POLYGONACEAE 



289 



13. R. persicarioides L. On sea shores: N. B. to Va. and 

 westward. Sometimes confused with the Old World R. 

 maritimus L. 

 N. Y. Eastern L. I. 



N. J. Middlesex Co.; reported from Monmouth and Ocean 

 counties. 



R. conglomeranis Mum, and R. salicifolius Weinm., have been reported, but it is 

 doubtful if they are really established. R. maiilimus L. has been collected as a waif. 

 R. elongalus Guss. is recorded from Southington, Conn. 



2. Polygonum [Tourn.] L. 



Stems and branches terete and usually striate. 

 Achenes much exserted from the calyx. 

 Plant prostrate; achene broad. 

 Plant erect; achene narrow. 

 Achenes included within the calyx; or exposed at the tip. 

 Sepals with white or pink margins. 



Pedicels not exserted from the ocreae. 

 Achenes with striate faces. 



Mature sepals over 3.5 mm. long; 



achenes acute. 

 Mature sepals less than 3.3 mm. 

 long; achenes acuminate. 

 Achenes with granular or nearly smooth 

 faces. 

 Plant prostrate; leaves broad; mature 



sepals over 3.5 mm. long. 

 Plant erect or nearly so; leaves 

 narrow; mature sepals less than 3.3 

 mm. long. 

 Pedicels exserted. 

 Sepals with yellowish or greenish margins. 

 Stems and branches angled. 



1. P. maritimum. 



2. P. exsertum. 



3. P. aviculare. 



4. P. neglectum. 



5. P. buxiforme. 



6. P. prolificum. 



7. P. atlanttcum. 



8. P. erectum. 



9. P. tenue. 



2. P 



maritimum L. In sands of the seashore: Mass. to Fla. 

 Also on the coast of Europe. 

 Conn. Reported but not definitely known. 



N. Y. Common along the south shore of L. I., less common on the 

 north shore; rare along the coast on S. I.; unrecorded elsewhere. 

 N. J. Uncommon along the sea coast, not recorded elsewhere. 

 Apparently never found far from sandy sea beaches. 



exsertum Small. Saskatchewan, south to 111., Mo. and 

 Neb. ; and along the Atlantic coast in brackish marshes, from 

 N. B. to N. J. 

 Conn. Rare along the coast in New Haven and Fairfield counties. 



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