1922] Fernald,—Notes on Sparganium 29 
S. cHLoRocARPUM Rydberg, var. acaule (Beeby), n. comb. S. 
simplex, var. acaule Beeby in Macoun, Cat. Can. Pl. ii. 367 (1890). 
S. diversifolium, var. acaule Fernald & Eames, RHODORA, ix. 88 (1907). 
S. acaule Rydberg, N. A. Fl. xvii. 8 (1909). 
When the erect Sparganium of northeastern America with supra- 
axillary heads and short stigma (0.8-1.7 mm. long) was separated 
in 1907 from the Eurasian and western American S. simplex Hudson, 
a plant with larger fruits and longer stigma, it was identified with 
with S. diversifolium Graebn. This identification was due to the fact 
that in the Pflanzenre’ ^ rraebner cites, besides the typical European 
material of S. diversifu..wm, Newfoundland, New England and Min- 
nesota specimens of the common American plant. Subsequently 
Rydberg has described the larger extreme of the American plant as 
S. chlorocarpum! and has proposed as another species the smaller 
extreme, var. acaule. 'That the American plants should not be 
placed with S. diversifolium now seems clear. In discussing Graeb- 
ner's species in 1912, Dr. Rothert said in a letter: 
“T am much interested to learn from your letter, that S. chloro- 
carpum Rydb. is a form of S. diversifolium (in your sense) 
I agree with you that the smaller and the larger form of S. TRO 
ium are clearly different in typical specimens . . . . Loriginally 
supposed them to be 2 distinct species; yet they are linked together 
by so many and various transitions, that I am quite unable to trace 
a limit between them, even as varieties. 
* As to the nomenclature of this species, I think that the name S. 
diversifolium Graebner can by no means be kept. Graebner's name 
comprises chiefly S. simplex x minimum and slender forms of S. simplex; 
besides, I have seen specimens of S. affine, S. minimum, S. glomeratum 
and S. affine x minimum determined by G. himself as S. diversifol- 
ium, not a single one of all these fitting his description. I think a 
name so extremely indefinite must be absolutely cancelled and the 
species considered as fantastic." 
In the figures accompanying Graebner's original publication of S. 
diversifolium? the sepals are shown to be broadly obovate and narrowed 
to a slender claw. In our American plant the sepals are narrowly 
cuneate-spatulate and without definite claw. The name S. diversi- 
folium should, therefore, drop from our American floras. 
1Rydb. N. A. Fl. xvii. 8 (1909). 
? Graebner, Schrift. Naturf. Gesellsch. Danzig, n. f. ix. 335, t. 8, fig. 1b. (1895). 
