‘green, 3//-6’ wide, one or two of them usually ex- 
_ gia and Louisiana. June—Aug. 
: Scirpus polyphyllus Vahl, Enum. 2: 274. 1806. 
SEDGE FAMILY. 269 
22. Scirpus atrovirens Muhl. Dark green Bulrush. (Fig. 630.) 
Scirpus atrovirens Muhl. Gram. 43. 1817. 
Perennial by slender rootstocks, culms triangu- 
lar, rather slender, leafy, 2°-4° high. Leaves 
elongated, nodulose, rough on the margins, dark 
Jf 
ceeding the inflorescence; umbel 1-2-compound or 
simple; spikelets ovoid-oblong, acute, densely capi- 
tate in 6’s-20’s at the ends of the rays or raylets; 
involucels short; scales greenish-brown, oblong, 
acute, the midvein excurrent; bristles usually 6, 
downwardly barbed above, naked below, about as 
long as the achene; stamens 3; style 3-cleft; achene 
oblong-obovoid, 3-angled, pale brown, dull. 
In swamps, Nova Scotia to Manitoba, south to Geor- 
Scirpus atrovirens pallidus Britton, Trans. N. Y. Acad. 
Sci. 9:14. 1889. 
Whole plant pale green; scales awned; spikelets ob- 
long-cylindric, very numerous in the capitate clusters. 
Minnesota to the Northwest Territory and Colorado. 
23. Scirpus microcarpus Presl. Small- 
fruited Bulrush. (Fig. 631.) 
Scirpus microcarpus Presi, Rel. Haenk. 1: 195. 1828. 
Scirpus sylvaticus var. digynus Boeck]. Linnaea, 36: 
727. 1870. 
Perennial, the culms 3°-5° tall, often stout, 
overtopped by the rough-margined leaves. Longer 
leaves of the involucre usually exceeding the inflor- 
escence; spikelets ovoid-oblong, acute, 114/’/-2// 
long, 3-25 together in capitate clusters at the ends 
of the usually spreading raylets; scales brown with 
a green midvein, blunt or subacute; bristles 4, 
barbed downwardly nearly or quite to the base, 
somewhat longer than the achene; stamens 2; style 
2-cleft; achene oblong-obovate, nearly white, plano- 
conyex or with a low ridge on the back, pointed. 
In swamps and wet woods, Nova Scotia to Quebec 
and Alaska, south to New Hampshire, northern New 
York, Minnesota, Nevada and California. July-Sept. 
24. Scirpus polyphyllus Vahl. Leafy Bulrush. (Fig. 632.) 
Perennial by slender rootstocks, culms slender, 
sharply triangular, 144°-4° tall, very leafy, the 
leaves 2//-3/’ wide, exactly 3-ranked, inconspicu- 
ously nodulose, rough-margined, the upper rarely 
overtopping the culm; leaves of the involucre 3-6, 
the longer commonly somewhat exceeding the in- 
florescence; umbel more or less compound; spike- 
lets ovoid, about 1%’’ long, capitate in 3’s-10’s at 
the ends of the raylets; scales ovate, bright brown, 
mostly obtuse, mucronulate; bristles 6, flexuous or 
twice bent, downwardly barbed above the middle, 
twice as long as the achene; stamens 3; style 3- 
cleft; achene obovoid, 3-angled with a broad face 
and narrower sides, short-pointed, dull. 
In swamps, wet woods and meadows, Massachusetts 
to Minnesota, south to Alabama and Arkansas. Some 
of the scales of the spikelets occasionally develop into 
linear leaves. July—Sept. 
