Lemna 



LEMNACEAE-ERIOCAULACEAE Eriocaulon 



1. Lemna minor Linn. ^K (Fu P'iao; Floating-drifting duckweed) (G.M.386). Foot- 

 ing; fr. VI-IX. Temperate and tropical regions; locally in Che., Ki., Ku. On 

 ponds and lakes. Fig. 468. 



2. Lemna paucicostata Hegelm. (M.F.134). Floating; fr. VI-IX. Tropical regions; 

 locally in Hon., Ku. On ponds and lakes. 



3. Lemna trisulca Linn. &$ (P'in Tsao) (G.M.386). Floating. Temperate and tro- 

 pical regions; locally in Ku. On ponds and lakes. 



3. Wolffia Horkel ex Schleid. MWM (Wu P'ing Shu) 

 Thallus minute, nerveless, rootless: fls. bursting through the upper surface, two 

 in one place; one staminate and one pistillate. 12 species, in tropical and temperate 

 regions; one in China. The simplest and smallest of fig. plants. (Named for Johann 

 Friedrich Wolff, who wrote on Lemna in 1801.) 



1. Wolffia arrhiza (L.) Wimm. (Hegi 2:142). Floating; thallus minute, rootless. 

 World wide; locally in Ku. On ponds and lakes. 



183. ERIOCAULACEAE Pipewort Family Wfc&'ft ( Ku Ching Ts'ao K'o) 

 Aquatic or marsh herbs, usually stemless, and with lvs. crowded in a rosette: 

 infl. in pedunculate globular or hemispherical androgynous pubescent involucrate heads: 

 perianth of scales, often of two whorls: fr. a 3-lobed membranous capsule with small 

 seeds. 12 genera with 1,100 species, in warm countries; one genus and 20 species in 

 China. 



1. Eriocaulon Linn. Pipewort iMf^JR (Ku Ching Ts'ao Shu) 

 Fls. androgynous and monoecious, both kinds in one head: perianth double, of two 

 whorls; stamens 2xthe lobes of the inner perianth whorl; anthers 2-celled. Over 250 

 species, in warm countries; 20 in China. (Greek: erion, wool, and caulos, a stalk, 

 from the wool at the base of the scape in the original species.) 



Key to the Species 



Lvs. lanceolate, broad at the base, tapering to a fine point, 3-5 mm. 

 broad at middle: anthers black. 



Floral bracts glabrous 1. E. alpestre 



var. robustius 

 Floral bracts with white opaque (when dry) hairs at tip on back 2. E. buergerianum 

 Lvs. linear, narrow at base, about 1mm. broad at middle: anthers 



white 3. E. sieboldianum 



1. Eriocaulon alpestre Hk.f. & Thorns, var. robustius Maxim. (E. robustius (Maxim.) 

 Mak.) (Mak.F.772). Tufted herb, 10-25 cm. high; fls. straw-colored, IX. Eastern 

 Asia; locally in Che., Ku. Stream banks. 



2. Eriocaulon buergerianum Koern. (E.P.IV.30:94). Erect, 15-25 cm. high; fls. 

 white, VIII. Eastern Asia; locally in An., Ki., Ku. Swamps and slow streams. 

 Fig. 469. 



3. Eriocaulon sieboldianum Sieb. & Zucc. &$?:$: (Ku Ching Ts'ao; Essence-of- 

 cereal Herb) (Mak. F. 771). Erect, 5-15 cm. high; fls. straw-colored, IX-X; anthers 

 white. Eastern Asia; locally in An., Che., Ki. In shallow water. 



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