POLYQOXACEiE. (BUCKWHEAT FAMILY.) 105 



2. A. umbellata, Lamb. (Pink Sand-Verbena.) Annual; stems decumbent, 

 leaves oblong or ovate, attenuate at base into slender petioles; flowers pink. 



ORDER CHESOt'ODIAVEJE \% represented by introduced weeds of tho genus CAenopodiMm, viz.: 

 Goose/oot, Lanb's-quarters, Pigwend, Jerusalem Oak, Wormseed. etc. SjUcornia (Glasswort) grows in salt 

 marshes, and may be known by its fleshy leafless jointed stems, with opposite branches. 



Order 50. POLYGONACEiE. 



Ilerbs, -svitli alternate leaves, and stipules in the form of slieaths, or obsolete, above 

 the swollen joints of the stem; the flowers mostly perfect, with a more or less persistent 

 calyx, a 1 -celled ovary, bearing 2 or 3 styles or stigmas, and a single seed. Stamens 4-12 

 inserted on the base of the 3-6-cleft calyx. Leaves usually entire. 



1. POLYGONUM, L. 



Calyx o-parted; the divisions petal-like, persistent in fruit, and surrounding the 



usually 3-angled akene. Stamens 3 to 8. Styles or stigmas 2 or 3.— Herbs with small 



flowers on jointed pedicels. 



* Flowers in spikes. 



1. P. acre, HBK. (Water Smartweed.) Leaves lanceolate with sheathing 

 fringed stipules; calyx pinkish, dotted; stamens 8; style 3-parted. — Wet places. 



* Greenish white flowers axillm-y ; staviens usually 5 ; stiymas fjlohose nearly sessile. 



2. P. aviculare, L. (Knotgrass, Door-weed.) Prostrate or spreading; leaves lan- 

 ceolate, sessile. 



3. P. maritimum, L. (Coast Knotgrass.) Glaucous; leaves thickened, the stipules 

 large; flowers larger than the last. 



2. RUMEX, L. 



Calyx of 6 sepals; the three outer herbaceous, spreading in fruit; the three inner larger, 

 somewhat jjetaloid, covering the akene in fruit (then called valves), and often bearing 

 grain-like appendages on the outside. Stamens 6. Styles 3; stigmas tufted. — Introduced 

 weeds with small greenish flowers crowded and whorled in panicled racemes. 



1. R. crispus, L. (Curled Dock.) Leaves with wavy margins; heart-shaped valves 

 with grains. A tall weed, in moist cultivated ground. 



2. R. maritimus, L. (Golden Dock.) A smaller plant; the valves of the fruiting 

 calyx bearing 2 or 3 awns on each side, and a large grain on the back, yellowish or orange- 

 colored. — Sea coast. 



3. R. acetosella, L. (Sheep Sorrel. ) A low weed with mostly halberd-shaped 

 leaves; flowers dioicious. 



3. ERIOGONUM, Michx. 



Flowers borne in a many-to-few-ilowered calyx-like involucre of united bracts; the 

 pedicels exserted, jointed to the flower, with bractlets at the base. Calyx corolla-like; 



