Eleocharis. CYPERACE^E. 221 



usually 3-cleft, the conical or flattened tuberculate base persistent and mostly jointed 

 upon the summit of the turgid- triangular or lenticular nutlet. Stems tufted, from 

 matted or creeping rootstocks, terete or angular, the base covered with closely 

 appressed sheaths. Lower scale of the spikelet sometimes enlarged and bract-like. 



A genus of nearly a hundred species, distributed over the tropical and temperate regions of the 

 globe, a few even arctic. Twenty species or more are found in North America. The genus is re- 

 ferred by some authorities to Scirpus, and on the other hand is divided into several by Nees and 

 others. 



* Spike small and few-flowered, the scales somewhat distichous or only ^-ranked: 

 style 3-cleft and nutlet triangular. Low and slender. 



t- Tubercle contracted at its junction with the nutlet. 



1. E. acicularis, R. Br. Stems tufted, with fibrous roots and very slender 

 running rootstocks, usually setaceous, 1 to 8 inches high : spike 3 - 9-flowered, 1 to 

 3 lines long ; scales ovate-oblong, acutish, | to 1 line long, more or less deeply 

 tinged with brown : bristles 3 or 4, often wanting : nutlet oblong-obovate, obscurely 

 triangular and faintly ribbed on the sides, half a line long ; tubercle broad, short 

 and blunt. Scirpus acicularis, Linn. ; Reichenb. Icon. Fl. Germ, viii, t. 294. 



A common species, on sandy or muddy stream-banks, from Santa Barbara (Rothrock) to British 

 Columbia (Lyatl), and across the continent ; also in Mexico, and in Europe and Asia. 



2. E. pygmaea, Torr. Stems an inch or rarely 2 to 4 inches high, flattened 

 and grooved : spike 2 - 4-flowered, rarely more, greenish, the lowest scales usually 

 somewhat the largest : bristles often wanting : nutlet obovate, acutely triangular, 

 smooth and shining. Gyp. 313, and Pacif. R. Rep. iv. 152. 



Near Cocomungo (Bigelow], as referred by Dr. Torrey, though the specimens are too young for 

 positive determination. The species is found in brackish marshes in the Atlantic States and 

 westward to New Mexico. Boeckeler refers it to the European Scirpus parvulus. 



i *- Tubercle continuous with the nutlet and not contracted at base. 



3. E. pauciflora. Stems tufted, erect, from slender running rootstocks, 3 to 

 8 inches high, striate : spike ovate-oblong, 2 or 3 lines long, the dark brown oblong 

 acute scales nearly 2 lines long : bristles 3 to 6, usually equalling the nutlet : fila- 

 ments and stigmas long-exserted : nutlet oblong-obovate, obtusely triangular, a line 

 long excluding the rather stout pyramidal tubercle, which is nearly a third as long 

 as the nutlet. Scirpus pauciflorus, Lightf. ; Reichenb. 1. c., t. 299 ; Gray, Manual, 

 560. 



Soda Springs, head of Tuolumne River (Brewer) ; Klamath Valley (Gabb, Kronkhite) ; Wyo- 

 ming and Colorado, and in the northern Atlantic States ; also in Europe and Asia. The species 

 has usually been included under Scirpus, but there appears to be no good reason for separating it 

 from E'cocharis, inasmuch as it has all of the characters which distinguish that genus from Scir- 

 pus. The tubercle is identical in character with that of E. rostfUat.ua and its allies, and such as 

 is not found in Scirpus, where the style is slender and never tubercle-like at base. 



* * Spike terete, many-flowered. 



t Tubercle somewhat contracted at its junction with the nutlet. 

 H- Style 2-cleft and nutlet lenticular. 



4. E. palustris, R. Br. Stems usually slender, from running rootstocks, terete, 

 striate, | to 4 (usually 1 or 2) feet high : spike oblong-lanceolate to linear, acute, 3 

 to 1 2 lines long ; scales ovate-oblong or the lowest ovate, obtuse or the upper 

 acutish, thin, brown with white margin and greenish keel : bristles 4, about equal- 

 ling the obovate turgid smooth nutlet, which is a line long including the broad- 

 deltoid acutish or acute, rarely acuminate tubercle. Scirpus palustris, Reichenb. 

 1. c., t. 297. 



Very common in water or wet grounds and very widely distributed, being found throughout 

 the United States and British America, and in most parts of the Old World. 



