^38 ORDER 155. CYPERACE^E. 



narrowly linear, striate; sheath close, truncate; spike oblong-ovate, 3 5" in 

 k'ngih, 20 30-flowered; glumes ovate-lanceolate, acute, mostly 2-cleft at apex, 

 dark purple on the back, with a broad, scarious margin ; bristles ; ach. obovate- 

 pvriforni. shining, minutely punctate, of a light, shining yellow, the minute tubercle 

 fuscous. Wet places N. Y. to 111. 



17 E. acicularis R. Br. Culm leafless, setaceous, quadrangular, very slender, 

 3 6' high ; spike compressed, oblong-ovate, acute, 4 8-flowered ; glumes ob- 

 tusish, the lo\vest one larger and empty; ach. obovoid, triangular, striated length- 

 wise. Edges of ponds, often partly submersed, U. S. and Brit. Am. Very deli- 

 cate. June, July. 



18 E. pigmeea Torr. Culm 1 2' high, setaceous, compressed, sulcato ; spikes 

 ovate, compressed, 3 6-fld. ; gl. mostly empty ; bristles 6, longer than the 

 achenium, slender, scabrous backwards; ach. ovate, acute, triangular, smooth, not 

 striate, whitish and shining ; tubercle minute. Sea coast, Mass., to Fla. and La. 



19 E. microcarpa Torr. Culm capillary, 4-angled, 5 to 8' long ; spike oblong, 

 compressed, 10 to 20- flowered, about 2" long, often proliferous; glumes ovate, 

 acutish, keeled, chestnut brown, the lowest much the largest, bristles 3 to 5, 

 shorter than the achenium which is minute, smooth, whitish, with a very minute 

 tubercle. "Wet places, N. J., also La. 



20 E. prolifera Torr. Culms capillary, 4-angled and furrowed, 4 to 12' long, in 

 dense tufts ; spike minute, 1 to 2'' long, compressed, 4 to ^-flowered ; glumes ovate, 

 chestnut brown, with scarious margins, often proliferous, that is, producing new 

 culms instead of flowers ; bristles 3 or 4, much shorter than the. achenium which 

 is 3-angled and with a broad, depressed tubercle. Fla. ! to La. (Hale). (Chseto- 

 cyperus Baldwinii Torr.) 



6. SCIR'PUS, L. CLUB-RUSH. BULLRUSH. (Celtic cirs, the general 

 name for rushes.) Glumes imbricated on all sides ; pcrigynium of 3 G 

 bristles, persistent ; sty. 2 3-clcft, not tuberculate at base, deciduous ; 

 achenium biconvex or triangular. It Stems mostly triquetrous, simple, 

 rarely leafless. Spikes solitary, conglomerated or corymbous. 



SCTRPUS. Bristles retrorsely denticulate, about equaling the achenium. (*) 



* Spike single, terminal, with a. short, erect bract at its base Nos. 1 3 



* Spikes several or many clustered on each culm, (a) 



a Clusters of spikes lateral on the terete, leafless culm * ...Nos. 4, 5 



on the triangular culm Nos. C S 



a Clusters of spikes terminal, mostly umbellate, (b) 



b Glumes laccrately 8-toothed. Spikes large (9 to 12" lonir) Nos. 9, 10 



b G kunes entire. Spikes small (I"), collected in globular heads Nos. 11, 12 



Spikes small (2 to 8" long), separate No. 13 



TUICOPFTOKTTM. Bristles C, tortuous, tawny, much longer than the acheuiutn, and 



exserted. Stem (culm) leafy. Umbel decompound Nos. 14, 15 



1 S. planifdlius Muhl. Culm ccespitous, leafy at base, acutely and roughly 3- 

 angfed, 5 10' high; Ivs. broad-linear, flat, rough ou the margin, equaling the 

 stem; spike oblong-lanceolate, compressed, terminal, 4 8-flowered; glumes ovate- 

 mucronate, yellowish ; bracts at the base of the spike, cuspidate, outer ones longer 

 than the spike ; ach. reddish-brown, invested with G bristles longer than itself. 

 In cold, hard soils, Mass. (Robbins), K Y. to Del. June. 



2 Q. cvibterminalis Torr. Culm floating, furrowed, inflated, leafy below, 1 to 3f 

 long; Ivs. very narrow, almost capillary, 2 to 4f long; spike somewhat terminal 

 (the stem being continued above it in the form of a bract), lanceolate ; s-tjle 2-cleft ; 

 bristles 6. Streams, &c., Mass, to K Y., Mich. Aug. 



3 S. csespitosus L. Culm ccespitous, round, sheathed at base wilh numerous ru- 

 diments of leaves; spikes compressed, terminal; 2 lower glumes involucre-like, aa 

 long as the spike; ach. with 6 bristles. Grows in dense tufts, 4 12' high. Spiko 

 4 5-flowered, reddish-brown. On tho alpine summits of Mts., N. States. Jl. 



4 B. debilis Pursh. Culm casspitous, roundish, deeply striate, 9 to 16' high, with 

 a few subulate leaves at base; spikeleis about 3, short-ovoid, sessile, crowded, 

 lateral, the culm continuing a fourth of its length above them, glumes ovate, obtuse, 

 carinate, pale green ; ach. obovate, mucronate ; bristles 4 or 5. Borders of ponds 

 and rivulets, N. Eng. to Car. Aug. 



