FLORA OF MICHIGAN. 127 



* 986. R. ACETOSELLA, L. Field or Sheep Sorrel. Th. 



Sterile fields. Common. 



987. K. ACETOSA, L. Sorrel Dock. U. P. 



Very abundant at Point-aux-Pins, above Sault de Ste. Marie, Maconn; N. shore of Lake Superior, 

 Pitcher, Trelease, Revision of Rumex. 



358. POLYGONTJM, Tourn. KNOTWEED. 



*988. P. aviculare, L. Th. 



The commonest of weeds. 



*989. P. erect mil, L. 



Waste places with the preceding species. Common. 



*990. P. tenue, Michx. 

 Sterile soil. S. Mich., Wright Cat.; common in Ionia Co.; Macomb Co., and northward. 



*991. P. lapathifolium, L. Th. 



River banks. Ionia Co.; Grand Rapids, Coleman Cat.; Keweenaw Co., F. Frequent. 



992. var. incaimm, Koch. 



Keweenaw Co., F. ; L. Superior, O. B. Wheeler. 



*993. P. Peimsylvanicum, L. C. & S. 



Low grounds. Ionia Co.; Clinton Co.; Flint; S. Mich., Wright Cat. Frequent. 



*994. P. ampliibium, L. Th. 



Borders of ponds. Frequent. 



*995. P. Mulilenbergii, Watson. 



E. shore Lake Huron, J. Macoun; Ionia Co.; Flint; Grand Rapids; Indian River; Black Lake; 

 Cheboygan Co. 



*996. P. Hartwrightii, Gray. Th. 



Kalamazoo, Tuthill; Indian River; Black Lake, Cheboygan Co., B. and K. ; Lenawee Co., 

 Dr. Beal; Keweenaw Co., F. 



997. P. ORIENTALE, L. Prince's Feather. 

 Sparingly escaped from gardens. 



*998. P. PERSICARIA, L. Lady's Thumb. Th. 



Waste places. Common. 



*999. P. hydropiperoicles, Michx. Mild Water-Pepper. C. & S. 



Wet places. Common. 



*1000. P. Hydropiper, L. Common Smartweed or Water-Pepper. Th. 



Moist grounds. Common. 



*1001. P. acre, HBK. Water Smartweed. L. P. 



Wet places. Ann Arbor; Ionia Co. ; Mackinac, Winch. Cat.; Flint. Frequent. 



1002. P. viviparum, L. U. P. 



Shore of L. Superior, Gray ; Isle Royale, common, Whitney Cat. 



*1(03. P. Virgrinianum, L. C.&S. 



Thickets. Common. 



1004. P. arifolium, L. Halberd-leaved Tear-thumb. L. P. 



Low grounds. South Haven, Bailey; IGros Cap, L. Mich. Winch. Cat.; S. Mich., Wright Cat. 

 Infrequent. 



*1005. P. sagittatum, L. Arrow-leaved Tear-thumb. Th. 



Low grounds. Frequent. 



{P. RAMOSISSIMUM, Michx. 



Should be looked for. as it is found on Manitoulin Islands, Can. Cat.] 



