CYPERACE^E. (SEDGE FAMILY.) 565 



2. TRICH6PHORUM, Richard. Bristles capillary, naked, not barbed, elon- 

 gating, becoming tortuous and entangled, much longer than the triangular achenium, 

 when old mostly projecting beyond the rusty-colored scales : culm, leaves, frc. as in 

 the preceding subdivision ; umbel-like cymose panicle decompound. 



21. S. lineatUS, Michx. Culm triangular, leafy (l-3 high); leaves 

 linear, flat, rather broad, rough on the margins ; umbels terminal and some- 

 times axillary, loose, drooping, the terminal with a 1 - 3-leaved involucre much 

 shorter than the long and slender rays ; spikes oblong, becoming cylindrical 

 (2" -4" long), on thread-like drooping pedicels ; bristles at maturity scarcely 

 exceeding the ovate green-keeled and pointed scales; achenium sharp-pointed. 



Low grounds, W. New England to Wisconsin, and common southward. 



22. S. Eri6phorum, Michx. (WOOL-GRASS.) Culm nearly terete, very 

 leafy (2 -5 high) ; leaves narrowly linear, long, rigid, those of the involucre 

 3-5, longer than the decompound cymose-panicled umbel, the rays at length droop- 

 ing ; spikes exceedingly numerous, ovate, clustered, or the lateral ones pedi- 

 celled, woolly at maturity (l"-3" long) ; the rusty-colored bristles much longer 

 than the pointless scales ; achenium short-pointed. (Eridphorum cyperinum, L.) 



Var. CYPERINUS (S. cyperinus, Kunth) is the form with nearly all the spikes 

 conglomerate in small heads. Var. LAXUS (S. Eriophorum, Kunth) has the 

 heads scattered, the lateral ones long-pedicelled. Various intermediate forms 

 occur ; a"nd the umbel varies greatly in size. Wet meadows and swamps : 

 common northward and southward. 



9. EBIOPHOBUM, L. COTTON-GRASS. (PL 3.) 



Spikes, scales, achenium, &c. as in Scirpus. Bristles of the perianth of 

 numerous (in one species few) flat and delicate capillary bristles, which lengthen 

 greatly after flowering, much exceeding the scales, and forming of the capitate 

 spike a (white or reddish) conspicuous cotton-like tuft in fruit. Stamens 1-3. 

 Style 3-cleft. Perennials. (Name composed of e/atoi/, wool or cotton, and (popd, 

 bearing.) 



* Bristles of the flower only 6, crisped, white ; spike single : small, involucre none. 



1. E. alpinum, L. Culms slender, many in a row from a running root- 

 stock 6' -10' high), scabrous, naked; sheaths at the base awl-tipped. Cold 

 bogs, New England to Penn., Wisconsin, and northward. June. (Eu.) 



# * Bristles very numerous, not crisped, forming dense cottony heads in fruit. 

 * Culm bearing a single spike : involucre none. 



2. E. vaginatum, L. Culms in close tufts (1 high), leafy only at the 

 base, above with 2 inflated leafless sheaths ; root-leaves long and thread-form, 

 triangular-channelled ; scales of the ovate spike long-pointed, lead-color at 

 maturity. Cold and high peat-bogs, New England to mountains of Penn. 

 (Prof. T. Green), Wisconsin, and northward; rare. May, June. (Eu.) 



(E. RiissfcoLUM, Fries, with copper-colored wool, found in New Brunswick 

 by Rev. J. Fowler, may be expected in N. E. Maine.) 



i- *- Culm leafy, bearing several umbellate-clustered heads, involucrate. 



3. E. Virginicum, L. Culm rigid (2 -4 high) ; leaves very narrowly 

 linear, elongated, flat ; spikes nearly sessile, crowded in a dense cluster or head ; 



