PONTEDERIACEAE 333 



ous. Stamens 3, dissimilar, the 2 upper ones short, with oval 

 yellow anthers, the other longer, with a larger oblong greenish 

 anther. Capsule oblong, somewhat trigonous, incompletely 3-celled, 

 several-seeded. Perennials : stem creeping ; leaves alternate, long- 

 petioled ; flowers white, or blue, in a slender few-flowered spike, 

 from a lateraj spathe. 



1. H. i < ii i 1 01 in is. R. $ P. Leaves roundish-reniform ; spathe 

 involute, acuminate, 3- to 5-flowered ; flowers white, fugacious. 

 REXIFORM HETERANTHERA. Mud Plantain. 



Stem 4 to 12 or 18 inches long, prostrate, radicating, branching from the base. 

 Leaves % of an inch to an inch and half in length, and wider than long, with 

 semicircular nerves ; petioles 1 to 2 or 3 inches in length. Spikes of flowers burst- 

 ing from the sheathing base, or side, of the petioles; perianth imperfectly ex- 

 panding. 

 Hob. Muddy margins of rivulets : frequent. Fl. July. Fr. Sept. 



454. SCHOULE V RA, Schreber. 

 [Dedicated to Frederick Adam Scholler, a German Botanist.] 

 Perianth salver-form, with 6 equal lance-linear lobes on a long and 

 very slender tube. Stamens 3, all similar and nearly equal (rarely 

 a fourth abortive one) ; anthers linear-oblong, sagittate. Style fili- 

 form. Capsule oblong, invested by the withered perianth, 1 -celled 

 with 3 projecting parietal placentae, several-seeded. Perennials: 

 stems submersed, swimming ; leaves narrow and grass-like, sessile ; 

 flowers yellow, floating, solitary, from subterminal axillary spathes. 



1. S. graillinea, Willd. Stems cespitose, slender, dichotomously 

 branching; leaves long, linear, translucent. 

 GRASS-LIKE SCHOLLERA. Water Star-grass. 



Stems 1 to 2 feet long, radicating at the lower nodes. Leaves 3 to 12 inches long, 

 membranaceous and somewhat sheathing at base. Spathe short, lanceolate. 

 Perianth-tube about an inch in length, slightly curved. 

 Hob. Slow-flowing waters; Brandy wine; Schuylkill: frequent. Fl. July. Fr. Sept. 



ORDER CXV. COMMELYNA N CEAE. 



Herbs; stems nodose, leafy, often branching; leaves alternate, sheathing at base; 

 flowers chiefly perfect, often irregular; perianth free from the ovary, consisting of 

 distinct calyx and corolla; sepals 3, persistent; petals 3, ephemeral, withering, 

 or deciduous; stamens 6, with introrse anthers, 2 or 3 of them sometimes modified 

 and abortive; style 1; stigma undivided; fruit a 2- or 3-celled loculicidal capsule, 

 3- or several-seeded ; embryo small, at the apex of densely fleshy albumen. 



455. COMMEI/rWA, Dillenius. 

 [Dedicated to John and Gaspard Commelyn ; early Dutch Botanists.] 



Flowers irregular : Sepals somewhat colored, unequal, the 2 lateral 

 ones partly united. Petals unequal, the 2 lateral ones rounded, 

 or reniform, on long claws, the other smaller and subsessile. 

 Stamens unequal, 3 or 4 of them abortive and smaller, with im- 

 perfect cross-shaped anthers; filaments naked. Capsule 3-celled, 

 2 of the cells 2-seeded, the other 1 -seeded, or abortive. Stems 

 branching, geniculate, often procumbent, and radicating at the 

 nodes ; leaves flattish ; flowers mostly blue, fascicled in the folded, 

 cordate, spathe-like bract, opening in succession, for a single 

 morning, and then shrivelling. 



