266 PONTEDERIACEAE (PICKEREL-WEED FAMILY) 



shaped, branching, pendulous ; leaves thread-shaped ; peduncle short, 1-flow- 

 ered ; flower yellow. E. Va., s. to Fla., and westw. ; growing on the branches 

 of trees, forming long hanging tufts. 



PONTEDERIACEAE (PICKEREL-WEED FAMILY) 



Aquatic herbs, with perfect more or less irregular flowers from a spalhe ; the 

 petal-like 6-merous perianth free from the 3-celled ovary; the 3 or 6 mostly 

 unequal or dissimilar stamens inserted in its throat. Perianth with the (> 

 divisions colored alike, imbricated in 2 rows in the bud, the whole together 

 sometimes revolute-coiled after flowering, then withering away, or the base 

 thickened-persistent and inclosing the fruit. Anthers introrse. Ovules anat- 

 ropous. Style 1 ; stigma 3-lobed or 6-toothed. Fruit a perfectly or incompletely 

 3-celled many-seeded capsule or a 1-celled 1-seeded utricle. Embryo slender, 

 in floury albumen. 



1. Pontederia. Spike many-flowered. Perianth 2-lipped, its fleshy persistent base inclosing 



the 1-seeded utricle. Stamens 6. 



2. Heteranthera. Spathe 1-few-flowered. Perianth salver-shaped. Stamens 3. Capsule 



many-seeded. 



1. PONTEDERIA L. PICKEREL-WEED 



Perianth funnel-form, 2-lipped ; the 3 upper divisions united to form the 3- 

 lobed upper lip ; the 3 lower spreading, and their claws, which form the lower 

 part of the curving tube, more or less separate or separable to the base ; tube 

 after flowering revolute-coiled. Stamens 6 ; the 3 anterior long-exserted ; the 

 3 posterior (often sterile or imperfect) with very short filaments, unequally 

 inserted lower down ; anthers versatile, oval, blue. Ovary 3-celled ; two of the 

 cells empty, the other with a single suspended ovule. Utricle 1-celled. Stout 

 herbs, with thick creeping rootstocks, producing erect long-petioled leaves, and 

 a 1-leaved stem, bearing a spike of violet-blue ephemeral flowers. Root-leaves 

 with a sheathing stipule within the petiole. (Dedicated to Pontedera, Professor 

 at Padua in the 18th century.) 



1. P. cordata L. Leaves heart-shaped, blunt ; spike dense, from a spathe- 

 like bract ; upper lobe of perianth marked with a pair of yellow spots (rarely 

 all white); calyx-tube in fruit crested with 6-toothed ridges. N. S. to Out.. 

 Minn., and Tex. July-Sept. (Trop. Am.) Var. ANGUSTII^LIA Torr. Leaves 

 lanceolate or triangular-attenuate, roundish or truncate at base. Same range. 



2. HETERANTHERA R. & P. MUD PLANTAIN 



Perianth with a slender tube ; the limb somewhat equally 6-parted, ephemeral. 

 Stamens in the throat, usually unequal ; anthers erect. Capsule 1-celled or 

 incompletely 3-celled by intrusion of the placentae. Low herbs, in mud or 

 shallow water, with a 1-few-flowered spathe bursting from the sheathing side 

 or base of a petiole. (Name from rfya, different, and &v$T)p<i, anther.) 

 * Stamens unequal; 2 posterior filaments with ovate yellow anthers; the other 

 longer, with a larger oblong or sagittate greenish anther; capsule incom- 

 pletely 3-celled ; leaves rounded, long-petioled; creeping or floating plants. 



1. H. renif6rmis H. & P. Leaves round-kidney-shaped to cordate and acute ; 

 spathe 3-5-flowered; flowers white or pale blue. Ct. to Neb., and southw. 

 (S. A.) 



2. H. Iim6sa (Sw.) Willd. Leaves oblong or lance-oblong, obtuse at both 

 ends; spathe 1 -flowered ; flowers larger, blue. Va. to Neb., and southw. 

 (S. A.) 



