Triglochin UJNCAGINACFAF-ALISMACEAE Sagittaria 



1. Triglochin Linn. Arrow-grass HHHM (San Nang Tsao Shu) 

 Tufted perennial marsh herbs with basal distichous sheathing lvs. ; blade half-round 

 or terete: fig. scapes exceeding the lvs.: fls. in bractless spikes or racemes; perianth 

 segments concave, deciduous; stamens with very short filaments: carpels 1-seeded, 

 separating at maturity from the persistent central axis. About 14 species, in temperate 

 and subarctic regions; 2 in China. (Greek: treis, three, and glochis, points; from the 

 three points of the mature fruit in T. palustris.) 



Key to the Species 



Carpels 6 (sometimes 3), oblong or ovoid, with recurving beaks 1 . T. maritima 



Carpels 3, linear or clavate, separating from below upward 2. T. 'palustris 



1. Triglochin maritima Linn. Seaside Arrow-grass (G.M. 83). Scapose perennial, 

 12-20 cm. high; fls. greenish white, V-VI; fr. VIII-IX. Temperate and subarctic 

 regions; locally in Ku. Saline or fresh marshes. 



2. Triglochin palustris Linn. Marsh Arrow-grass (G.M. 83). Scapose perennial, 30- 

 45cm. high; fls. VI; fr. VIII. Temperate and subarctic regions; locally in An., 

 Ku. Brackish or calcareous places. 



175. ALISMACEAE Water Plantain Family if j|jf4 (Tse Hsieh K'o) 



Marsh herbs with erect scapose stems, mostly basal sheathing lvs. and perfect or 

 unisexual petalous fls.; sepals and petals 3; stamens usually 6 or more: ovaries 6 or 

 more, apocarpous, becoming achenes in fr. 14 genera with 60 species, in warm and 

 temperate regions; 3 genera and 3 or more species in China. 



Key to the Genera 



Fls. bisexual : If. blades lanceolate to ovate 1 • Alisma 



Fls. unisexual: If. blades usually arrow-shaped (oursj 2. Sagittaria 



1. Alisma Linn. Water Plantain Mj'MM (Tse Hsieh Shu) 

 Lf. blades lanceolate to ovate: fls. perfect, smaller than in Sagittaria; sepals and 

 petals 3; stamens usually 6: carpels arranged in a circle on a flattened receptacle, 

 forming flat coriaceous achenes. About 10 species, cosmopolitan; one or more in 

 China. (The Greek name.) 



1. Alisma canal iculatum A. Br. & Bouche ex Sam. WiM (Tse Hsieh; Water Purge) 

 (Ark. Bot. 24A (7): 29). Erect perennial, to 0.7 m.; fls. white, VII; fr. IX; lvs. 

 linear-lanceolate. China, Korea, Japan; locally in An., Che., Ki., Ku. Pond 

 margins, ditches. 



2. Sagittaria Linn. Arrowhead &$fM (Tz'u Ku Shu) 

 Perennial stoloniferous herbs with latex: early lvs. without blades; the later ones 

 with arrow-shaped (ours), lanceolate or ovate blades: fls. unisexual, in whorls of 3, 

 with membranous bracts; stamens usually numerous: ovaries many, forming flat 

 membranous winged achenes. 30 species, in temperate and tropical regions; one or 

 more in China. (Latin: sagitta, an arrow, referring to the shape of the leaves.) 



Key to the Species 



Lvs. reduced to flattened phyllodes, linear-oblong; no evidence 



of sagittate blades : plant 8-15 cm. tall 1 . S. pygmaea 



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