104 



cix. POLYGONACEvE (baker AND WRIGHT). [Polygonum. 



1. P. alatum. 



2. P. aviculare. 



3. F. plebeium. 



amjpkibium. 

 Buchanani. 



6. P. strigosum. 



7. P. pedunculare. 



Herbs or shrubs, erect, prostrate or scandent. Leaves alternate ; ochrese 

 membranous, clasping the stem, often fringed with bristles. Flowers 

 usually fascicled in the axils of membranous bracts, fascicles often 

 arranged in terminal racemes, spikes, or panicles; pedicels articu- 

 lated. 



Species about 150, cosmopolitan. 

 *Flowers in heads or clusters (see also 6, strigosum). 

 Leaves ovate. Nutlet pitted .... 



Leaves linear or liiiear-oblonj^. 



Nutlet rugose, dull ...... 



Nutlet suiootli, shilling: ..... 



**Flowcrs in spikes, nicenies, or jjanicles. 



Leaves oblong, ll in. broad, glabrous . 

 Leaves ovate, 2 in. broad, glandular beneath . 

 Leaves lauceolate or oblong-lanceolate. 

 Racemes very short, in lax jianicles. 

 Leaves truncate at the base, hairy 

 Leaves cuneate at the base, glabrous 

 Racemes elongated, slender ; clusters of flowers 

 not congested. 

 Nutlet usually trigonous ; styles 3 . 

 Nutlet lenticular ; styles 2 .... 



Racemes elongated, more robust; clusters of 

 flowers congested. 

 Ochrea) with a herbaceous spreading limb. 

 Leaves liairy; biacts ciliatc 

 Leaves soon glabrescent ; bracts not ciliate . 

 Ochrca without a herbaceous limb. 



Nutlets trigonous ..... 



Nutlets lenticular. 



Leaves densely white hairy beneath. 



Bracts not ciliate .... 



Bracts ciliate ..... 



Leaves slightly hairy on the nerves and 

 margins only. 

 Ochrea^ glabrous. 



Leaves glamlular .... 



Leaves not glandular 

 Ochrea^ bristly. 

 Stamens included. 



Stem glabrous .... 



Stem i)nbescent'. 

 Stamens exserted .... 



Leaves quite glabrous .... 



17. P. TanganikcE. 



18. P. acuminatum. 



19. P. ergthropus, 



20. P. glabrum. 



1. P. alatum, Buck.- Ham. ex D. Don, Prodr. Fl. Nep. 72. 

 Annual. Stems very slender, naked, branched. Leaves ovate, acumi- 

 nate, membranous, about 1 in. long, narrowed suddenly to a short 

 winged petiole ; ochreae not ciliate. Heads of flowers 1-2 to a branch, 

 3 lin. in diam., usually subtended by a leaf ; bracts ovate, not ciliate ; 

 pedicels slender, hispid at the tip. Perianth eglandular, 1^ lin. long. 

 Stamens 7-8. Nut biconvex or trigonous, reticulated. — Spreng. Syst. 

 Yeg. cur. post. 154; Hook. f. Fl. Brit. Ind. v. 41. P. nepcdense. 



