62 MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA COLLEGE. 
[PLATE 18. ] 
18. Polygonum longistylum Small. 
Polygonum longistylum Small, Bull. Torr. Club, 1: 169 (1894). 
Annual or perennial, slender, glabrous except the upper branches and peduncles. 
Stem erect, 85-6 dm. long, branched throughout, somewhat enlarged at the nodes, more 
or less channeled, becoming woody below; leaves varying from lanceolate to narrowly 
lanceolate or sometimes ovate-lanceolate, 3-10 em. long, .56-2 em. broad, acuminate at 
both ends, undulate, more or less ciliate, somewhat crisped, petioled; petioles .5-1.2 em. 
long; ocree cylindric, or funnelform at branching nodes, truncate, entire, thin, brittle, 
soon falling away; inflorescence terminal, paniculate, glandular and pubescent, consist- 
ing of spicate often geminate racemes; racemes cylindric, 2-8 cm. long, 1 em. thick, 
erect, many-flowered but not dense, conspicuous; ocreole funnel-form, 2—2.5 mm. long, 
their margins hyaline; pedicels slender, 3 mm. long, somewhat angled; calyx mostly 
lilac, 4 mm. long, five-parted to below the middle, the segments oblong, obtuse; stamens 
oO) 
varying from six to eight, included; style 3-3.5 mm. long, two-parted to below the mid- 
dle, slender, conspicuously exserted, the stigmas black; achene lenticular, 2.5 mm. long, 
broadly ovoid, long-pointed, slightly gibbous on the sides, dark brown or black, slightly 
granular, somewhat shining or dull. 
Southern Missouri, south to Louisiana and New Mexico. 
