Polygonacce—Polygonum. 383 
Orprr LXXXIX._POLYGONACEAR. 
Herbs (or rarely shrubs) with alternate simple leaves and 
sheathing often fringed stipules. Flowers usually herma- 
phrodite, on jointed pedicels. Perianth inferior, composed of 
3 to 6 petaloid or green, free or united, persistent segments, 
imbricate in bud. Stamens 3 to 12, or more. Fruit a dry 
1-celled 1-seeded indehiscent achene or nut, usually enveloped 
in the perianth. Seeds erect, albuminous. This order com- 
prises about 30 genera and 500 species, found in all regions, 
but most abundantly in the north temperate zone. The Docks 
and Knotweeds represent them only too well in this country. 
1. POLYGONUM. 
Herbs or undershrubs with alternate stipulate leaves and 
racemose, paniculate or spicate bisexual flowers. Bracts 
ochreate. Perianth usually coloured, of 5 nearly equal seg- 
ments, the three outer sometimes enlarging over the flattened 
or trigonous fruit. Stamens 5 to 8; anthers versatile. The 
species are estimated at 150, and are dispersed all over the 
world. There are twelve indigenous species, mostly weeds. The 
generic name is composed of voAv, many, and yévv, knee, from 
the numerous joints of the stems. 
1. P. cuspidatum, syn. P. Siebdldii.—This is a tall hand- 
some perennial, belonging to the foliage section of ornamental 
plants. It grows from 4 to 8 feet high, and bears an abun- 
dance of large somewhat distichous oval-oblong cuspidate 
petiolate leaves. Flowers white, in drooping racemes, suc- 
ceeded by scarlet fruits. A native of Japan, flowering in 
Summer. 
2. P. Brunonis.—A dwarf perennial species, rarely exceeding 
a foot in height. Leaves petiolate, oblong-lanceolate, acute, 
with a cartilaginous margin. Flowers rosy red, in dense ter- 
minal spikes appearing in Summer. Northern India. 
3. P. Bistérta. Bistort or Snake-root.—This is a rare 
indigenous species, and the handsomest we have. Leaves 
chiefly radical, large, oblong or ovate-obtuse, glaucous beneath, 
on long petioles. Flower-scapes erect, furnished with a few 
sessile leaves, and terminated by a solitary erect dense spike of 
reddish pink flowers, produced from June to September. 
