-206 CLi. LEMXACE^ (browx). [Wolffla, 



Jahrb. xxi. 302 ; Rendle in Cat. Afr. PL Welw. ii. 92. Telmatophace 

 cylindracea, Welw. ex Hegelmaier, Monogr. Lemn. 123. 



Itovrer Guinea. Angola : Libongo ; in rocky pools on the mountains behind 

 the Banza de Libongo, in the purest, freshest drinking-water, where no other plant 

 ^rows, Welwitsch, 212. 



Order CLII. ALISMACE^. (By C. H. Wright.) 



Flowers regular, hermaphrodite, moncecious or polygamous, very 

 rarely dioecious. Perianth-segments 6, 2-seriate or very rarely 1-seriate 

 by the absence of the inner whorl, imbricate ; outer usually herbaceous, 

 concave, nerved, persistent ; inner usually larger, petaloid, deciduous. 

 Stamens 6 or more, rarely 3, hypogynous or inserted on the base of the 

 perianth-segments ; filaments terete or flattened ; anthers basifixed, or 

 dorsifixed near the base, erect, obtuse, shortly bifid or with prolonged 

 connective, dehiscing by lateral or more or less dorsal longitudinal slits. 

 Carpels 6 to many, rarely 3, arranged in a verticil or spiral, distinct or 

 connate at the base, sessile or shortly stalked, 1 -celled; receptacle flat, 

 oblong or globose ; style subterminal or ventral, rarely absent ; stigma 

 terminal and small or slightly capitate, or ventral (rarely dorsal) and 

 decurrent ; ovules solitary or 2 superposed, attached to the inner angle 

 of the carpel, or numerous on reticulate parietal placentas. Fruit - 

 carpels distinct or connate at the base, 1 -celled, crustaceous, coriaceous 

 or membranous, usually bearing the remains of the style, indehiscent 

 or dehiscing by the ventral suture, very rarely circumscissile at the 

 base. Seeds small or minute, ovoid, oblong or compressed ; testa mem- 

 branous or coriaceous, smooth, rugose or slightly spiny ; albumen none ; 

 embryo horseshoe-shaped ; radicle thickened. — Aquatic or marsh herbs, 

 erect, rarely floating, usually glabrous, with milky juice, scapigerous or 

 caulescent, perennial, rarely annual. Rhizome short or long. Leaves 

 erect, rarely floating, radical or clustered at the nodes of a creeping 

 stem, petiolate ; lamina various, often pellucid-dotted or -striped ; 

 nerves converging towards the apex of the lamina. Inflorescence 

 indefinite, of racemose or spicate verticils, more rarely pseudo-umbellate 

 or with solitary flowers ; bracts at the base of the verticils or umbels, 

 membranous ; bracteoles small. Flowers white or rose, rarely yellow 

 or blue. 



Genera about 13, species about 60, in fresh water throughout the globe except in 

 the frigid zones. 



Tribe I. Alisxneae. — Oimle solitary and basal, or 2 {rarely more) attached 

 to the inner angle of the carpel. Carpels indehiscent. 

 ■-■^Inner perianth-segments petaloid, larger than the outer. 

 Carpels on a small receptacle. 



Flowers hermaphrodite . . . . .1. Alisma. 



Flowers polygamous ...... 2. Limkophtton. 



Carpels on a large oblong or globose receptacle. 



Flowers monoecious . . . . . .3. Lophotocaepus. 



Flowers hermaphrodite 4. Echinodoeits. 



Flowers dioecious ,,.... 5. Rautanexia. 



