126 MEMOIES FROM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 



[Plate 50.] 



50. Polygonum Austinae Greene. 



Polygonum Aastinae Greene, Bull. Calif. Acad. Sci. 2: 212 (1885). 



Annual, low, glabrous, scurfy throughout. Stem mostly erect, .5-1.7 cm. long, 

 branched from the base, sparingly branched above, four-angled and somewhat four- 

 winged, scurfy especially below the nodes; leaves varying from ovate-lanceolate to oblan- 

 ceolate, .5-1.5 cm. long, .2-5 cm. broad, the upper ones reduced to bracts, acute, sessile, 

 revolute or flat, bright green beneath, midrib prominent on the lower surface, articulations 

 at the ocreae not conspicuous ; ocreae funnelform, 3-4 mm. long, oblique and at length 

 slightly lacerate ; inflorescence axillary, consisting of clusters with two or three flowers, 

 extending from near the base of the plant to the ends of the branches; pedicels 1-1.5 

 long, mostly deflexed ; calyx green, 2.5 mm. long, drooping, five-parted to near the base, 

 the segments narrowly oblong, obtuse, with whitish borders and a dark rib ; stamens 

 varying from five to eight, included; style about .5 mm. long, three-parted to the base; 

 achene triquetrous, 2.5-3 mm. long, ovoid or oblong, black, smooth and shining, some- 

 what exceeding the calyx at maturity. 



Northwest Territory to northern California and Wyoming. 



