SEDGE FAMILY. 

 22. Scirpus atrovirens Muhl. Dark green Bulrush. 



Sii'-^iis at>-ovirens 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 

 green, 3 // -6 // wide, one or two of them usually ex- 

 ceeding the inflorescence; umbel i-2-compound or 

 simple; spikelets ovoid-oblong, acute, densely capi- 

 tate in 6's-2o'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; achcne 

 oblong-obovoid, 3-angled, pale brown, dull. 



In swamps, Nova Scotia to Manitoba, south to Geor- 

 gia and Louisiana. June-Aug. 



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 I'rt^l. Small- 

 fruited Bulrush. ji.) 



Scirpus microcarpus Pn-sl, Kc! H.u-nk I 19$. lijft. 

 Scirpus sylz-aticus var. <//>) Rorckl. Unmro & 



727. 1870. 



Perennial, the culms 3-5 tall, often Moot, 

 overtopped by the rough -margined leave*. I oan 

 leaves of the involucre usually exceeding the inflor- 

 escence; spikelets ovoid-oblong, acute, i>$ 

 long, 3-25 together in capitate cluster* at the cad* 

 of the usually spreading raylets; Kales brown with 

 a green midvein. blunt or subacute; bristles 4, 

 barbed downwardly nearly or quite to the base. 

 somewhat longer than the achene; stamen* 2; *tyle 

 2-cleft; achene oblong-obovate, nearly white, plano- 

 convex or with a low ridge on the back, pointed. 



In swamps and wet we*..: ^<ia to yticbrc 



and Alaska, south to Ni-w H.m. 

 York, Minnesota, Nevada and California Julr Srpt 



24. Scirpus polyphyllus Vahl. 



Set rpus polyphyllus Vahl, Enum. 2: 274. 1806. 



Perennial by slender rootstocks, culms slender, 

 sharply triangular, i)4-4 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 \y 2 " long, capitate in 3's-io'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. 



Leafy Hulrush. \ : \K. 632.) 



