196 METCALF: NOTES ON NORTH DAKOTA PLANTS 



Salix tristis Allioni. Very rare, found only in Sand Hills, near Lake 

 George, Drake, McHenr3'' Co. (No. 416, Aug. 28, 1917, D. C. Mabbott). 

 This extends the range of this plant westward as previously the farthest 

 westerly record was that of Bergman, namely, Hankinson, Richland Co. 



Rimiex Brittannica Linnaeus. Not previously reported from the 

 state. Range extended westward as manuals give Minnesota-Kansas as 

 the western limit of distribution. Collected only from border of Camp 

 Lake, McLean Co. (No. 416, Sept. i, 191 7). 



Polygonum amphibium Linnaeus. Rather rare, reported with the 

 exception of Emmons County, only from the more northern counties — 

 Ward, Ramsey, Rolette, Towner, Burke and known from but one lake 

 in each of these. Another form of this species masquerading under the 

 name P. amphibium Linnaeus Var. Hartwrightii (Gray) Bissel, was rare, 

 only reported from partially dried out mud flats of Section 13-14, 

 Frettin Lake, Kidder County and L'psilon Lake, Rolette County. 

 Still another form of this same species known as P. Muhlenbergia 

 (Meisner) Watson was common throughout the state growing in water 

 and in moist meadows bordering fresh water lakes. These so-called 

 species can only be considered forms of P. amphibium; this species is 

 very variable, all forms intergrading one into the other, depending on 

 ecological conditions. Poole has written as follows:^ "The development 

 of the hvdro-mesophytic mode of life by these species is a fact of every-day 

 observation. In the marshy areas of the sandhills one can trace a per- 

 fect series of changes from the typical form called P. amphibium through 

 P. Hartwrightii and finally to P. emersum {Muhlenbergia). The first 

 two forms, though often very different appearing plants, may commonly 

 be collected from the same rhizome. The latter species is almost as 

 variable and it seems a plain case that these three 'species' are merely 

 extreme variations that may be found arising from the same rootstock," 

 a fact verified by the author in North Dakota. To continue to give 

 distinct rank to these forms as is done in Britton and Brown's "Illus- 

 trated Flora" and Gray's "7th Edition Manual" is a mistake. 



Chenopodium humile Hooker. Not previously reported from the 

 state but possibly included rightfully within the species C. rubrum. 

 On the shores of Middle Des Lac Lake, Ward Co. (No. 561, Oct. i, 

 1 91 7) were a few plants that were clearly C. humile Hooker but along 

 with these were a number of forms that represent intermediate steps 

 between the two species, showing that C. humile was in all probability 

 onlv a form grooving under unfavorable conditions. 



Suaeda linearis (Elliott) Moquin-Tandon. Not previously recorded 

 from the state. Range extended greatly westward as apparently no 

 i aland stations are known for this plant. Found along border of 

 stro- gly saline lakes — Holmes Lake, McLean Co. (No. 466a, Sept. 5, 

 1917) and Minto Lake, Walsh Co. (No. 511, Sept. 21, 1917, D. C. Mab- 

 i ott). 



Spergularia marina (Linnaeus) Grisebach. Frequent throughout 

 the state, recorded from Cushion Slough, Burke Co. (No. 583, Oct. 3, 



* Poole, Raymond I. A study of the vegetation of the sandhills of Nebraska, p. 287. 



