130 FLORA OF. PHILADELPHIA. 



3. Flowers in axillary clusters; steins more or less wiry, not twiming.. 



Plant prostrate; achene invented by, the calyx. ■„., \ 



Leaves mostly acute; sj;yle 3-parted ,to below the middle. , 



13. P. avHculare'.' 

 Leaves mostly obtuse; style 3-;parted to i the base. , •■, ,o, ■<. ,,;. ... 



, 14;, p. uporau.. 



Plants prostrate, achene protruding beyond the calyx. 



Mi--- ,j" 15. P. maritimvim,.' 



, Plants, erecjt or ascending, rather, stoirfc. ; . , , ., >. 



Leaves oval, oblong, or obovate, persistent. . , 



16. P. erecium. 

 -Leaves narrowly lanceolate ,or linear-oblong, persistent. i, i,l < 



17. P. ramosissvmum. 

 Plants strictly erect and very slender. ' 18. P. tenue. 



4. Flowers in axillary and terminal clusters, racemes or panieled racemes; 



stems mostly twining. > ■ ■..,'. ' ' , . ■ , 



Stems twining; herbaceous vines. 



Outer segments of the calyx unchanged or keeled in fruit. 

 Achene granular and dull, ocreae not bristly. 



.)...', 19. P. Convolvulus. 



Achene smooth ,an,d shining, ocreae bristly. 



20. P. cilinode. 

 Outer segments of the calyx conspicuously winged in fruit. 

 Calyx wings not incised. 21. P. scandens. 



Calyx wings incised. > , > i 22. P. cristatum. 



Stems stout, erect, ta,llj outer calyx-segments winged, in fruit. 



' ' " 23. P. Zuccarinii. 



5. Flowers in capitate clusters or racemes; stems climbing by recurved 



prickles. 

 Leaves sagjttat^; achene jangled. , , ,,,,2,4. .P. sagittatwm. 



Leaves halberd-shaped ; achene lenticular. 25. P. arifoUum. , 



■u' ■ ■ '..■•, i . ■ '■■ ■ "."' "'■"! iv ,-,-f ^/' ■!'-} : 



1. Polygonum amphibium L. M. p. 360. Ponds. Summer. '■ i, * 



Montgomery— Shanmonville (Cn). Lancaster — York Furnace ;1 (Cr.) 

 (He.) (Li.): Northampton— (P.). Dauphin— Steeltoh (Wn.). ' 

 Hunterdon— (C). , ,. mi . Mi , iM . , , f 



New Castle -* Cherry Island, Holly Oak, Vandyke, etc. 

 ~L 2. Polygonum emersu'M (Michi.) ' Britton. 'Ml p. 360. Swamps and 

 moist soil. Summer. 

 Bucks — Sellersville (Fr.). . Delaware— Tinicum, T. C. Palmer (Fu.). 

 Chester— (P.). Lancaster — (P.). Northampton— Haston, Porter (B. C) . 

 ' ■'■' Gloucester — Repaupo (He.).' Mercer — Below Trenton (C). Hun- 



terdon— Bulls. Isjand (C). 

 3. Polygonum incarnatum Ell. M. p. 360. Wet soil. Summer. 

 'Lancaster— (P.). Northampton— (V.). Dauphin— (P.). 

 Camden— -Banks of Delaware (C.), ]M 

 ^- .4. Polygonum lapathifolium L. M. p. 361. Waste places. Summer. 



Philadelphia — Fairmount Park (Ja.). Montgomery — Shannonville 

 (Cr.). Delaware— Lausdpwne, (0-i.)* Chester— West' Chester (P.). 

 Cape May— Anglesea (He.) (Li.) 



5. Polygonum Pennsylvan'icum H M. p. 361. Moist soil. Summer. 



6. Polygonum Peksioaria L. Lady's Thumb. M. p. 361. Waste places. 



Summer. ' ' 



7. Polygonum Careyi Olney. M. p. 362. Marshes. Summer. ,,,!,, 



Burlington— Pemberton ((\), Brown Mills (He.) (Li.). Camden — 



