266 CYPERACEAE. 
13. Scirpus mucronatus L. Bog Bulrush. 
(Fig. 621.) 
Scirpus mucronatus L,. Sp. Pl. 50. 1753- 
Perennial, culms stout, somewhat tufted, sharply 
3-angled, smooth, 1°-3° tall. Spikelets 5-12 in a 
capitate cluster, oblong, obtuse, many-flowered, 
4/’-9’’ long, rather more than 1’ in diameter, sub- 
tended by the solitary linear abruptly spreading in- 
volucral leaf; scales broadly ovate, obtuse, light 
brown with a narrow green midvein, mucronate; 
bristles 6, stout, rigid, downwardly barbed, as long 
as the achene; stamens 3; style 3-cleft; achene ob- 
ovoid, smooth, shining, dark brown, 3-angled, two 
of the sides narrower and more convex than the 
third. 
In a swamp in Delaware county, Pennsylvania. 
Probably adventive or fugitive from Europe. Widely 
| distributed in the Old World. July-Sept. 
14. Scirpus cylindricus (Torr.) Britton. Canby’s Bulrush. (Fig. 622.) 
Scirpus maritimus var. cylindricus Torr. Ann, 
Lyc. N. Y. 3: 325. © 1836. 
Scirpus leplolepis Chapm. F1. S. States, 520. _ 1860. 
Scirpus Canbyi A. Gray, Am. Journ. Sci. (II.) 38: 
289. 1864. 
Scirpus cylindricus Britton, Trans. N. Y. Acad. Sci. 
II: 79. 1892. 
Perennial by stout rootstocks, culm stout, 
sharply 3-angled above, 3°-6° high, the linear 
nodulose keeled and channeled dark green 
leaves nearly or quite as long. Involucral leaf 
solitary, 4/-10’ long, erect; spikelets in an appa- 
rently lateral simple or compound umbel, droop- 
ing, oblong-cylindric, acutish, 6’’-10’’ long; 
primary rays of the umbel 1’-4/ long, bracted 
by 1 or more subulate-linear leaves; scales ovate 
or oyate-lanceolate, pale brown with scarious 
margins, acute, mucronulate; bristles 6, stout, 
rigid, about as long as the achene, serrate; sta- 
mens 3; style 3-cleft; achene obovoid, 3-angled, 
light brown, smooth, abruptly subulate-pointed. ee } 
In ponds and swamps, Maryland to Florida and Louisiana, mostly near the coast. July-Sept. 
15. Scirpus lacistris I. Great Bulrush. Mat-rush. (Fig. 623.) 
Scirpus lacustris I,. Sp. Pl. 48. 1753. 
Scirpus validus Vahl, Enum. 2: 268. 1806. 
Perennial by stout rootstocks, culm stout, terete, 
smooth, erect, 3°-9° tall, sometimes nearly 1’ in di- 
ameter, sheathed below, the upper sheath occasion- 
ally extended into a short leaf. Involucral leaf soli- 
tary, erect, shorter than the umbel, appearing as if 
continuing the culm; umbel compound, appearing 
lateral, its primary rays slender, spreading, 1/—4/ 
long, bracts linear-lanceolate, scarious; spikelets ob- 
long-conic, becoming oblong-cylindric, sessile or some 
of them peduncled, in capitate clusters of 1-5, obtuse 
or acute, 2%4’/-8’” long, 11%4’/-2’’ in diameter; scales 
ovate or oblong, with a rather strong midvein which 
is sometimes excurrent into a short tip; bristles 4-6, 
downwardly barbed, equalling or longer than the 
achene ; stamens 3; style 2-cleft; achene plano-con- 
vex, obovate, gray, abruptly mucronate, dull. 
\ 
In ponds and swamps, throughout North America. Also in the Old World. June-Sept 
