346 CYPERACEiE. Eleocharis. 



Tribe III. SCIRPE^. Nees ; Torr. 



Flowers perfect. Scales of the spike imbricated on all sides {rarely, by the torsion of the 

 rachilla, bi-trifarious). Perigynium consisting of several {mostly 6) bristles, hairs or 

 linear scales ; sometimes wanting. > 



• With a perigynium. 



4. ELEOCHARIS. R. Br. prodr. 1. p. 224 ; Torr. Cyp. p. 296. SPIKE-RUSB. 



[ Prom the Greek, elos, eleos, a marsh, and chairo, to delight j from the place of growth.] 



Scales of the spike imbricated on all sides, or sometimes imperfectly bifarious. Bristles of 

 the perigynium 3-12 (commonly 6, rarely wanting), rigid and persistent, usually rough 

 or hispid. Style 2 - 3-cleft ; the base bulbous and persistent, articulated to the ovary. 

 Achenium either lenticular or obtusely triangular, crowned with the bulbous base of the 

 style or tubercle. — Culms simple, leafless, with truncate or mucronate sheaths at the base : 

 spike terminal, solitary, naked. 



 Eleocharis proper. Spike ovate or oblong : scales membranaceous (rarely coriaceous), very numerous, irregutarly 

 imbricated. Style mostly %deft. Aclienium obovoid, bieonvex, smooth : tubercU somewhat corky. 



1. Eleocharis palustris, R. Brown. Common Spike-rush. 



Culm terete, striate, spongy ; spike oblong-lanceolate ; scales somewhat obtuse , the two 

 lowest large, orbicular and empty ; bristles hispid, longer than the achenium ; style 2-cleft ; 

 nut lenticular, smooth (fulvous) ; tubercle conical-rostrate, acute, distinct. — R. Br. prodr. 1. 

 p. 224 (in obs.); Smith, Engl. fl. 1. p. 63 ; Torr. Cyp. p. 299 ; Kunth, enum. 2. p. 147. 

 Scirpus palustris, Linn. sp. 1. p. 47 ; Pursh, fl. 1. p. 54 ; Ell. sk. 1. p. 77 ; Muhl. gram, 

 p. 28 ; Torr. fl. 1. p. 45 ; Bigel. fl. Bost. p. 20 ; Beck, bot. p. 425 ; Darlingt. fl. Cest. 

 p. 19. S. glaucus, Torr. fl. I. p. 44. 



Rhizoma creeping. Culm erect, 1-2 feet high, of a soft texture, varying in diameter from 

 filiform to a line and a half. Spike 3-6 lines long, many-flowered. Scales fuscous in the 

 middle, with a broad scarious and generally lacerated margin. Bristles 3-6, overtopping 

 the tubercle, retrorsely hispid. Stamens 3. Achenium compressed, smooth but dull. Tubercle 

 rostrate-conical, acute, nearly half the length of the achenium, which is contracted into a short 

 neck beneath it. 



Swamps and low grounds ; the taller and stouter forms growing in water, but sometimes in 

 sand along the shores of rivers and lakes. Fl. August. Fr. September. I have specimens 

 of an Eleocharis from the western part of the State, which resembles E. palustris in many 

 respects ; but there are no bristles surrounding the achenium, and the tubercle is very short. 

 It grows from 3 to 10 inches high ; the culm slender and nearly terete : the spikes are ovoid- 

 conical. It may be regarded as a provisional species, under the name of E. calva. 



