HITCHCOCK PLANTS OF AMES, IOWA. 5 I 5 



R. VERTiClliliATUS, L. Spec. 



Around ponds and ditches; abundant. 

 R. cbispus, L. Spec. 



Roadsides and waste places; common. 

 R. maritimos, L. Spec. 



Abundant on the borders of Cairo lake. 

 R. Acktosella, L. Spec. 



Pastures; infrequent. 

 Polygonum avictlare, L. Spec. 



Yards and roadsides; common. 



In dry soil it is prostrate-spreading: in damp places, erect. 



P. ERECTUM, L. Spec. 



Roadsides : common. 



P. ramosissimum, Michx. Fl. 



Roadsides; frequent. 

 P. lapathifolium, L., var. incarnatum, (Ell.) Watson in Gray, 

 Man. 6th ed. — P. incarnatum. Ell. Sk. i. 

 Damp places; common. 



P. Pennsylvanicum, L. Spec. 



Damp places: common. 

 P. AMPHIBTUM, L. Spec. 



Ponds ; infrequent. 

 P. Muhlenrergii, Wats. Proc Amer. Acad. Sci. xiv. 1879. 



Low and often sandy soil; abundant, 



I have not been able to satisfy myself that P. terreatre. (Willd.) B. S. P. Cat 

 P. atnphibium. L., var. terreslre,W"\l\d. Spec, ii.) should be used. 



P. Hartwrightii, Gray, Proc. Amer. Acad. viii. 1870. 



Ponds or even on sandy banks; becoming scarce. 

 P. orieutale, L. Spec. 



Xeglected ground. Ames. 

 P. Persicaria, L. Spec. 



Damp places; common. 

 P. Hydropiper, L. Spec. 



Wet places ; common. 

 P. acre, HBK. Nov. Gen. & Sp. ii. 1817. 



Wet places : common. 



P. Virginianum, L. Spec. 



Woods: frequent. 



P. Convolvulus, L. Spec. 



Cultivated grounds, especially stubble; common. 

 P. dumetorum, L., var. scandens, (L.) Gray, Man. 5th ed.— P. 

 scandens. L. Spec. 



Thickets; common. 

 Fagopyrum esculentum, Moench, Meth. 1794. 



Cultivated ground ; frequent. 



