ALISMACE^. (water-PL ANTAIN FAMILY.) 491 



shaped. Leaves or some of them commonly furnished with a blade. 

 (Flowers perfect, monoecious, or sometimes dioecious.) 



3. Allsma. riowers perfect, with definite, mostly 6 stamens. Carpels flattened, whorled. 



4. Kvliinodorus. Flowers perfect, with 6 - many stamens. Carpels capitate, ribbed. 



5. Sagittarla. Flowers monoecious, rarely dioecious, with indefinite, rarely few stamens. 



Carpels capitate, flattened, winged. 



1. TBIGLOCHIN, L. Arrow-gkass. 



Sepals and petals nearly alike (greenish), ovate, concave, deciduous. Sta- 

 mens 6 : anthers oval, on very short filaments. Pistils united into a 3 - 6-ceUed 

 compound ovary : stigmas sessile : ovules solitary. Pod splitting when ripe 

 into 3-6 carpels, which separate from a persistent central axis. — Perennials, 

 with rush-like, fleshy leaves, below sheathing the base of the wand-like naked 

 and jointless scape. Flowers small, in a spiked raceme, bractless. (Name 

 composed of rpeir, thr^e, and yXaxiv, point, from the three points of the ripe 

 fruit in No. 1 when dehiscent.) 



1. T. pall!lStr6, L. Scape (6'-18' high) and leaves slender ; fruit linear- 

 club-shaped ; the 3 carpels when ripe separating from below upwards leaving a 

 triangular axis, awl-pointed at the base. — Marshes, both fresh and brackish, New 

 York to Illinois, and northward. Aug. (Eu.) 



2. T. maritimum, L. Scape (12' -20' high) and leaves thichish, fleshy, 

 fruit ovate or oblong, acutish, of 6 or rareli) 5 carpels which are rounded at the base 

 and sliyhtly grooved on the back; the edges acute. — Salt marshes along the coast, 

 also salt springs in the interior, shore of the Great Lakes, and northward. — 

 Var. elXtcm (T. elatum, Nuit.) grows in cold and fresh bogs, from W. New 

 York to Wisconsin, often 2j° high, and has the angles of the carpels sharper, 

 or almost winged. (Eu.) 



2. SCHEUCHZERIA, L. Scheuchzeria. 



Sepals and petals oblong, spreading, nearly alike (greenish-yellow), but the 

 latter narrower, persistent. Stamens 6 : anthers linear. Ovaries 3, globular, 

 slightly united at the base, 2-3-ovuled, bearing flat sessile stigmas, in fruit 

 forming 3 diverging and inflated 1 - 2-seeded pods, opening along the inside. — 

 A low bog-herb, with a creeping jointed rootstock, tapering into the ascending 

 simple stem, which is zigzag, partly sheathed by the bases of the grass-like con- 

 duplicate leaves, and terminated by a loose raceme of a few flowers, with sheath- 

 ing bracts. (Named for John and John Jacob Scheuchzer, distinguished Swiss 

 botanists early in the 18th century.) 



1. S. pallistris, L. — Peat-bogs, New England to Pennsylvania, Illinois, 

 and northward. July. (Eu.) 



3. AIjISMA, L. Water-Plantain. 



Elowers perfect. Petals involute in the bud. Stamens definite, mostly 6. 

 Ovaries many in a simple circle on a flattened receptacle, forming flattened cori- 

 aceous achenia, which are dilated and 2-3-keeled on the back. — Roots fibrous. 



