524 
CYPERACEiE. (SEDGE FAMILY.) 
12. E* tricostata, Torr. Culms jlattish , thread-like (1°-2P 
high) ; spike cylindrical-oblong , densely many-flowered ; scales ovate, 
very obtuse, rusty brown with broad scarious margins; achenium ob- 
ovate with 3 prominent thickened angles , minutely rough-wrinkled , 
crowned with a short-conical acute tubercle ; bristles none. — Quaker 
Bridge, New Jersey, Knieskern , ex Torr. MSS. —Spike to | ; long, 
li" broad, somewhat pointed. 
Spike lanceolate-linear , scarcely broader than the sharply triangu¬ 
lar culm: scales Jew-ranked , greenish , finely several-nerved on the 
keeled back. 
13. E. Itobbilisii, Oakes. Flower-bearing culms exactly trian¬ 
gular , rather stout, erect (8 f - 2? high), also producing tufts of capillary 
abortive stems, like fine leaves, which float in the water; sheath ob¬ 
liquely truncate ; scales of the pointed spike 3-9, convolute-clasping, 
lanceolate, obtuse, with scarious margins ; achenium oblong-obovate, 
3-angular, minutely reticulated, about half the length of the 6 down¬ 
wardly-barbed strong bristles, tipped with a flattened awl-shaped tu¬ 
bercle.— Shallow water, from Pondicherry Pond, New Hampshire 
( Robbins ), to Rhode Island, Thurber , &c. Aug. — The spike of this 
singularly distinct species varies from to V long, by 1" wide; the 
long scales being rather remote and sheath-like. 
§ 3. Ch^tocyperus, Nees. — Scales of the compressed few-several- 
flowered spike membranaceous , 2 - 3- ranked : bristles 3 - 6, fragile or 
fugacious: style 3 -cleft: achenium triangular or somewhat terete: 
culms small and capillary. (Chactocyperus, Cyperoscirpus, and a 
part of Scirpidium, Torr. Cyp.) 
* Achenium obscurely triangular , many-ribbed on the sides. 
14. E. acidllaris, R. Brown. Culms finely capillary (2'- 
8 ' long), 4-angular; spike 3- 8-flowered; scales ovate-oblong, rather 
obtuse (greenish with purple sides); achenium obovate-oblong, rather 
acute at each end, tumid, with 3 ribbed angles and 2-3 times as many 
smaller intermediate ribs, also transversely striate, longer than the 3- 
4 very fugacious bristles; tubercle conical-triangular. (S. trichbdes, 
Muhl.y &c.) — Muddy places, and margins of brooks, common. June- 
August. 
* * Achenium triangular, icith plain smooth sides. 
15. E. pygm&a, Torr. Culms bristle-like, flattened and 
grooved (l f -2 / high); spike ovate , 3- 8-flowered; scales ovate (green¬ 
ish), the upper rather acute ; achenium ovoid, acutely triangula r j 
smooth and shining, tipped with a minute tubercle; bristles most) 
longer than the fruit, sometimes wanting. (S. pusillus, Vahi ? Chs* 
tocyperus polymorphus, JVecs ?) — Brackish marshes and river-banks, 
as far as salt water reaches. Aug., Sept. 
16. E. microcitrpa, var.? FiLictfLMis, Torr. “Culms capil¬ 
lary or thread-like, wiry, 4-angular (3'-4' high) ; spikes oblong , <>J ten 
