1644 CXXXVI. PONTEDERIACEiE. 



1. *PONTEDERIA, Linn. 

 (After J. Pontedera.) 



Aquatic plants with stem-like or creeping rootstocks. Flowers nmnerous 

 usually crowded at the sides of a rhaehis, scarcely pedicellate, the inflorescence 

 terminal compound, and densely cylindrie, rarely almost simple and racemose. 

 Perianth funnel-shaped with an incurved slender, or rarely abbreviated tube. 

 Stamens 6. Eadical leaves on long petioles, the lamina cordate-ovate, rotundate 

 or rarely lanceolate, with a long loose sheath below the petiole. Stem or branch 

 erect, simple, 1 -leaved 



The species belong to N. and S. America. 



1. P. cordata (heart-shaped), Linn. Pickerel weed. Stems 1 to 2ft. high, 

 radical leaves few, lamina coriaceous, cordate-ovate, petioles dilated and sheathed 

 at the base. Flowers rather small in a more or less dense spike. Perianth blue 

 pubescent outside, the upper lobe with a greenish spot on the inside. — Bot. Mag. 

 1156; P. lanceolata, Lodd. Bot. Cab. 613. 



Hab.: An American aquatic naturalized in a few still waters near Brisbane. 



2. *EICHHORNIA, Kunth. 

 (After J. A. F. Eiehhorn.) 



Perianth funnel-shaped, tube short or elongated and slender, limb erecto- 

 patent, more or less oblique, the lobes not very unequal. Stamens 6, of unequal 

 length, declinate, some included, the others exserted, filaments filiform, slightly 

 flattened near the base. Ovary sessile, 3-celled. Style filiform ; stigma terminal 

 slightly dilated or very shortly 3 or 6 lobed. Ovules numerous in each cell. 

 Capsule enclosed in the withered perianth-tube, ovoid, oblong or linear ; pericarp 

 membranous. Seeds numerous, ovoid, many-ribbed, embryo cylindrie, albumen- 

 farinaceous. — Aquatic herbs with roundish, petiolate radical leaves, the petiole 

 often inflated. 



Natives of South America and tropical Africa. 



1. E. speciosa (showy), Kunth. Water Hyacinth. A floating plant, the 

 roots having a calyptrate covering at the extremity like Leimm. Stems very 

 short, the leaves almost entirely emersed, roundish but very variable in shape ? 

 petioles long or short, more or less inflated below the middle, with a sheathing 

 scale at the base. Scape from 6 to 12in. long, with several sheathing bracts. 

 Flowers 6 to 12, tube curved, glandular-pubescent outside near the base, pale- 

 purple ; the 5 lower-segments nearly equaJ, the upper one larger and marked 

 with a yellow spot in a cloud of blue. Stamens inserted within the tube 3 long 3- 

 short; filaments lilac with numerous pedicellate glands ; anthers oblong. Ovary 

 tapering upwards into the style, stigma capitate. — E. crassipes, Solms. ; E.. 

 crassicaulis, Schlecht. ; Pontedena azitrea, Sw. Bot. Mag. 2932, 

 Hab.: South America. Now naturalized in the still waters of southern localities. 



3. MONOCHORIA, Presl. 



(From monos, one, and chorizo, to separate ; the anterior stamen is different from' 



the remaining five.) 

 (Limnostaohys, P. v. M.) 

 Perianth nearly regular, divided to the base into 6 segments. Stamens 6, 1 

 usually larger or otherwise different from the others. Ovary 3-celled, with' 

 numerous ovules in each cell. — Leaves radical on long petioles. Scapes with a, 

 single apparently petiolate leaf, the short raceme in its axil appearing to proceed 

 from a swelling in the middle of the petiole. 



The genus contains very few species limited to the Old World ; the only Australian one, is 

 as far as known, endemic. 



