7° 



SPARGANIACEAE. 



Vol. I. 



Beaks gladiate-curved ; stigma short oblong. n. S. fluctuans. 



Stipe and beak of the achene short or none, always less than y 2 " long; fruiting heads about 5" 

 in diameter; stigmas oblong; anthers 1^-2 times as long as broad. 

 Heads all sessile, or the lowest short-pedicelled, axillary ; the staminate head distant from 



the pistillate ones; achenes short-beaked. 13- ■S'. minimum. 



Lower pistillate heads distinctly pedicelled and supra-axillary ; the staminate head close to 



the upper pistillate one. 12. S. hyperboreum. 



i. Sparganium eurycarpum Engelm. 

 Broad-fruited Bur-reed. Fig. 161. 



in A. Gray, 



Sparganium eurycarpum Engelm. 

 Man. Ed. 2, 430. 1856. 



Stem stout, 3°-8° high, branching. Leaves 

 linear, flat, slightly keeled beneath, the lowest 

 3°-5° long; staminate heads numerous; pistil- 

 late heads 2-4 on the stem or branches, sessile 

 or more commonly peduncled, hard, compact 

 and io"-i6" in diameter; style 1; stigmas 1-2; 

 nutlets sessile, z"s" ' on &» obtusely 4-5-angled, 

 narrowed at the base, the top rounded, flat- 

 tened or depressed, abruptly tipped with the 

 style; scales as long or nearly as long as the 

 fruit, often with 2 or 3 other exterior ones, 

 somewhat spatulate, the apex rounded, dentic- 

 ulate or eroded. 



In marshes and along streams, Newfoundland 

 to British Columbia, Florida, Missouri, Utah and 

 California. May-Aug. 



2. Sparganium androcladum ( Engelm. ) Morong. 

 Branching Bur-reed. Fig. 162. 



Sparganium simplex androcladum Engelm. ; A. Gray, Man. 



Ed. 5, 481. 1867. 

 Sparganium androcladum Morong, Bull. Torrey Club 15 : 



78. 1888. 

 Sparganium americanum androcladum Fernald & Eames, 



Rhodora 9 : 87. 1907. 



Stem branching, i°-3i° high; leaves ii°-3i° long, 

 triangular at the base; bracts similar to the leaves, 

 bases slightly dilated, and but narrowly scarious-mar- 

 gined; inflorescence branched; branches and peduncles 

 axillary, branches zigzag; fruiting heads 6"-i2" diam- 

 eter; nutlets brown, dull, fusiform, 2i"-3" long, terete 

 or obtusely angled, often constricted at the middle; 

 stigma linear, 1" long. 



In bogs or shallow water, Newfoundland to Minnesota, 

 Florida and Louisiana. June-Aug. 



3. Sparganium americanum Nutt. Nuttall's Bur- 

 reed. Fig. 163. 



Sparganium americanum Nutt. Gen. 2: 203. 181 8. 

 Sparganium simplex Nuttallii Engelm. : A. Gray, Man. Ed. 5, 

 481. 1867. 



Stem simple or nearly so, 1 °-2j° high; leaves i°-3i° long, 

 keeled, somewhat scarious-margined near the base; bracts, 

 at least the lower ones, similar to the leaves, but shorter, 

 dilated and scarious-margined near the base; inflorescence 

 usually simple, with the heads sessile, or the lower pistillate 

 ones peduncled, the branches, when present, straight ; fruit- 

 ing heads 9/-12" in diameter; nutlets brown, dull, fusiform, 

 2j"-3" long; stigma oblong, seldom over I" long. 



In low grounds or ponds, Nova Scotia and Ontario to Iowa, 

 South Carolina and Oklahoma. June-Aug. 



