Fig. 406: Polygonum bistortoides: a, stipular leaf sheath, x 2; b, habit, showing 

 rhizome, basal leaves, and stem with cauline leaves and solitary spike, x 1/3; c and d, 

 mature achenes (cross section), x 6; e, mature achene, x 6; f, part of flowering spike, 

 showing the long-pediceled flowers exserted from hyaline sheathlike bracts, x 4; g, 

 rootstock, x %; h, pistils, the style 3-cleft, x 4; i. perianth, spread open, showing the 

 exserted stamens arising from glandular disk just below sinuses or from individual 

 glandular lobes, x 4. (From Mason, Fig. 197). 



