573 CLX. CYPERACE^. Eriophorum, 



11. S. BRUNNKUS. Muhl. 



5"'. obtusely triangular, leafy, 2 — 3f high ; cyme decompound, its principal 

 branches about 5, unequal, with truncate sheaths at base; spikckts 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. Tricophordm. Bristles 6, much longer than theachenium, tortuous, 

 smoothish. Stem leafy. Umbel decompound. 



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



SI. obtusely triangular, leafy, 3 — 5f high ; lis. 21 long, rough-edged ; nm- 

 hcl 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. LiNEATCs. Michx. (Tricophorum. Pcrs.) 



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

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

 spikes ovoid, pedunculate, solitar}-; glumes lanceolate, ferruginous; bi-isths 6. as 

 long as the glumes. — Sv/amps, in most of the States. Aug. 



8. ERIOPHORUM. 



Gr. epiop, wool. (}>£po), to bear; alluding to the copious bristles of the perigjiium. 



Glumes imbricated all around into a spike ; aclienium invested in 

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

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

 * Spikelet solitary. 



1. E. ALPiNUM. 



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

 with 3 — 4 radical sheaths; radical Zr5. 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. VAGixATUM. Sheathed Cotton Grass. 



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

 2f high; v.ppcrmost s/icaths inflated; spikelet ovate, oblong, 6 — 8" long, of a 

 blackish color, w^ith scarious glumes ; hairs 30 — 40 to each flower, straight, 

 white and glos.sy, 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. DcHse-hcaded Eriaphorum. 



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- 

 flowcred ; glumes obovate, carinate, ver)' obtuse ; ach. compressed, oblanceolate, 

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

 straight and silky. — Bogs, Meriden, N. H. 1 Distinguished for its very large 

 and dense heads. 



4. E. POLYSTACHYUM. Mamj-spiked Cotton Gr<iss. 



St. somewhat triangular, smooth, I — 2f high ; caxdine 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; sctcB 30—40 to 

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

 swamps, U. S. and Brit. Am. 



5. E. ANGUsriFOr.iu.M. Rich. Narrow-leaved Cotton Grass. 

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



with a loosely sheathing 



