ALISMACEiE — HYDROCHARITACEiE 9 



1. TRIGLOCHIN. Arrow Grass. 

 Perianth 6-parted, greenish; stamens 3-6, with short filaments; 

 pistil a 3 or 6-ceIied ovary, splitting when ripe into 3 or 6 carpels 

 around a central axis. Low herbs with rush-like leaves sheathing 

 the scape at the base. 



1. T. maritima, L. ■ 



Scape 6 in.- 2 ft. high; leaves rather fleshy ; carpels mostly 6-grooved on 

 / the back. Wet alkaline soil, Man.-Alta. 



2. T. pallistTis, L. 



Scape 2-18 in. high;, leaves slender. Marshes, Alta. 



VIII. ALISMACE.^ (Water-plantain Family). 



Marsh herbs with scape-like stems and radical petiolate leaves, 

 the petiole sheathing the stem at the base; perianth of 3 herbaceous, 

 persistent sepals, and SVhite, deciduous petals; stamens 6 or more; 

 ovaries distinct, 1-celled, and usually 1-ovuIed. 



1. SAGITTARIA. Arrow-head. 



Sepals spreading in fruit; petals imbricated in the bud; ovaries 

 crowded on a globular receptacle forming winged achenes when ripe. 



1. S. latifSlia, WiUd. 



Glabrous; scape angled; petals waxy white; lower whorls of flowers 

 fertile; leaves mostly arrow-shaped. In water or wet places, easily recog- 

 nized by its arrow-shaped leaves and large white flowers. , Common and 

 exceedingly variable, Man.-Alta. 



2. ALISMA. Water Plantain. 



Flowers small, the whitish petals rolled inwardly in the bud; 

 ovaries many, in a circle on the flattened receptacle; scape with 

 whorled panicled branches'. 



1. A. PlantSgo-aquatica, L. 



Perennial, from a strong corm; leaves ovate orBblong, acute, and some- 

 times heart-shaped at the base, somewhat resembling those of the plantain ; 

 panicle very loose. Common in shallow water, Man.-Alta. 



IX. HYDROCHARITACE.ffi (Frog's-bit Family).. 



Aquatic herbs with regular perfect or dioecious flowers; stamens," 

 when present, 3-12, united in our species; stigmas 3; fruit ripening 

 under water. 



