alismace^e. (water-plantain family.) 437 



Suborder I. JUNCAGINEiE. The Arrow-grass Family. 



1. TBIGLOCIIIN, L. Arrow-grass. 



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

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

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

 into 3-6 carpels, which separate from a central axis. — Leaves rush-like, fleshy, 

 sheathing the base of the wand-like naked and jointless scape. Flowers small, 

 in a spiked raceme, bractless. (Name composed of rpeis, three, and y\(o\iv, 

 point, from the three points of the ripe fruit in No. 1.) 



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

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

 angular axis, and aid-pointed at the base. 1J. — Marshes, both fresh and brack- 

 ish, New York to 111., and northward. Aug. (Eu.) 



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

 fruit ovate or oblong, acutish, of 6 or rarely 5 carpels which arc rounded at the base 

 and slightly grooved on the buck; the edges acute, y. — Salt marshes along the 

 coast ; salt springs, Salina, New York ; shore of the Great Lakes, and north- 

 ward. — Var. elXtum (T. datum, Nutt.) 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. SCIIEUCIIZERIA, L. Schecciizeria. 



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 fiat sessile stigmas, in fruit 

 forming 3 diverging and inflated 1 -2-seedcd 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, terminated by a loose raceme of a few flowers, with sheathing 

 bracts. (Named in honor of the two brothers Scheuchzer, distinguished Swiss 

 botanists.) 



1. S. palustl'is, L. — Peat-bogs, New England to Penn., Illinois, and 

 northward; rather rare. July. (Eu.) 



Suborder II. AL.ISHIJELE. The Water-Plantain Family 



3. ALISMA, L. Water-Plantaix. 



Flowers perfect. Petals involute in the bud. Stamens definite, mostly G. 

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

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

 Leaves all from the root, several-ribbed, with connected veinlcts. Scape with 

 whorled paniclcd branches. Flowers small, white or pale rose-color. (The 

 Greek name; of uncertain derivation.) 



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