740 Order 155.— CTPBRACB^ 



cattle do not eat, V. S. and Can. Aug. (Trioophoram cyp9rinum Pere.) 

 Variable. 

 15 S. line&tus Mx. Culm triangular, very leafy, 2 to 3f high ; umbels terminal 

 and axillary, decompound, at length nodding ; invol. 1 or 2 bracts, shorter tham 

 the umbels ; spikes ovoid, pedunculate, solitary ; glumes lancerflate, ferruginous ; 

 bristles 6, as long as the glumes, hardly exserted. — Swamps in most of the States. 

 Aug. (Tricophorum, Pers.) 



7. ERIOPH'ORUM, L. Cotton Grass. (Gr. epiov, wool, <j>ipo), to 

 bear ; alluding to the copious bristles of tbo perigyiiium.) Glumes im- 

 bricated all around into a spike ; achenium invested with many, rarely 

 only 6, very long, dense, woolly or coftony hairs. — Stem generally leafy. 

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



I Bristles of tho perigynium 6. Spike sing^lo No. 1 



I Bristles of the peiigynium numerous. — Spilie single No. 2 



— Spikes sevcmi. (*) 



* Spikes collected into a snbsessile, capitate cluster No. 8 



• Spikes separate, pedunculate, in urabellato clusters Nos. 4, B 



1 E. alpinum L. Culm very slender, acutely 3-angled, naked, somewhat sca- 

 brous, 8 — L6' high, with 3 — 4 radical sheaths; radical Ivs. very short, subulate; 

 spiko oblong, terminal, about 2" in length ; hairs 6 to each flower, woolly, white, 

 crisped, 4 times as long aa the- spike. — Bog meadows, often alpine, N. H. to N. 

 T. and Penn. JL 



2 E. vaginatum L. Sheathed Cotton Grass. Sts. densely oajspitous, 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 ; 

 liairs 30 — 40 to each flower, straight, white and glossy, twice as long as tho 

 spikelet, conspicuous, as well as in other species, even at a distance among the 

 meadow grass. — N. Eng. to Mich., N. to Arc. Am. Jn., JL 



3 E. Virgmicum L. Culm strict, firm, slender, tereteish, 2 to 3f high ; Iva 

 smooth, narrowly linear, shorter ; invol. 2 to 4-leaved, longer than the inflores- 

 cence ; spikes many, ovoid, acute, 3" long, glomerate, with very short peduncles, 

 forming a capitate cluster ; stam. 1, tawny, exserted with 3 tawny styles ; ache- 

 nium flattened, obovate, keeled on tho back, pointed, invested with '70 to 200 

 pale cinnamon colored setaj which are 4 to T' long. — Bogs, Can. and U. S. Jl., 

 Aug. In flower the heads are tawny red. 



8. CONFEETISSIMUM. Heads very large (20" diam.) and dense with white setae. 

 — In Northern N. H. (B. confertissimura Ed. 2d.) 



4 E. polystaohyon L. Culm somewhat triangular, smooth, 1 — 2f high ; cauliru 

 Ivs. 2 — 3, broad-linear, flattened below, triquetrous at tho end ; invol. 2-leaved ; 

 spikes about 10, on rough peduncles which are long and drooping and sometimes 

 branched; setaj 30 — 40 to each flower, white, 6 — 8" long, ach. obovate, obtuse. 

 — Very conspicuous in meadows and swamps, U. S. and Brit. Am. 



5 E. gracile Koch. Culm obtusely 3-angled, 18' to 2f high, roughish above; Ivs. 

 triquetrous, channeled on the upper side, scarce 1' wide ; invol, one-kaved, very 

 short ; ped. roughish or subpubescent, nodding ; spikes 3 to 8, ovoid, some sub- 

 sessile, others on peduncles 1 to 4" long ; glumes striate, brownish ; bristles 50 

 or more in each flower, 8 to 10" long, white ; ach. lance-obovatc, oljtuso. — 

 Bogs, N. States and Can. Common in N. J. (Jackson) (E. angustifolium Torr.). 



8. HEMICAR'PHA, Nees. (Gr. ijniavg, half, Kdp(pa, straw or chaff, 

 there being but one scale to the flower.) Spike man^'-flowercd ; glumes 

 imbricated all around ; interior scale 1, embracing the flower and fruit ; 

 bristles ; stamens 1 ; style 2-cleft, not bulbous at base, deciduous ; 

 achenium compressed, oblong, subterete. — If Low, tufted, with seta- 

 ceous culms and leaves. 



H. subsquarrosa Nees. Culm setaceous, compressed, sulcate, recurved, 2 — 3* 

 high; Ivs. setaceous, shorter than the scape; spikes 2 — 3, terminal (appa' 

 rently lateral), subsessile, ovoid, nearly 2" long ; invol. of 2 bracts, one appear- 



