384 I'OLYGOXACE^. (BUCKWHEAT FAIIILY.) 



sessile. Stigma capitate or many-cleft. Utricle indehiscent, 1-seeded, included 

 in the calyx. Seed vertical. Radicle ascending. — Woolly or hairy annuals. 

 Leaves opposite. Spikes opposite, and terminating the naiied peduncle-like 

 summit of the stem. 



1. P. Floridana, Moquin. White-tomentose or woolly ; stem erect, sim- 

 ple or branched ; leaves varying from linear to oblong ; spikes ovate or oblong, 

 lengthening with age ; bracts mostly blackish, shorter than the woolly calyx ; 

 style short ; stigma capitate ; fruiting calyx round-ovate, compressed, toothed 

 along the margins, and minutely tubercled at the base. (Opiotheca Floridana, 

 iVutt.) — Dry sandy places, Georgia, Florida, and westward. July- Sept. — 

 Stem j°-3° higli. Spikes solitary, few, or numerous. 



Order 110. POLYGON ACE7E. (Bucka\tieat Family.) 



Herbs, shrub.'!, or (tropical) trees, with simple mostly alternate and 

 stipulate leaves, and perfect or dioecious flowers. — Calyx 3 - 6-clefl, or 

 3 - 6-sepalous, persistent. Stamens 4-12, inserted on the base of the 

 calyx : anthers 2-celled. Ovary single, 1-cclled, with the solitary ortho- 

 tropous ovule erect from the base of the cell. Styles 2-3, distinct or 

 partly united. Fruit (achenium) lenticular or 3-angled, rarely ovoid. 

 Embryo mostly on the outside of mealy albumen. Radicle pointing 

 upward. — Stipules sheathing, annular, or wanting. 



Synopsis. 



Suborder I. POLYGONE^E. Involucre none. Calyx 5-clefl or 

 5-sepalous. Stamens 4-9 (mostly 5 - 8). Ovules sessile. Embryo 

 curved on the outside of the albumen, rarely straight in its centre. 

 Stipules sheathing. 



# Calyx 5-.sepalous, the inner sepals erect, mostly enlarged in fruit. 



1. EUMEX. Calyx green, often grain-bearing. Stigmas many-cleft. 



2. POLYGONELLA. Calyx coroUa-like. Stigma entire. 



* * Calyx 5-sepalous, the sepals all erect, unchanged in fruit, free from the achenium. 



3. POLYGONUM. Sepals entire. Embryo curved on the outside of the albumen. 



4. TinrSANELLA. Inner sepals fimbriate. Embryo straight at the side of the albumen. 



• » * Calyx 5-parted, the tube enlarged and' fleshy In fruit, and partly united with the 



achenium. 



5. COCCOLOBA. Achenium ovoid or globose. Trees. 



Suborder IT BRUNNICHIE^E. Involucre none. Calyx 5-parted, 

 the tube enlarged and indurated in fruit. Stamens 8. Ovule borne on 

 a slender stalk. Embryo at the margin of the albumen. Stipules none. 



6 BRUNNICHIA. Pedicels winged In fruit. Climbing shrubs. 



