WATER-PLANTAIN FAMILY. 319 



minute scales interposed, the lower of pistils, each ovary with a few small 

 scales at its base, the whole ripening into a spherical head of small nuts, 

 which are wedge-shaped below and with a pointed tip. 



1. TYPHA, CAT-TAIL FLAG. (From Greek word for /en, in which 

 these plants abound.) Fl. early summer, y. 



T. Iatif61ia, Common C. or Reed-Mace ; with flat leaveS, these and the 

 stem 6°- 10° high ; no interval between the sterile and fertile part of the si)ike. 



T. angustifblia, Narrow-leaved C. Less common, smaller ; leaves 

 narrower, more channelled toward the base ; commonly a space between the 

 sterile and the fertile part of the spike. 



2. SPARGANIUM, Bur-TIeed. (Name from Greek for a fillet, alluding 

 to the ribbon-shaped leaves.) Fl. summer. 2/ 



S. eurycarpum, Great B. Border of ponds and streams, 3° -5° high, 

 with panicled-spiked heads, the fertile when in fruit Ij" thick, the nuts broad- 

 tipped ; stigmas 2 ; leaves |' - 1' wide, flat on upper side, keeled and concave- 

 sided on the other. 



S. simplex, Smaller B. Only N. : in water ; erect, sometimes floating, 

 l°-2° high, mostly with a simple row of heads; leaves narrower; stigma 

 simple, linear, as long as the style ; nuts tapering to both ends and with a 

 stalked base. 



S. minimum, Smallest B. Mostly with lea*es floating in shallow 

 water (6'- 10' long) and flat; heads few; stigma simple, oval; nuts oval, 

 short-pointed and short-stalked. 



11. PETALOIDEOUS DIVISION. Flowers not on a spadix, 

 with a perianth (calyx and corolla), all or part of it usually colored. 



114. ALISMACE-ffil, WATER-PLANTAIN FAMILY. 



Marsh herbs, with flowers on scapes or scape-like steins, in pani- 

 cles, racemes, or spikes, with distinct calyx and corolla, viz. 3 se- 

 pals and 3 petals, and from 3 to many distinct pistils ; stamens on 

 the receptacle. Juice sometimes milky. The genuine Alismaceae 

 have solitary ovules and seeds, and wholly separate pistils. Some 

 outlying related plants differing in these respects are annexed. 



L ARROW-GRASS FAMILY. Calyx and corolla colored 

 alike (greenish). Anthers turned outwards. Ovaries 3 partly 

 united, or a single 3 - 6-celled compound pistil. Leaves petiole-like, 

 without a blade. 



1. TRIGLOCHIN. Flowers perfect, small, in a slender spike or raceme, bract- 



less. Calyx and corolla deciduous. Stamens 3 or 6, with oval anthers on 

 short filaments. Ovary 3 -6-celled, splitting when ripe from the central axis 

 into as manT,r closed and dry seed-like 1-seeded cells: stigmas sessile. 



2. SCHEUCHZLRIA. Flowers perfect, few and rather small, in a loose bracted 



raceme. Sepals and petals oblong, persistent. Stamens 6, with finear an- 

 thers. Pistils 3, with globular 2 - 3-ovuled ovaries slightly united at base, and 

 diverging in fruit, forming 3 turgid pods. Stigmas flat, sessile. 



II. WATER-PLANTAIN FAMILY proper. Calyx of 3 

 persistent green sepals. Corolla of 3 deciduous white petals. An- 

 thers turned outwards. Ovaries many, tipped with short style or 

 stigma, 1-ovuled, becoming akeues in fruit. Leaves sometimes only 

 petioles, commonly with distinct blade, when the nerves or ribs 

 are apt to be more or less joined by cross veins or netted. 



