TAI); same loc., Moo 2258 (TAI); Jenai Hsiang: NCHU Hui-Sun Experimental Forest, along the trail to Chingwashih, Wu 10 (TAIF); Nenkao Forest Experiment Station, Huang et al. 6072 (TAI); Wushe, Sasaki s. n. Jul. 28, 1922 (TAIF). Kaohsiung: Maolin Hsiang: Shanping Station, Liukuei Branch, Taiwan Forestry Research Institute, elev. ca. 750 m, Wang & Lin 793 (HAST); Senping, Kuoh 4003 (TAI). Hualien: Taroko National Park: Yenhai Forest Trail, elev.ca. 650-700 m, Peng et al. 12413 (HAST); Toroko, Mori s. n. Jun. 1908 (TAIF).

Japan, Korea, China (Zhejiang, Fujian, Anhui, Jiangxi, Hubei, Hunan, Guangdong, Guangxl, Sichuan). Taiwan, in northern and central part, under forest in damp and semishady places from 300-1455 m. Flowering in May.-Nov., central in Jun.-Oct.

本分類群具有6枚可孕雄蕊，相對於雌蕊的3枚雄蕊略短，花藥有退化的現象，若花藥嚴重退化，其中的花粉則皺縮不可稔。由於花藥經常有退化的情形，使得鑑定上易和P. secundiflora混淆，然而P. secundiflora所有雄蕊皆明顯低於雌蕊 (長度約為雌蕊的2/3)，且可孕雄蕊和不可孕雄蕊花藥顏色不同，仔細觀察是可以區別的。

Phenology: perennial herbs, evergreen

Roors form: roots fibrous

Stems form: monomorphic stem

Monomorphic stems habit: rhizomatous

Rooting at nodes or not: rooting at nodes

Lateral shoots: perforating

Phyllotaxis: spiral phyllotaxis

Leaves: petiole: sessile, subpetiolate

Leaves: shape (if dimorphic leaves, selected by rosette leaves): lanceolate, elliptic

Leaves: apex: acuminate

Leaves: length (cm): 13-27

Leaves: width (cm): 2.8-5.6

Leaves indumentum: upper surface: pubscent

Prophyll: sheathing, apex acute

Inflorescence: take plance: terminal

Inflorescence: thyrse

Bracts: shape: lanceolate

Corolla: actinomorphic: petal 3, base free, equal or subequal

Flowers: bisexual, functionally male flowers

Sepals: sepal 3, equal

Sepals: color: white

Sepals: base: free

Sepals: shape: elliptic

Sepals: indumentum: glabrous

Sepals: length (if dimorphic sepals, selected by anticous two) (mm): 2.9-4

Sepals: width (if dimorphic sepals, selected by anticous two) (mm): 2.1-3.5

Flowers: color: white

Petals: shape: oblanceolate

Petals: length (mm): 3.7-5.5

Petals: width (mm): 2-2.8

Stamens form: monomorphic: fertile stamens 6

Ovarys: shape: globose-ellipsoid

Ovarys: indumentum: glabrous

Ovarys: length (mm): 2

Styles: indumentum: glabrous

Styles: length (mm): 5

Capsules: dehiscence: indehiscent

Capsules: shape: globoid

Capsules: trilocular

Capsules: indumentum: glabrous

Capsule locules seeds: number: 8

Capsules: length (mm): 5

Seeds: lengh (if dimorphic seeds, selected by dorsal one) (mm): 2-2.7

Seeds: width (if dimorphic seeds, selected by dorsal one) (mm): 1.2-1.75