572 CLX. CYPERACEiE. Eriophorum. 



11. S. BRUNNEUS. Muhl. 



>S'^. obtusely triangular, leafy, 2 — 3f high ; cyme decompound, its principal 

 branches about 5, unequal, with truncate sheaths at base ; spikelets 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 the achenium, tortuoits, 

 smoothish. Stem leafy. Umbel decompound. 



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



St. obtusely triangular, leafy, 3— 5f high ; Ivs. 2f long, rough-edged ; um- 

 bel terminal, decompound, large and loose ; spikes mostly pedicellate ; bristles 6, 

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

 achenium. — A common, stiff, 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 ; uvibels teraiinal 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. £piov, wool, ^epo), to bear; alluding to the copious bristles of the perigj-num. 



Glumes imbricated all around into a spike ; achenium invested in 

 very long, dense, woolly or cottony hairs. — Ste?n generally leafy. 

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

 * Spikelet solitary. 



1. E. ALPiNDM, 



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

 with 3 — 4 radical sheaths ; radical Ivs: 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 csespitose, 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—40 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. Dcnse-hcaded Eriophorum. 



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

 neled, rigid, triangular-subulate above, 8—12' long; sheaihs 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"), slightlv scabrous peduncles, 20—30- 

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

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

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

 and dense heads. 



4. E. POLYSTACHYUM. Mamj-splked Cotton Grass. 



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

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

 duncles which are long and drooping and sometimes branched ; seta 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. Narrmo-leaved Cotton Grass. 



St. 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 



