128 MEMOIRS FEOM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 



[Plate 51.] 

 51. Polygonum minimum S. Watson. 



Polygonum minimum S. Watson, Bot. King's Exp. 315 (1871), Bot. Calif. 2: 11; 

 Coulter, Man. Bot. Rocky Mt. Reg. 318; Greene, Fl. Francis. 133. 



Polygonum Torreyi S. Watson, Am. Nat. 7: 664 (1873), Bot. Calif. 2: 12. 



Annual, small and slender, somewhat scurfy but glabrous. Stem erect or spreading, 

 .3-3 dm. long, wiry, simple or branched mostly from the base, somewhat angled; leaves 

 mostly obovate, sometimes oblong or ovate, .5-1.8 cm. long, .2-7 cm. broad, acute or 

 apiculate, subsessile, acuminate at the base, more or less glaucescent, evenly distributed 

 or crowded at the ends of the branches, not much reduced above, joined to the ocreae by 

 conspicuous articulations; ocreae funnelform, oblique, 1-4 mm. long, brittle, dentate- 

 lacerate ; inflorescence axillary, consisting of clusters bearing several flowers and extend- 

 ing throughout the plant; pedicels slender, 2-3 mm. long; calyx greenish, 1.5-2 mm. 

 long, five-parted to near the base, the segments paler and often with rose-colored margins ; 

 stamens varying from five to eight, included; style .2 mm. long, three-parted to below the 

 middle, included; achene triquetrous, 2-2.3 mm. long, varying from oblong to oblong- 

 ovoid, black, smooth and shining, at maturity somewhat protruding beyond the^ calyx. 



Northwest Territory to California and Utah. 



