118 memoirs from the department of botany of columbia college. 



[Plate 46.] 

 46. Polygonum Douglasii Greene. 



Poh/goimm tenuc Engelmann; A. Gray, Proc. Acad. Phila. 75 (1863), not Michaux; 



S. Watson, Bot. King's Exp. 315, Bot. Calif. 2:12; Coulter, Man. Bot. Rocky Mt. Reg. 319. 



Polygonum fenue var. coni'mune Engelmann; A. Gray, Proc. Acad. Phila. 75 (1863). 



Polygonum Doughmi Greene, Bull. Calif. Acad. Sci. 1 : 125 (1884), Fl. Francis. 134. 



Annual, slender, glabrous except the more or less scabrous nodes, sometimes glau- 

 cescent. Stem erect, 2-4 dm. long, nearly simple or branched from the base or through- 

 out, lax or strict, almost terete or somewhat ridged ; leaves oblong or narrowly lanceolate, 

 1-5 cm. long, .2-.8 cm. broad, obtuse, acute or cuspidate, subsessile or sessile, acuminate 

 at the base, rather thin, flat, or somewhat revolute, with no lateral impressions, joined to 

 the ocreae by conspicuous articulations; ocreae funnelform, obhque, 10-14 xx\ra. long, two- 

 parted, at length lacerate ; inflorescence axillary, the clusters several-flowered or occasion- 

 ally only a single flower at a node ; pedicels 2-3 mm. long, reflexed and at length de- 

 flexed ; calyx greenish, 3-4 mm. long, drooping, five-parted to near the base, the segments 

 oblong, obtuse, with whitish or rose-colored margins and a dark rib in the middle; 

 stamens eight, included; style .3 mm. long, three-parted to near the base, the segments 

 somewhat divergent and slightly protruding beyond the calyx at maturity ; achene tri- 

 (juetrous, 3-4 mm. long, oblong or rarely ovoid-oblong, black, smooth and shining. 



Northwest Territory to California, New Mexico and Indian Territory, east to 

 Ontario, Vermont and New York. 



Polygonum Douglasii montanum Small. 



Polygonum tenue var. latifolium Engelmann, Proc. Acad. Phila. 75 (1863), not P. 

 avicnlare var. latifoliuvb Michx. (1803); S. Watson, Bot. King's Exp. 315; Coulter, Man. 

 Bot. Rocky Ut. Reg. 319. 



Polygonum Douglasii var. latifolium Greene, Bull. Calif. Acad. Sci. 1 : 125 (1884), 

 Fl. Francis. 134. 



Stout, xwoYQ or less fleshy, glaucescent; stem erect, .5-2.5 dm. long or sometimes pros- 

 trate, simple or sparingly branched from near the base ; leaves oblong or oblanceolate, 

 1-4.5 mm. long, 2-12 mm. broad, apiculate, sessile; inflorescence m.ostly towards the 

 ends of the branches; achene triquetrous, 3 mm. long, oblong, black, smooth and shining. 



iVrizona to California and northward in the higher mountains. 



