SI'AKCANIACEAE (BUR-REED FAMILY) 



ear: polk-n Drains wimple. Reported from Denver; abundant on the Atlantic 

 also in Kurope and Asia. 



11. SPARGANIACEAE Agardh. BUR-REED FAMILY 



Rootstocks creeping and stoloniferous: roots fibrous. Stems simple or 

 I .ranching, >heathed below by the base of the linear leaves. Flowers collected 

 in .-eparate dense and spherical leafy-bracted heads, which are scattered along 

 the Hiinmit of the stem; the upper sterile, consisting merely of stamens, with 

 minute scales irregularly interposed; the lower or fertile larger, consisting of 

 numerous sessile 1-2-celled pistils, each surrounded by 3-6 scales much like a 

 calyx. Fruit wedge-shaped or club-shaped, more or less corky toward the 

 summit, the hard endocarp perforated at the apex. 



SPARGANIUM L. 



Characters of the family. 



Fruits sessile, angular 1. S. eurycarpum. 



Fruits stalked, terete or fusiform. 

 Emergent and erect. 



Inflorescence branched 2. S. androcladum. 



Inflorescence simple 3. S. simplex. 



Submersed or floating. 



Inflorescence branched 4. S. angustifolium. 



Inflorescence simple . . . . . . . . . 5. S. minimum. 



1. Sparganium eurycarpum Engelm. Gray, Man. Ed. 2. 430. 1856. Stems 

 stout, erect, 5-10 dm. high, with branched inflorescence: leaves mostly flat and 

 merely keeled : pistil attenuate into a short style bearing 2 elongated stigmas: 

 fruit heads 2-6 or more, 2-3 cm. broad: fruit many-angled, sessile, when 

 mature with a broad and depressed or retuse summit, abruptly tipped in the 

 center. Borders of ponds and streams; across the northern part of the United 



2. Sparganium androcladum (Engelm.) Morong, Bull Torr. Bot. Club 

 1 .") : 7s. 1 sss. Stems erect, slender, 3-5 dm. high, sparingly or freely branched: 

 pistillate heads 3-7, sessile or the lowest peduncled; style and stigmas 6 mm. 

 long: fruiting heads 12-25 mm. in diameter: fruits fusiform, 5-6 mm. long, 

 smooth or angled at the summit, often contracted in the middle; the stipe 3 

 mm. long. In bogs and shallow water; northeastern part of our range to 

 \e\v England. 



3. Sparganium simplex Huds. Fl. Angl. Ed. 2. 401. 1788. Stems slender, 



_'-4 dm. high: leaves more or less triquetrous: fertile heads (1-4) of the 

 usually simple inflorescence often above the axils, sessile or peduncled, 12- 

 1.") mm. wide in fruit: stigma linear, equaling the rather slender style, or 

 -h'.rter: nutlets pale, fusiform or narrowly oblong, about 4 mm. long, more or 



ntracted in the middle. Northern Wyoming and thence across the 

 continent . 



4. Sparganium angustifolium Michx. Fl. Bor. Am. 2: 189. 1803. Floating 

 in shallow or deep water: stems slender: leaves long and narrow, flat, with 

 -In aths often inflated at base: inflorescence 3-10 cm. long: staminate heads 



/>. Sparganium minimum Fries. Summa Veg. Skand. 2: 560. 1846. Usually 

 float in-, \\iih very slender stems and thin flat narrow leaves: fertile heads 1 or 

 '_'. axillary, sessile or peduncled, 8-10 mm. wide: stigma oval, about as long as 

 it style, scarcely sin passing the oval or obovate denticulate scales: 

 long-oborate, 2-4 mm. long, pointed, somewhat triangular, the stipe 

 Colorado to New England. 



