188 COMMON CANADIAN WILD PLANTS. 



3. A. albUS, L. Flowers greenish, in small close axillary- 

 clusters. Stem law and spreading. — Roadsides. 



9, IHOKTES'lIA, Moquin. 

 M. tamarls'cina. Gray. (Acnida ruscocarpa, Gray.) A 

 tall smooth herb, with lanceolate or ohlong-ovate alternate 

 leaves on long petioles, and small clusters of greenish flow- 

 ers in interrupted spikes. — Wet places. 



Var. eoncatena'ta, Gray, {Acnida tuherculata, Moq^.) has 

 the flowers in the lower part of the stem in close clusters in 

 the axils of the leaves, '" 



Order LXXVIII. POLYGONA'CE.ffl. (Buckwheat F.) 



Herbs, well marked by the stipules of the alternate leaves 

 ^being in the form of membranous sheaths above the usually 

 swollen joints of the stem (these obsolete in one Genus). 

 Flowers usually perfect. Calyx 4-6-parted. Stamens 4-9, 

 inserted on the base of the calyx. Stigmas 2 or 3. Ovary 

 1-celled, with a single ovule rising from the base, forming 

 a little nutlet. 



Synopsis of the ticucra. 



* Flowers involucrate. Stamens 0. Stipules obsolete. 



1. ilrlog'uiiiiin. Involucre 4-8-tootlie(l, (he flowers exserted. r.alyx 



(i-parted, coloured (yellow in ours), enclosing the achcne.— N.W. 

 ^ly. 



* * Flowers not involucrate. Stamens 4-8. 



2. I'olyg'onuni, Sepals 5 (occasionally i), often coloured and petal- 



like, persistant, embracing the 3-anglcd (or sometimes flattish) 

 nutlet or achene. Flowers In racemes or spikes, or sometimes In 

 the axils. 



3. Ku'nicx. Sepals 8, tlie a outer ones herbaceous and spreading in 



fruit, the 3 inner (called valves) somewhat pelal-like and after 

 flowering, convergent over tl)e 3-anfflcd achene, often with a 

 grain-ltke projection on the back. Stamens li. Styles 3 Flowers 

 usually in crowded whorls, the latter in panicled racemes. 



4. Fagopy'ruiii. Caly.x 0-partcd, petal-liko. SHamous 8, with 8 yellow 



alands between tliem. Styles 3. Achenes 3-anglcd. Flowers wnite 

 m panicles. Leaves triangular heart-shaped or halberd-shaped ' 



