PINK AND ROSE-COLORED FLOWERS 
Water Persicaria (Polygonum amphibium) . Buckwheat 
family. August, September. 
A stout Knotweed growing in water. The minute rose-colored 
flowers are in close spike. The five divisions of the calyx 
resemble petals; stamens five; the (two-parted) style projects. 
Leaves thick, oblong, with stalks. Ponds. Polygonum means 
many-jointed. 
Pink Knotweed (Polygonum pennsyhanicum) . Buck- 
wheat family. August, September. 
A common, branching Knotweed, enlarged at the joints, 
sometimes reaching a height of four feet. Flowers small, in 
dense spikes sometimes over an inch long, the five divisions of 
the calyx resembling petals. Leaves lance-shaped, long-pointed. 
Moist ground. Lady's Thumb (P. Persicaria) is similar but 
not more than two feet high, with a dark spot in the middle of 
the leaf. 
Knotgrass.* Door-weed (Polygonum aviculare). Buck- 
wheat family. 
An insignificant annual or perennial straggling weed. The 
tiny flowers have green calyxes with pinkish, five-lobed borders; 
no corolla. Leaves somewhat lance-shaped, practically without 
stalks. Dooryards and waste ground. Common. 
" The lowing herds 
Have ta'en their supper off the succulent herb 
Of knotgrass, dew-besprint." 
1 Inserted here rather than separate the members of this family, though 
the arrangement of its flowers should place it rather in Group IX. See 
also Moth Mullein (p. 60), of which one variety (albiflorum) has pinkish 
flowers, and Pale Corydalis (p. 222), whose clusters are racemose, and 
should, perhaps, rather have been included in this group. 
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