Hydrilla HYDROCHARITACEAE GRAMINEAE Ottelia 



of the world. (Greek: hydr, water, and "rill"; referring to the habitat.) 



1. Hydrilla verticillata (L.f.) Royle MM (Hei Tsao; Black Pondweed) (H.F. 5: 659). 

 Submersed herb; fls. greenish white, VI-VIII; fr. VII-IX. Eurasia, Australia; 

 locally in An., Che., Hup., Ki., Ku. Streams, ponds, and lakes. Fig. 398. 



2. Vallisneria Linn. Tape Grass t^j^M (K'u Ts'ao Shu) 



Dioecious submersed tufted stemless herbs with long thin linear Ivs. : staminate 

 fls. numerous, borne in ovoid heads on short pedicels which break allowing the mature 

 fl. heads to escape and float on the water surface where their pollen is shed : pistillate 

 fls. solitary on long scapes which lengthen so that at maturity the fls. float on the 

 surface of the water where pollination takes place, but later coil up spirally, pulling 

 the ovaries under water where the frs. mature; perianth segments 3; stamens usually 

 3: fr. berry-like. 3-4 species, in all warm regions; one in China. (In honor of A. 

 Vallisneri, an early Italian botanist.) 



1. Vallisneria spiralis Linn. Eel Grass ^^ (K'u Ts'ao; Bitter Grass) (G.M. 94). 

 Submersed herb; fls. IX; fr. X. Eurasia, Australia, North America; locally in 

 An., Ku. Canals and deep streams. Fig. 399. 



3. Hj'drocharis Linn. 7^11 (Shui Pieh Shu; Water Turtle Genus) 



Dioecious floating herbs with creeping rootstocks, long-petiolate orbicular-cordate 

 Ivs. and white fls.: staminate fls.: 2-3 together: pistillate fls. solitary; stigmas 

 solitary: testa of the seed pulpy, filled with spiral vessels. 2 species, one in China. 

 (Greek: hydro, water, and chairein, to rejoice.) 



1. Hjdrocharis dubia (Bl.) Backer (H. morsus-ranae Linn. var. asiatica (Miq.) Mak.; 

 H. asiatica Miq.) Asiatic Frog's Bit n#i (Pai P'in; White Marsilea) (Mak. F. 

 884). Floating herb; fls. white, VII-IX; Ivs. with a thickened spongy pad in the 

 center. Asia, East Indies; locally in An., Che., Ku. Ponds and lakes. Fig. 400. 



4. Ottelia Pers. 7JC^fiiM (Shui Ch'e Ch'ien Shu) 

 Stemless submerged herbs with narrow crowded Ivs., some long-petioled and float- 

 ting, with broad {lanceolate or ovate) blades: fls. bluish, solitary, perfect, on a tubular 

 2-fid spathe; petals large, obovate or orbicular, with fleshy appendages at the base; 

 stamens 6-15: ovary oblong, beaked, almost 6-celled, 6-valved in fr.: seeds many, 

 with pulpy testa. 6-7 species: tropical and subtropical; one in China. 



1. Ottelia alismoides Pers. zfcMj (Shui Ch'e Ch'ien; Water-Plantain) (H.F. 5: 662;. 

 Aquatic herb; fls. lavender-purple, IX; fr. X. Asia, East Indies, Australia; locally 

 in An., Hup., Ki., Ku. Canals, deep streams. Fig. 401. 



178. GRAMINEAE Grass Family ^t~Pl (Ho Pen K'o; Cereals Family) 



Herbs or woody plants with hollow or sometimes solid stems (culms) and 2-ranked 

 (distichous) usually parallel- veined Ivs. consisting of a usually flat sessile blade and a 

 sheath which encloses the culm and has overlapping margins, with a membranous 

 hyaline or hairy appendage (ligule) on the inside at the junction of blade and sheath: 

 inflorescence of spikelets arranged in spikes, spikelike racemes or panicles, usually 

 terminal: spikelet consisting of one or more flowers (florets), variously modified, 



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