100 
866. P. hydropiperoides, Michx. Mild Water pepper. 
Aquatic, or in muddy places; frequent southward and north to 
Riverside, elsewhere infrequent. July 25th — September. 
867. P. hydropiper, L. Common Smartweed. Water-pepper. 
Moist or swampy places; frequent and scattered. July 20th — 
October. 
868. P, acre, H. B. K. Water Smartweed. 
Swamps, ditches and borders of lakes and rivers; frequent south- 
ward. July — September. (B.) 
869. P. virginianum, L. 
Shaded rich woods ; common. August. 
870. P. sagittatum, L. Arrow-leaved Tear-thumb. 
Damp or wet places, Lake County, Ind. ; frequent, elsewhere less 
common. August. 
A form is occasionally found with the stem rounded, and with the 
reflexed prickles scattered. 
871. P. convolvulus, L. Black Bindweed. Knot Bindweed. 
Fields and waste grounds ; frequent from Riverside, south through 
the Calumet Region, and to the lake shore ; infrequent elsewhere. 
June — September, usually in July. 
872. p 8 dumetorium, L , var. seandens. Gray. Climbing False- 
Buckwheat. Hedge Bindweed. 
Moist woods and shaded banks ; frequent. August — September. 
FAGOPYRUM, Tourn. 
878. F. esculentum, Moench. Buckwheat. 
Old fields, escaped from cultivation ; infrequent. June — August. (B.) 
POLYGONELLA, Michx. 
874. P. articulata, Meisner. Joint-weed. 
Polygonum articulatum , Gray. 
Bluffs near Evanston; rare. Miller’s, Ind,, Bastin! Sand hills, 
Tolleston, Ind., Hill. 
White-flowered form, Miller’s, Ind., Hill! 
PODOSTEMACE.ZE. 
PODOSTEMON, Michx. 
875. P. ceratophyllus, Michx. River-weed. Thread-foot. 
South Chicago, University of Chicago Herb. (B. P.) 
