66 FOUNDATIONS OF BOTANY 



mostly solitary, on slender peduncles. Calyx bent in the shape of 

 a pipe, yellowish-green with a dark purple throat, limb unequally 

 3-lobed, rugose, reflexed. Anthers in pairs below the 3 spreading 

 lobes of the stigma. Capsule oblong. Stems sometimes 30 ft. long. 

 Rich woods S.* 



25. POLYGONACE.ffi;. Buckwheat Family. 



Herbs with alternate, entire leaves and usually with sheath- 

 ing stipules above the swollen joints of the stem. Flowers 

 apetalous, generally perfect, with a 3-6-cleft calyx, generally 

 colored and persistent. Fruit a compressed or 3-angled akene, 

 enclosed in the calyx. Seeds with endosperm, which does not 

 generally enclose the embryo. Stamens 4-12, on the base of 

 the calyx. <• 



I. RUMEX, L. 



Coarse herbs, many of them troublesome weeds. Flowers 

 small, usually green or greenish, generally in whorls borne in 

 panicled racemes. Calyx of 6 nearly distinct sepals, the 3 

 inner larger and more petal-like than the 3 outer, and one 

 or more of them usually with a little knob or tubercle on its 

 back. Stamens 6. Styles 3. Stigmas short, fringed. Fruit 

 a 3-angled akene, closely covered by the 3 inner calyx-lobes, 

 enlarged and known as valves. 



1. R. Acetosella, L. Sheep Sorkel. Erect annual or perennial 

 herbs with creeping rootstocks. Stem simple or branched, smooth. 

 Leaves petioled, narrowly halberd-shaped, usually widest above the 

 middle, the apex acute or obtuse, upper stem-leaves often nearly 

 linear and not lobed. Flowers dioecious, small, in terminal, naked, 

 panicled, interrupted racemes. Calyx greenish ; the pistillate pani- 

 cles becoming reddish. Fruit less than ^ in. long, granular, longer 

 than the calyx. A common introduced weed, in dry fields and on 

 sour soils. Foliage very acid.* 



2. R. verticillatus, L. Swamp Dock. Perennial, stem stout, 

 smooth, erect or ascending, 3-5 ft. tall. Lower leaves oblong, 

 obtuse at the apex and usually heart-shaped at the base, long- 

 petioled, often 12-18 in. long, upper leaves narrower and often 

 acute at both ends. Flowers perfect or somewhat monoecious, in 

 dense whorjs, pedicels slender, ^-| in. long, tapering downward, 



