788 ORDER 1 55. CYPERACE^B. 



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

 length, 20 30-flowered - f 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, tho minute tuberelo 

 fuscous. Wet places K Y. to IU. 



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 lowest 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 B. pigm^a Torr. Culm 12' high, setaceous, compressed, sulcate ; 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 B. microcarpa Torr. Culm capillary, 4-angled, 5 to 8' long; spike obloug, 

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

 acutish, keeled, chestnut brown, tho 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, \io f L 1 ' long, compressed, 4 to 6-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. CLUE-RUSH. BULLRUSH. (Celtic cirs, the general 

 name for rushes.) Glumes imbricated on all sides ; perigynium of 3 6 

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

 achcnium biconvex or triangular. 2 Stems mostly triquetrous, simple, 

 rarely leafless. Spikes solitary, conglomerated or corymbous. 



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



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



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



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



on the triangular culm Nos. 68 



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



b Glumes lacerately 8-toothed. Spikes larse (9 to 12" loni:) Nos. 9, 10 



b Glumes entire. Spikes small (1"), collected in globular heads Nos. 11, 12 



Spikes small (2 to 3" long), separate No. 18 



TBICOPIIORUM. Bristles (5, 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- 

 angkd, 5 10' high; Ivs. broad-linear, flat, rough on tho 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), N. Y. to Del. June. 



2 S. subterminalis Torr. Culm floating, furrowed, inflated, leafy below, 1 to 3f 

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

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

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



3 S. caespitosus L. Culm caispitous, 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 6 bristles. Grows in dense tufts, 412' high. Spike 

 4 5-ilowered, reddish-brown. On the alpino summits of Mts., N. States. Jl. 



4 S. d6bilis Pursh. Culm csespitous, roundish, deeply striate, 9 to 16' 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. obovate, mucronate ; bristles 4 or 5. Borders of ponda 

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



