ALTSMACEiE. 505 



MONOCOTYLEDONES. 



CXXV. ALISMACEiE. 



Flower-organs distinct from each other, or the carpids connected below. Seeds cxalbu- 

 minous: embryo mostly curved, with a large, usually slender radicle. — Aquatic or bog- 

 planta ; leaves rosular, mostly furnished with a blade ; pedicels umbellate or whorled. 



1. ECHINODORUS, Rich. 



Flowers hermaphrodite or polygamous. Sepals 3. Petals 3, imbricativc. Stamens 

 usually definite, 6 or more. Achenia 1-seeded, pluriserial ou a convex torus, longitudinally 

 ribbed or crested. 



1. E. cordifolius, Gr. Scape erect, 5-3-angular, paniculate, with distant, herma- 

 phrodite whorls and umbels ; leaves emerging, cordate-roundish, 9-5-nerved, shorter than 

 the long petiole ; sepals many-ribbed, little shorter than the white petals; stamens 12-15 ; 

 ovaries numerous, shorter than the style; carpids beaked : ribs about 12, entire. — Plum. 

 Ed. Burm. t. 231. /. 2. — Alisma, L. A. Berteroaum, Balb. A. Sprengelii, Kth. r young 

 specimens with oval or oblong, prinioidal leaves. — 2'-4'high; leaves 5 "-3", petals 2 £"' long, 

 earpid-heads 3'" diam. : beak at length half as long as the carpid. — Hab. Jamaica !, Bancr., 

 March, in shallow ponds ; Antigua !, Wullschl. ; [French islauds ! ; Guiaua !, Brazil !]. 



2. E. guianensis, Gr. Scape simple, submersed, terminated by few-flowered umbels 

 or whorls ; leaves floating, hastate-oca!, with the auricles somewhat pointed, much shorter 

 than the submersed petiole ; petals white, yellow at the base, little exceeding the many- 

 ribbed sepals; stamens 6-12: styles shorter than the ovaries ; carpids beakless : muricate 

 crests about 8, the dorsal larger. — Mart. Fl. Bras. 8. t. 13./". 3 ; t. 15. f 1. — Sagittaria, 

 Kth. S. echiuocarpa, Mart. (Alisma, Seub.). S. Senbertiana, Mart. : a form with rounded 

 leaf-auricles. — Leaves 2" long, smaller in a low, terrestrial form ; petals 6"'-9'" long, earpid- 

 heads 5'" diam. — Hab. Trinidad!, Cr., in savannahs; [Mexico to Brazil!]. 



2. SAGITTARIA, L. 



Character of Echinodorus, but ilowers uuisexual, stamens usually indefinite, and achenia 

 flat, winged. —Emerging water-plants; primordial leaves devoid of a blade: in the sub- 

 sequent ones the blade is developed often by degrees ; flowers white, usually monoecious, 

 the superior 3 . 



3. S. acutifolia, L. Leaves sagittate, with the inferior veins recurved, (passing by 

 oval-oblong blades into the primordial ones) ; whorls distant : pedicels subequal ; stamens 

 numerous : filaments longer than the anthers ; carpids shortly mucronate, wholly sur- 

 rounded by a wing. — Desc. Fl. 7. t. 497. — Distinguished from the allied S. sagiftifolia, L. 

 of the Old World by the fruit, and by longer filaments, and from S. obtusa, W. of the United 

 States by the nearly beakless carpids. — Hab. Jamaica!, all coll., in ditches; [Guiana!]. 



4. S. lancifolia, L. Leaves oval, tapering at the base, other oval-oblong or elliptical- 

 lanceolate : all veins ascending; whorls few-flowered, distant: superior pedicels shorter; 

 stamens numerous : anthers lotiger than the filaments ; carpids mucronate . wing dorsal, 

 spongious. — Bot. Mag. t. 1792. Red. Lit. t. 411. Desc. Fl. 1. t. 498.— S. angustifolia, 

 Lindl. S. ovata, Red. : the form with the leaves quite developed. — Stouter than the pre- 

 ceding ; flowers large, but petals variable in size. — Hab. Jamaica !, Wilt., Pd., M'Nab, in 

 ditches and lagoons ; [Cuba to Guiana !]. 



