7S8 Order 155.— CYPERACE^E. 



narrowly linear, striate; Kheath close, truncate; spike oblong-ovate, 3 — 5" ia 

 length, 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- 

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

 fuscous. — Wet places N. Y. to I1L 



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

 3 — 6' higli ; spiko compressed, oblong-ovate, acute, 4 — 3-flowered ; glumes ob- 

 tusish, the lowest ono 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 S. piginaa Torr. Culm 1 — 2' high, setaceous, compressed., sulcata ; spikes 

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

 acheuium, slender, scabrous backwards; ach. ovale, 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-ftowered, about 2" long, often proliferous ; glumes ovate, 

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

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

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



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

 dense tufts ; spike minute, 1 to 2'' long, compressed, 4 to G-flmuercd ; glumes ovat% 

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

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

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

 cyperus Baldwinii Torr.) 



6. SCIR'PUS, L. Clue-rush. Bullrush. (Celtic cirs } the general 

 name for rushes.) Glumes imbricated on all sides ; perigynium of 3 — <J 

 bristles, persistent; sty. 2 — 3-eleft, not tubcrculate at base, deciduous; 

 achenium biconvex or triangular. — 21 Stems mostly triquetrous, simple, 

 rarely leafless. Spikes solitary, conglomerated or corymbous. 



I Scrapes. Bristles rctrorsely denticnlnte, about equaling the achenium. (*) 



* Spike single, terminal, with a short, erect bract at its base Nos. 1 — 8 



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



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



— on tho triangular culm Nos. 6—8 



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



b Glumes lacorately 3-toothed. Spikes large (0 to 12" lon<r) Nos. 9, TO 



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



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



§ Tmcopiiorum. Bristles C, tortuous, tawny, much longer than the achenium, and 

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



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

 angld, 5 — 10' high; lvs. broad-linear, flat, rough on tho margin, equaling the 

 stem; spike oblong-lanceolato, compressed, terminal, 4 — 8-fiowcred; glumes ovate- 

 mwcronate, yellowish ; bracts at the base of the spike, cuspidate, out*, r ones longer 

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

 In cold, hard soils, Mass. (Bobbins), N. Y. to Del. June. 



2 S. cubterminaiis Torr. Cidm floating, furrowed, inflated, leafy below, 1 to 3f 

 long ; lvs. very narrow, almost capillary, 2 to 4f long ; spike somewhat lermino) 

 (the stem being continued above -it in the form of a bract), lanceolate; style 2-ckft; 

 bristles 0. — Streams, &c, Mass. to K Y., Mich. Aug. 



3 S. ceespitostts L. Culm cmspitous, round, sheathed at base with numerous ru- 

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

 long as the spike ; ach. with G bristles. — Grows in dense tufts, 4 — 1 2' high. Spike 

 ■1 — 5-flowered, reddish-brown. On the alpine summits of Mts., N. Slates. Jl. 



4 S. debilis Pursh. Culm cajspitous, roundish, deeply striate, 9 to 1G' high, with 

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

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

 carinate, pale green ; ach. obovato, mucronato ; bristles 4 or 5. — Borders of ponds 

 and rivulets, ST. Bng. to Car. Aug. 



