POLYGON A ( K.I : 



305 



1. RHEUM. Rhubarb. 



Very large-leaved perennials, sending up stoul hollow flower-stalks in 

 early summer which bear smaller leaves with sheathing bases: sepals 6, all 

 alike, withering rather than falling, and persisting beneath i In- 3-wii 

 akene: stamens 9: styles 3. Old World. 



R. Rhaponticum, Linn. Rhubarb. Pie-plant. Pigs. 78, 79. Leaves 

 1 ft. or more across, the thick petioles eaten: Ms. white, in elevated panicles. 



2. RUMEX. Dock. Sobbei.. 



Perennial often deep-rooted plants with herbage hitter or sour: sepals 6, 

 the 3 outer large and spread in ir, the .'! inner (known as "valves") enlarging 



after flowering and one or i > of them often bearing a grain-like tubercle 



on the back : stamens 6, styles 3: flowers in pan- 

 icles or interrupted spikes. 



a. Docks : herbagi bitter: valves >tt-i> grain- 

 bearing: flowers mostly perfect: leaves 

 not arrow shapi /. 

 R. obtusifolius, I.inn. Bitter dock. Lower leaves 



oblong-cordate and obtuse, do! wavy: valve 



usually grain bearing. Weed from Europe. 



R. crispus, Linn. Curly dock. Leaves lanci 

 late, wavy or curled: all valves usually grain-bear- 

 ing. Weed from Europe. 



153. Bud isella. 



aa. So rf Is: 



herbagi sour: valves not grain bearing: flowers diacious: 

 i, ,i r. i arrow shapi d. 



R. Acetos611a, Linn. Common or sheep sorrel. Pig. 163. Low (1 ft. 

 or less): leaves mostly arrow-shaped al base: flow- 

 ers brownish, small, In a terminal panicle. Common 

 in Bterile fields. Europe. 



::. FAGOPYRUM. BucKWHl LT. 



Past-growing annual-, with Bomewhal trlangu 

 lar have-, and fragranl flowers in flattish, panicle- 

 like clusters: calyx of :, part-: Btamens 8: fruit a 

 triangular akene. <>hl World. 



F. escul6ntum, Moench. Common buckwheat. 

 Pig. 154. Leaves triangular arrow shaped, long peti 

 oled: flowers white, in a compound cluster: akene 

 with regular angles. Plour la made from the grain. 



F. Tataricum, Qaertn, India wheat. Blen- 



derer, the leaves Bmaller and re arrow shaped 



and -hoit petioled: ih.w. r- greenish or yellowish, In simple raceme 

 notched on the angles. Somewhat cultivated. 



i -i 



llelltlllll 



nkeiie 



I. POLYGONUM. Knotweed. Bmartwebd 



i.oa weedy plant-, or tome exotic ones tall and cultivated, blooming In 

 summer and fall, the small pinkinh or greenish flowers moatlj In rac< an 



T 



