POLYGONACEvE. (buckwheat FAMILY.) 4l9 



2. PAGOP'i'RtrM, Tourn. Bdckwiieat. 



Calyx petal-like, equally 5-parted, withering and nearly unchanged in fruit. 

 Stamens 8. Styles 3 : stigmas capitate. Achenium S-sided, longer than the 

 calyx. Embryo large, in the centre of the albumen, which it divides into 2 parts, 

 with very broad and foliaceous plaited and twisted cotyledons. — Annuals, with 

 triangular-heart-shaped or halberd-shaped leaves, semicylindrical sheaths, and 

 corymbose racemes or panicles of white flowers, often tinged with green or rose- 

 color. (Name, (prfyos, the beech, and irvpdf, wlieat, from the shape of the grain 

 being that of the beech-nut ; whence also the English name Bwiwheat, ft-om 

 the German 33ucf(e, beech.) 



1. F. EscuLENTUM, Moench. (Buckwheat.) Smoothish; flower with 8 

 honey-bearing yellow-glands interposed between the stamens; the fruit acute 

 and entire. (Polygonum Fagopyrum, L. ) — Old fields, remaining as a weed 

 after cultivation, and escaping into copses. June -Sept. (Adv. from Eu.) 



3. OXYRIA, Hill. Mountain Sokrel. 



Calyx herbaceous, of 4 sepals ; the two outer smaller and spreading, the two 

 inner broader and erect (but unchanged) in fruit. Stamens 6. Stigmas 2, ses- 

 sile, tufted. Achenium lenticular, tliin, flat, much larger than the calyx, sur- 

 rounded by a broad and veiny wing. Seed flattened in the opposite direction 

 from the wing. Embryo straight, occupying the centre of the albumen, slender. 

 — Low alpine perennials, with round-kidney-form and long-petioled leaves 

 chiefly from the root, obliquely truncate sheaths, and small greenish flowers 

 clustered in panicled racemes on a slender scape. (Name from o|i;'r, sour, in 

 allusion to the acid leaves, like those of Sorrel. ) 



1 . O. digyiia, Campdera. Leaves all round-kidney-form, usually notched 

 at the end ; fruit orbicular. — Alpine region of the White Mountains, New 

 Hampshire, Oakes, &c., and high northward. (Eu.) 



4. EUMEX, L. Dock. Sokkkl. 



Calyx of 6 sepals ; the 8 outer herbaceous, sometimes united at fhe base, 

 spreading in fruit ; the 3 inner larger, somewhat colored, increasing after flow- 

 ering and convergent over the 3-angled achenium, veiny, often bearing a grain- 

 like tubercle on the back (in fruit called valves). Stamens 6. Styles 3; 

 stigmas tufted. Embryo slightly curved, lying along one side of the albumen, 

 slender. — Coarse herbs, with small and homely (mostly green) flowers, which 

 are crowded and commonly whorled in panicled racemes ; the petioles somewhat 

 sheathing at the base. (The ancient Latin name of these plants; of unknown 

 etymology.) 



§ 1. Dock. Flowers perfect or monceciousbj polygamous: herbage not sour: none 



of the leaves halberd-shaped. (Flowering through the summer.) 



* Perennials, 2° - 7° high : valves not bearing bristles. 



■1- Valves {large, 3" broad, thin) all naked or one with a small grain. 



1. R. PATiiiNTiA, L. (Patience Dock.) Avery tall species, with ovate- 

 oblong and lanceolate leaves, those from the root 2° -3° long, and one of the 



