Order 150.— PONTEDBRIACE^E. 721 



to 12, hypogynous, longer than the sepals; anthers introrse ; styles 3 ; 

 capsule 3-partible, co-seeded. — 21 Herb glabrous, with a slender, rush- 

 like stem, dry, rush-like lvs., and a raceme of 6 to 9 yellow lis. 

 P. tenuifolia Rich. Bogs, N. Car. (Curtis), S. Car. (Michx.) St. 1 to 2f high, 



from red, fibrous roots. Lvs. perennial-green, very narrow, sheathing at base, 



nearly If long. Caps, brown. 



Order CL. PONTEDEPJACEJE. Pontederiads. 



Plants aquatic, with the leaves parallel- veined, mostly dilated at base. Fls. spath- 

 aceous. Perianth tubular, colored, 6-parted, often irregular and circinate after 

 flowering. Stamens 3 or G, unequal, perigynous. Ovary free, 3-cellcd. Style 1. 

 Stigma simple. Capsule 3 (sometimes l)-celled, 3-valved, with loculieidal dehis- 

 cence. Seeds numerous (sometimes solitary), attached to a central axis. Albumen 

 farinaceous. 



Genera 6, species 30, found exclusively in America, E. Indies, and tropical Africa. They an 

 of no known use. 



* GENERA. 



Flowers irregular, blue. Stamens 6. Utricle 1 -seeded Pohtedebia. 1 



Flowers regular. — Anthers 3, of 2 forms. Leaves reniform IIeteuantiieba. 9 



— Anthers 3, of one form. Leaves linear Sciioixicka. S 



1. PONTEDE'RIA, L. Pickerel Weed. (In honor of Julius Pen- 

 tedcra, a botanic author and professor, of Padua, about 1720.) Perianth 

 bilabiate, tubular at base, under side of the tube split with 3 longitudi- 

 nal clefts (the 2 lower sepals free), circinate after flowering and persis- 

 tent ; stamens unequally inserted, 3 near the base and 3 at the summit 

 ot the tube; utricle 1-seeded (2 cells abortive). — Lvs. radical, long- 

 petioled. St. 1-leaved, bearing a spike of blue fls. 



1 P. cordata L. Lvs. cordate-oblong, obtuse ; petiole shorter than the peduncle ; 

 spike cylindrical, pubescent. — H Can. and U. S. A fine, conspicuous plant, na- 

 tive of the borders of muddy lakes, &c, growing in patches extending from tha 

 shores to deep water. Stem thick, round, erect, arising 1 — 2f above the water, 

 bearing a single leaf. Leaves 4 — 7' by 1^ — 3', very smooth and glossy, almost 

 sagittate, with veins beautifully arranged to conform to the margin. Flowers in 

 a spike, arising above the spathe, very irregular. Perianth 2-lipped, each lip 3- 

 cleft, always blue, appearing in July. 



p. axgustifolia Torr. Lvs. narrow, truncate and subcordate at base. 



2 P. lancifolia Muhl. Lvs. lance-oblong or lance-linear, rather acute at each end; 

 petiole shorter than the peduncle ; spike cylindrical, pubescent. — Fools and 

 ditches, Ga. (Feay) and S. Car. More slender every way than the other, 15 to 30* 

 high. We can detect no difference in its flowers, but the permanent difference 

 of the leaves is worthy of consideration. Apr., May. 



2. HETERANTHERA, Ruiz & Paw (Gr. irtpa, otherwise, dvdf}pd\ 



the anthers being dissimilar in the same flower.) Spathe several- 

 flowered; tube of the perianth long and slender, limb 6-parted, equal ; 

 stamens 3 ; anthers of 2 forms, the lower oblong-sagittate, on a longer 

 filament; capsule 3-celled, many-seeded. Lvs. mostly reniform, long- 

 petioled. 



H. reniformis R. & P. St. prostrate or floating; lvs. suborbicular, reniform or 

 auriculate at base ; spathe acuminate, few-flowered. — On muddy or inundated 

 banks, Mid and W. States. Stem 4' to a foot or more in length. Leaves %' by 

 'f, on petioles 1 — 2' long, with a broad sinus at base, and a short, abrupt acumi- 

 nation. Spathe closely enveloping the 2 or 3 very evanescent, white flowera 

 Tube of the perianth £' long, limb "in 6 oblong segments. Filaments inserted at 



46 



