80 ALISMACEAE (WATER-PLANTAIN FAMILY) 



1. Scheuchzeria. Ovaries 3, nearly distinct, at length divergent. Flowers bracteate, in a loose 



raceme upon a leafy stem. 



2. Triglochin. Ovaries 3-6, united until maturity. Leaves radical. Flowers braetless, in a 



spike-lil^e raceme terminating a jointless scape. 



1. scheuchz:6ria l. 



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

 latter narrower, persistent. Stamens 6 ; anthers linear. Ovaries S, globular, 

 slightly united at 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 conduplicate 

 leaves, and termimated by a loose raceme of a few flowers, with sheathing 

 bracts ; leaves tubular at the apex. (Named for Johann and Johann Jacob 

 Scheuchzer, distinguished Swiss botanists early in the 18th century.) 



1. S. paltistris L. — ^ Peat-bogs, and wet shores, e. Que. to N. J., westw. 

 across the continent. June. (Eurasia. ) 



2. THIGLdCHIN L. Akkow Grass 



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

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

 celled compound ovary ; stigmas sessile ; ovules solitary. Capsule 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. Plowers small, in a spiked raceme, braetless. 

 (Name composed of rpets, three, and yXaxiv, point, from the three points of the 

 ripe fruit in no. 3 when dehiscent.) 



Fruit thicker than long 1. T. atriafa. 



Fruit longer than thick. 



Fruit (with 3-6 carpels) ovoid-prismatic, about twice as long as thick . . 2. T. rtiaritima. 



Fruit (S-carpelled) clavate- or linear-prismatic, 8-5 times as long as thick . . 8. J*, palustris. 



1. T. striata R. & P. Scape (8-34 cm. high) and leaves slender ; flowers 

 very small ; sepals and stamens 3 ; fruit globose-triangular, or when dry 

 3-lobed. (T. triandra Michx.) — Salt marshes, near seashore, Md. to Fla. and 

 La. (S. A.) 



2. T. maritima L. Scape (1.5-7.5 dm. high) and leaves thiokish; fruit 

 ovoid or short-prismatic, acutish ; carpels 3- (more often) 6, rounded at base 

 and slightly grooved on the back, the edges acutish. — Salt marshes near the 

 coast. Lab. to N. J., and in saline, boggy, or wet places across the continent. 

 (Eurasia., n. Afr.) 



3. T. paMstris L. Scape (5-50 cm. high) and leaves slender ; stamens 6 ; 

 fruit linear-club-shaped ; carpels when ripe separating from below upward, 

 leaving a triangular axis, awl-pointed at ftase. — Marshes (usually brackish) 

 and bogs, Greenl. to the coast of s. Me. ; also inland along the St. John and 

 St. Lawrence R., Great Lakes and northwestw. (Eurasia.) 



ALISHACEAE (Water-plantain Family) 



Marsh herbs, xeith scape-like stems, sheathing leaves, and perfect, monoecious, 

 or dioecious flowers ; perianth of 3 herbaceous persistent sepals and as many 

 (often conspicuous) white deciduous petals, which are imbricate or involute in 

 bud; stamens 6 or more, included; ovaries numerous, distinct, 1-celled and 

 mostly 1-ovuled, becoming aclienes in fruit (in our genera) ; seeds erect, cam- 

 pylotropous. — Roots fibrous ; leaves radical, petiolate and strongly nerved with 

 transverse veinlets, the earlier sometimes without blade ; flowers long-pedicellate, 



