34 
Spring Flora of Oklahoma 
FAMILY 17. POLYGONACEiE. Buckwheat Family. 
Herbs with alternate, entire leaves, and usually with 
sheathing stipules above the swollen joints of the stem. 
Flowers apetalous, generally bi-sexual, with a 3-6-cleft 
calyx, generally colored and persistent. Fruit a com¬ 
pressed or 3-angled achene, inclosed in the calyx. Seeds 
with endosperm, which does not generally enclose the 
embryo. Stamens 4-12, on the base of the calyx. 
Stigmas tufted; sepals of the inner row usually ac¬ 
crescent. 
Calyx 6-parted; style 3-parted; achene 3-angled. 
I. Rumex. 
Stigmas capitate, 2-cleft or toothed; sepals of the 
outer row often accrescent or reflexed. 
II. Polygonum. 
I. RUMEX L. 
Annual or perennial herbs with grooved and usually 
branched stems of various habits. Leaves entire or un¬ 
dulate, flat or crisped. Ocreae cylindrical and fugacious. 
Inflorescence of simple or compound racemes. Calyx 6- 
parted, the inner 3 parts usually developing into wings in 
the fruit. Stamens 6. Style 3-parted. Flowers greenish, 
small, crowded in panicled racemes. 
1. Leaves hastate; flowers dioecious; foliage acid; low 
species. 
A. Inner sepals not developing wings in fruit; achene 
granular. 1. R. Acetosella. 
2. Leaves not hastate; flowers perfect or polygamo- 
dioecious; foliage scarcely or not at all acid; tall 
species. 
