572 CLX. CYPERACEiE. Eriophorum. 



11. S. BRUNNEUS. Muhl. 



St. obtusely triangular, leafy, 2 — 3f high ; cyme decompound, its principal 

 branches about 5, unequal, with truncate sheaths at base ; spikelefs clustered in 

 heads of 3 — 6 ; glumes obtuse, reddish-brown ; ach. smooth, yellowish-white, 

 shorter than the 4 or 5 tortuous bristles. — Much resembles the last species. 

 Margins of waters, N. Eng. to Penn, W. to Ohio, rare. 

 § 2. Tricophorum. Bristles 6, much longer than theachenium, tortuous, 

 smoothish. Stem leafy. Umbel decompound. 



12. S. Eriophorum. Michx. (Tricophorum cyperinum. Pers.) 



St. obtusely triangular, leafy, 3 — 5f high ; lis. "2f long, rough-edged ; utw- 

 bel terminal, decompound, large and loose ; spikes mostly pedicellate ; bristles Q, 

 capillary, curled, very conspicuous, being 5 or 6 times as long as the white 

 achenium. — A common, stitf, rank meadow sedge, which cattle do not eat, U. S. 

 and Can. Spikes numerous, 2 — 3" long, ovoid, obtuse, in small clusters, in a 

 large, showy panicle. Involucre 4-leaved. Aug. 



13. S. LiNEATUS. Michx. (Tricophorum. Pers.) 



St. triangular, very leafy, 2 — 3f high ; umbels tenninal and axillary, de- 

 compound, at length nodding ; invol. of 1 — 2 bracts, longer than the leaves ; 

 spikes ovoid, pedunculate, solitary ; glumes lanceolate, ferruginous ; bristles 6, as 

 long as the glumes. — Swamps, in most of the States. Aug. 



8. ERIOPHORUM. 

 Gr. epiov, wool, 0£pa), to bear; alluding to the copious bristles of the perigynum. 



Glumes imbricated all around into a spike ; achenium invested in 

 very long, dense, woolly or cottony hairs. — Stem generally leafy. 

 Spikelets mostly in umbels. finally clothed with the long., silky hairs. 

 * Spikelet solitary. 



1. E. ALPiNUM. 



• St. very slender, acutel}'- 3-angled, naked, somewhat scabrous, 8 — 16' high, 

 with 3 — 4 radical sheaths; radical Zrs. very short, subulate ; spike oblong, ter- 

 minal, about 2" in length ; hairs 6 to each flower, woolly, white, crisped, 4 times 

 as long as the spike. — Bog meadows, often alpine, N. H. ! to N. Y. and Penn. Jl. 



2. E. VAGiNATUM. Sheathed Cotton Grass. 



Sts. densely caespitose, obtusely triangular, slender, smooth and rigid, 1 — 

 2f high ; uppermost sheaths inflated ; spikelet ovate, oblong, 6 — 8" long, of a 

 blackish color, with scarious glumes ; hairs 30 — ^10 to each flower, straight, 

 white and glossy, twice as long as the spikelet, conspicuous, as well as in other 

 species, even at a distance among the meadow grass. — N. Eng. to Mich., N. 

 to Arc. Am. June, July. 



♦ * Spikelets numerous. 



3. E. coNFERTissiMUM. Wood. Dense-hcadcd Eriophorum. 



St. strictly erect, firm but slender, 2 — 3f high ; Ivs. narrowly linear, chan- 

 neled, rigid, triangular-subulate above, 8 — 12' long; sheaths close; invol. 2- 

 leaved, one leaf twice, the other 4 — 5 times longer than the spikelets; spikelets 

 5 — 8, crowded, erect, on very short (2 — 4"), slightly scabrous peduncles, 20 — 30- 

 flowered ; glumes obovate, carinate, very obtuse ; ach. compressed, oblanceolate, 

 li" long, flat on one side, carinate on the other ; bristles 100 — 200, white, J' long, 

 straight and silky. — Bogs, Meriden, N. H. ! Distinguished for its very large 

 and dense heads. 



4. E. POLYSTACHYUM. Many-spUced Cotton Grnss. 



St. somewhat triangular, smooth, 1 — 2f high ; cauline Ivs. 2 — 3, broad- 

 linear, flattened below, triquetrous at the end ; spikelets about 10, on rough pe- 

 duncles which are long and drooping and sometimes branched ; setce 30 — 40 to 

 each flower, reddish-white, 6 — 8" long. — Very conspicuous in meadows and 

 swamps, U. S. and Brit. Am. 



5. E. ANGUSTiFOLiuM. Rich. Narroic-leaved Cottoii Grass. 



S<. slender, leafy, smooth, 10 — 15' high; cauline Ivs. narrow, 3-cornerecl, 

 with concave sides, 1 — 3' long ; invol. of one bract, with a loosely sheathing 



