348 CYPERACEiE. » Eleocharis. 



dull ; tubercle distinct, rostrate, slender. — Schult. mant. 2. p. 91 ; Torr. Cyp. p. 91 ; Kunth, 

 enum. 2. p. 141. Scirpus intermedius, Muhl. gram. p. 31 ; Torr. fl. \. p. 46. 



Culms very numerous, cespitose, mostly diffuse or recurved-prostrate, of a firm wiry texture, 

 conspicuously sulcate and somewhat angular, pale green. Sheaths cuspidate. Spike about 2 

 lines long, rather acute. Scales membranaceous, not scarious on the margin : margin narrow 

 and green ; the sides reddish brown. Bristles 6, strong, whitish, retrorsely hispid, a little 

 overtopping the tubercle. Stamens 3. Achenium hght brown, very finely striated longitudinal- 

 ly, remarkably attenuated at the base. Tubercle quite free around the base, very slender 

 and acute. 



Wet places, particularly in shallow running water : frequent in the northern and western 

 parts of the State. Fl. July. Fr. August - September. 



6. Eleocharis obtusa, Schultes. Obtuse-headed Spike-rush. 



Culm terete or slightly compressed, spongy ; spike globose-ovoid or globose- oblong, many- 

 flowered ; scales very obtuse ; bristles longer than the achenium ; style 3-cleft ; achenium 

 obovate, lenticular, margined, smooth and shining ; tubercle much dilated at the base, rather 

 acute, compressed. — Schult. mant. 2. p. 89 ; Torr. Cyp. p. 302; Kunth, enum. 2. p. 152. 

 Scirpus obtusus, Willd. enum. hort. Berol. I. p. 76 ; Roem. ^ Schult. syst. 2. p. 1 26 ; Dar- 

 lingt. fl. Cest. p. 19. S. capitatus, Walt. fl. Car. p. 70 ; Pursh, fl. I. p. 55 ; Ell. sk. 1. 

 p. 77 ; Muhl. gram. p. 30 ; Torr. fl. 1. p. 4^5; Bigel. fl. Bast. p. 20 ; Beck, hot. p. 424. 

 S. ovatus, Pursh, I. c; Muhl. cat. p. 6. 



Culms cespitose, 8-15 inches high, erect, contracted immediately below the spike, soft 

 and spongy, clothed at the base with one or more purplish truncate sheaths. Spike thick and 

 obtuse, 50 - 80-flowered, often nearly globose, and sometimes elongated so as to be nearly 

 cylindrical. Scales membranaceous, with a scarious margin and green midrib. Bristles 6, 

 stout and rigid, retrorsely hispid, nearly twice as long as the nut. Stamens 3. Achenium 

 doubly convex, light brown ; the margin tumid. Tubercle somewhat axe-form (the breadth 

 greater than the length), with a short obtuse-angled summit. 



Bogs, and muddy borders of ponds and rivers : common. Fl. June - July. Fr. August. 



*♦ MiTROCARPA, Torr. Spike ovoid; the scales coriaceous. Bristles 6, rigid. Achenium obtusely triangular. Tubercle 

 mitriform, spongy, nearly as large as the achenium. Style 3-ckfl. 



6. Eleocharis tuberculosa, R. Br. Large-tuhercled Spike-rush. 



Culm terete, filiform, striate ; spike globose-ovoid, somewhat acute ; scales broadly ovate, 

 very obtuse, loose, coriaceous ; achenium oblong, striate and pitted longitudinally ; tubercle 

 ovoid, obtuse, nearly as large as the achenium. — R. Br. prodr. 1. p. 224 (in ohs.) ; Ram, 

 4" Schult. syst. p. 152 ; Torr. Cyp. p. 307 ; Kunth, enum. 2. p. 145. Scirpus tuberculosus, 

 Michx. fl. 1. p. 30; Pursh, fl. 1. p. 54:] Beck, hot. p. 424. S. tuberculatus, Ell. sk. 1. 

 p. 78. 



