116 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 
[Piare 45.] 
45. Polygonum camporum Meisner. 
Polygonum camporum Meisner in Mart. Fl. Bras. 5: 21 (1855) and in DC. Prodr. 
Wet le 
Polygonum camporum var. boreale Meisner in Mart. Fl. Bras. 5: 22 (1855) and in 
DC. Prodr. 14: 87; Torrey, Bot. Mex. 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 em. long, .1-.5 em. 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. 
