1118 BENGAL PLANTS. [Alisma. 
Order CXLYII. ALISMACEA. 
uatic or marsh herbs; usually erect, sometimes floating. 
Leaves radica clustered at nodes of floating stems, entire, 
soiled, often seca dotted or -lineolate. Flowers pedicelled, 
hermaphrodite, monccious, or polygamous, rarely diccious, in 
mbelled or paniculate whorls, white or pink, rarely blue or 
yellow ; eee . or more, membranous;  bracteoles small. 
Perianth 2-se ; the outer whorl of 3 herbaceous, the inner 
whorl petaloid, posi obsolete. Stamens 6 or more, rarely 3, hypo 
gynous or perigynous; anthers erect, basifixed, 2-celled; dehis- 
cence by lateral or dorsal longitudinal slits. arpels 3-6, or 
ipitate on a 
ait long or short, rarely 0, subterminal or ventral; stigma 
imple ; ovules 1 or more in each carpel; placentas on the inner 
nS rarely ovule solitary and basilar. Frwit of small achenes 
or follicles, the ripe carpels free or connate at the base only, 
usually tipped by the athe and aide very rarely each carpel 
circumscissile at the base. Seeds small or minute; albumen 0; 
embryo straight or ec Se 
Fruit indehiscent, of 3 or more achenes; ovules and seeds solitary :— 
Stamen: ; receptacle flat 
? ’ 
Flowers hermaphrodite Alisma. 
Flowers polygamous Li hyton. 
mens usually many, rarely as few as 6; receptacle globose or 
oblong; flowers 1-sexual or polygamous ........0...sseeeeeeeees gittaria. 
Fruit dehiscent, of 6-7 follicles ; stamens 8-12; flowers hermaphrodite ; 
ovules and seeds numerous Butomopsis. 
1015. Alisma Linn. 
Herbs, scapigerous, stemless, palustrine, perennial ; leaves lan- 
P 
flat. Sepals 3, ETN persistent. Petals 3, membranous, 
deciduous. Stamens 2-3-seriate, 6 or 9; filaments filiform. Car- 
pels few or en receptacle small; stigma small, terminal ; 
ovule solitary, anatropous, basilar. Frwit of few or many, com- 
pressed or turgid, coriaceous or hard achenes. Seeds erect, 
basilar ; testa membranous; embryo horseshoe-shaped. 
