308 T. Holm — Studies in the Gyperacem. 



structure of the perigyniuin. However, it is interesting to see 

 that some Scandinavian authors are inclined to consider G. 

 rufina as a reduced form of G. vulgaris. 



var. hydrophila nob. 



Rhizome very slender, stoloniferous, the scale-like leaves 

 persisting, shining, purplish brown ; leaves about as long as the 

 very slender culms, narrow but flat ; spikes cylindrical, dense- 

 flowered, peduncled, erect or somewhat spreading ; perigynium 

 prominently stipitate, roundish-elliptical, wholly glabrous and 

 nerveless. 



Yukon : in water, Colorado Creek, collected by Professor 

 John Macoun (No 53,843). 



var. lipocarpa nob. 



Rhizome densely csespitose with persisting, light brown 

 sheaths ; leaves glaucous, narrow but flat as long as the culms ; 

 culms from 15 to 40 cm in height, slender, but erect ; spikes long 

 and very dense-flowered except towards the base, more or less 

 peduncled, especially the lowest one, which is often developed 

 from near the base of the culm and branched ; bracts foliaceous 

 and quite long; perigynium with a long stipe, elliptical, gla- 

 brous, many-nerved, the beak very distinct and proportionately 

 long. 



Collected in Alaska at several stations, on Vancouver Island y 

 in the Selkirk Mountains, British Columbia, and in the Chilli- 

 wack Valley, by Mr. James M. Macoun and others. 



The fact that the perigynium is early deciduous in this 

 variety has led several authors to the belief that it is identical 

 with the South American G. decidua Boott, but the terminal 

 spike is, in this species, nearly always gy nsecandrous and the 

 perigynium is oblong-ovate, denticulate-serrate. 



Some of the specimens from Alaska were sent to Mr. C. B. 

 Clarke of Kew, who kindly informed the writer that these were 

 identical with Scouler's Columbia River plant, which Boott 

 first named G decidua, but afterwards corrected to G. vulga- 

 ris Fr. 



The so-called 0. interrupta Bcklr. var. impressa Bailey is, 

 also, according to Mr. Clarke, a form of G. vulgaris, and almost 

 like the typical plant. 



var. elatior Lang. 



Rhizome caespitose ; culms and leaves until 55 cm in length, 

 very slender ; spikes sessile, cylindrical and dense-flowered, some 



