PIPER FLORA OF THE STATE OF WASHINGTON. 231 



Specimens examined: Mount Rainier, Flett 305; Piper 2112; Mount Stuart, Elmer 

 1232, Brandegee 1066; Goat Mountain, Allen 127; Mount Adams, Henderson, August 9, 

 1892; SuJcsdorf, September, 1877; Flelt 1044. 



Zonal distribution: Arctic. 



This species was formerly confused with the more southern P. davisiae Brewer, and 

 appears under that name in Suksdorf's list. 



22. Polygonum phytolaccaefolium Mcisn.; Small, Bull. Torr. Club 19:360. 1892. 

 Type locality: California. 



Range: Washington and Idaho to California. 



Specimens examined: Mount Adams, Suksdorf 85; 10 miles north of Mount Adams, 

 Flett 1053. 



Zonal distribution: Hudsonian and Arctic. 



23. Polygonum alpinum foUosum (Keller) Small, Bull. Torr. Club 19: 360. 1892. 

 Pohjgonuin pohpnorjiliuni foViosurn Keller, Bull. Soc. Bot. Belg. 30: 49. 1891. 



Type locality: Mount Adams, Washington. 

 Range: Washington. 



Specimens examined: Mount Adams, SuJcsdorf 610 in 1885; Floirell d- Henderson in 

 1882. 



24. Polygonum hartwrightii A. Gray, Proc Am. Acad. 8: 294. 1870. 



Type locality: "Sedgy bogs, New York from Herkimer to Yates County, and 

 Michigan." 



Range: British Columbia and Saskatchewan, south to California, Kansas, and Maine. 



Specimens examined: White Salmon, Suksdorf 4S2; Coupeville, Gardner 254; Seattle, 

 Piper 720; Smith, July 11, 1889; Spokane, Dewart, June 6, 1901 ; Davis Lake, Kreager 438. 



Zonal distribution: Transition. 



25. Polygonum amphibium L. Sp. PI. 1: 361. 1753. 

 Type locality: Europe. 



Range: Alaska to Quebec, south to California, Colorado, and Pennsylvania. Europe, 

 Asia. 



Specimens examined: Seattle, Piper, August, 1892; Lake City, Fletl 170; Lake Wash- 

 ington, Piper, August, 1892; Wenache Mountains, Elmer 432; Lake ConconuUy, Whifed 

 1316; Pend Oreille River, Lyall in 1861 ; 6 miles east of Pullman, Piper, July 7, 1899; Lake 

 Kalispel, Kreager 338. 



Zonal distribution: Transition. 



26. Polygonum emersum (Michx.) Britton, Trans. N. Y. Acad. Sci. 8: 73. 1889. 

 Polygon)! m aniphibium eniersmn Michx. Fl. 1: 240. 1803. 



Polygonum muMenhergii Wats. Proc. Am. Acad. 14: 295. 1879. 



Polygonum amphibium terrestre Torr. Fl. U. S. 1: 403. 1824. 



Type locality: " Ad ripas fluminis Ohio. " 



Range: Biitsh Columbia to NewEngland, southward to Mexico, Louisiana, and Virginia. 



Specimens examined: Western Washington, latitude 49°, Lyall in 1858; Coulee City, 

 Lake & Hull 645; Rock Lake, Lake, August 3, 1893; Chelan, Elmer S.r-u ; junction Crab and 

 Wilson creeks, Sandherg d^ Leiherg 328; Union Flat, Lake cfc Hull 046; Pullman, Piper 1829; 

 Uriiontown, Henderson 2699 ; Prosser, Cotton 812. 



Zonal distribution: Arid Transition. 



Prof. E. L. Greene considers the Polygonum emersum, as generally understood to be an 

 aggregate of many species. Among these Elmer's 857 is made the type of Persicaria 

 chelanica Greene. o Some other segregates of this and related species, namely, Persicaria 

 cusickii Greene& and Persicaria oregana Greene c occur in Washington and adjoining States. 

 This group of species should receive much careful field study. 



a Leaflets 1: 49. 1904. b Op. cit. 42. c Op. cit. 31. 



