116 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 



[Plate 45.] 

 45. Polygonum camporum Meisner. 



Pohjijonum nimporum Meisuer in Mart. Fl. Bras. 5: 21 (1855) and in DC. Prodr. 

 14: 87. 



Polygonum aimporum var. horailc Meisner in Mart. Fl. Bras. 5: 22 (1855) and in 

 DC. Prodr. 14 : 87 ; Torrey, Bot. INIex. Bound. Surv. 178; A. Gray, Man. Ed. 6, 440. 



Perennial or sometimes annual, slender, suffruticose, glabrous, rarely glaucescent, 

 turning brown or black in drying. Stem erect, ascending or creeping at the base, 6-10 

 dm. long, nearly terete or more or less ridged, nearly simple or much branched and 

 straggling; leaves varying from linear-lanceolate to oblong, 1-3 cm. long, .1-.5 cm. broad, 

 sometimes oblanceolate, obtuse or acute, subsessile, fugacious or rarely somewhat per- 

 sistent, conspicuously nerved on the lower surface, flat or revolute ; ocreae funnelform, 

 3-5 mm. long, oblique and two-parted when very young, silvery, at length dark brown, 

 soon becoming much lacerate and falling away; inflorescence axillary, the clusters 

 several-flowered; pedicels slender, 2-3 mm. long; calyx greenish, 3 mm. long, five-parted 

 to near the base,, the segments oblong; stamens eight, included; style .4 mm. long, three- 

 parted to the base, included ; achene triquetrous, 3 mm. long, broadly ovoid, black or 

 dark-brown, smooth and shining. 



Nebraska to Louisiana and New Mexico. Also in South America. 



