310 



UKDK1J CXXXIX. fYJ'KK.N 



axillary peduncles. Glumes arranged in 2 rows. Perianth 

 1 to bristles surrounding the ovary. Stamens 3. Styl,< 

 2-cleft above, the lower portion persistent, forming a beak I" tli<> 

 compressed achenium. 



1. D. spathaceum. Sheathed Sedi/c. 



Culm tract, simple, leafy through the whole length, sheathed below ; leaves 

 alternate, linear, flat, short, arranged on the stem In 8 rows ; spikes axlll ary and 

 terminal, proceeding from the sheaths, consisting of 8 12 linear-lanceolate 

 spikelets, loosely arranged In 9 rows; splkelets 69 flowered, rather long. A 

 common plant along rivers and borders of ponds, 13 ft high. Aug. 



8. ELEtiCHABIS. 



Spikes single, terminal. Glumes imbricated all round with- 

 out much order. IVriunth reduced to 3 12, mostly 6, iL-M. 

 persistent bristles, surrounding the ovary. Stamens 8. Style 2 

 8-cleft, bulbous and persistent at base, forming a tubercle 

 crowning the achenium. Culms leafless, simple. 



* Culmi roundish, j/l 



1. E. obttisa. Spike-rusJi. 



Culms nearly terete In tufts ; spike more or less globose, at length becoming 

 somewhat cylindrical, obtuse, densely many-flowered ; glumes very obtuse, 

 light-brown, -whitish on the margin-; achenium obovate, of a shining brown, 

 surrounded by 6 bristles twice as long as Itself, and crowned with a very broad 

 and flat tubercle. A common species la shallow water and muddy grounds. 

 Culms 6> 12' high. July Aug. 



2. E. palustris. Hound Hush. 



Culm nearly terete; spike oblong-lanceolate, acute, many-flowered, often 

 obliquely attached ; glumes reddish-brown, whitish on the broad margin ; lower 

 ones sometimes empty; achenium obovate, surrounded by about 4 bristles 

 longer than itself, and crowned with a small, ovate, flattened tubercle. A quite 

 variable species ; very common In shallow water and low grounds. Culms & 

 20' high. June July. 



* Culms angular or comprised. 



3. E. tenuis. Slender Rush. 



Culm very slender and wiry, 4-anglcd, with concave sides ; spike elliptical, 

 somewhat acute at each end, 20 30 flowered ; glumes ovate, obtuse ; acbenjnra 

 obovate, with a small, depressed tubercle, and surrounded by 24 bristles, or 

 more- A common and very slender species In wet meadows, sufficiently dis- 

 tinguished by Its size, and the 4-angled culm ; 6' 12' high. June July. 



4. E. acicularis. Hair Eusli. 



Culm setaceous, 4-angled; spike oblong-ovate, 8 8-flowcred; glumes ob 

 long-ovate, obtnslsll, purplish on the margin ; achenlnm obovold-trlangular, 

 crowned with a conical tubercle. A very delicate species, common in muddy 

 grounds and edges of ponds, where the culms are as Bno as hairs, and If 0' 

 high. JuneJuly. 



4. SClRPUS. 



Spikes cylindrical, clustered, and furnished with an involucre, 

 sometimes single, terminal or lateral. Glumes imbricated all 

 round in no rixvd order. IVrianlh reduced to 3 6 bristles. 

 us 8. Style 2 3-cleft, not bulbous at base, deciduous. 

 Aeli.'iuuiii lenticular or triangular. Culms sheathed at base. 

 Spltet ItiteraL 

 t Ltafltn. 



\. S. dSbilis Slender ClubrusJi. 



Culms slender, farrowed, tufted, roundish, rarely with a single leaf at base ; 

 spikes few, generally about 34, ovoid, sessile, In a single cluster situated near 

 the top of the culm, the prolongation of which serves for an Involucre ; glumes 

 roundish-ovate, obtuse, pale yellowish-green; style 2 3-cIcft; achenlnm 

 obovate, shorter than the 4 6 bristles. A slender Rush of a pale-green color, 

 common In wet grounds. Culm 6' 12' high. Aug. 



2. S. lacfistris. Bulrush. 



Culm tall, cyllndrie, filled with spongy pith, tapering above, and ending In 

 aa abrupt point, dark-green; spikes oblong-ovate, numerous, arranged In a 

 compound panicle somewhat like an umbel, of a reddish-brown color ; glumes 

 ovate, mucronate ; acbenlam obovate, mucronate, surrounded by 4 6 bristles. 

 A tail, dark-gran Bush. Common In wet grounds, usually leafless, sometit 

 lib a single, subulate loaf. Culm 4-8 ft. high. July. 

 1 1 Culm KiA leave*. 



3. S. pungens. 



Club-ruslt. 



Culm acutely angled with concave sides ; leaves few, cartnate beluw, chan- 

 nelled above, often 6' S' Km. I. sessile, 16 In a cluster, -. 

 much shorter than the involucrul prolongation of the stem ; glume* 

 cleft, mucrunat' : bristles 24, shorter than the obovaU-. 

 nato achonlum. A common Rush growing in swamps, salt and fresh, and in the 

 borders of ponds and streams, distinguished by the sharply triangular stem, and 

 rather long, channelled leaves. July Aug. 



Spite* terminal. Culmi leafy. 



4. S. maritimus. Sea Clult-rufh. 



Culm acutely triangular, stout ; leaves flat, linear, rough on the margin, as 

 tall as the culm ; Involucre of 1 4 very unequal leaves ; spikes < 

 several in a sessile cluster, often with 1 or more on peduncles of unequu! 

 glumes ovate, 8-cleft ; achenlnm very broadly orbicular, flat on one side anil 

 convex on the other, longer than the 1 6 bristles surrounding It, which some- 

 times disappear. A stout Rush of the salt marshes, growing 18 ft hi. 

 spikes are of a rusty -brown color, and vary much In size. In the stoutest plants 

 they are cylindrical, and an Inch or more long. Aug. 



.5. S. atruvirens. Umbelled Club-ruth. 



Culm obtusely triangular, rigidly erect, leafy ; leaves broad-linear rough on 

 the margin, flat ; involucre of about 8 long leaves ; spike ovoid, crowded In 

 dense, globular, dark, dull-green heads, containing 1020 spikes ; these are ar- 

 ranged in a decompound, and mostly branching umbel of unequal <li 

 achenium obovate, compressed, scarcely shorter than tbo bristles. A < 

 leafy species, distinguished by the globose heads of splkelets arranged in the 

 decompound umbel. Culm 2 4 ft high. July, 



* * * Briellts capillary, twitting, much longer than tht achenium, at length 

 projecting from the rutty-brown scale*. 



6. S. lineatus. Dog-Rusli. 



Culm triangular, very leafy ; leaves linear, flat, rough on the margin ; spikes 

 oblong, at length cylindrical, solitary, nodding, on filiform pedicels, arr., 

 terminal ami axillary, panlculately-branchlng panicles ; upper panicle with an 

 involucre much shorter than Itself; bristles 6, scarcely longer than the acute 

 scales. A coarse, grassy species, common in wet meadows, 23 ft high. July. 



7. 8. Eriophorum. 



Wool-grass. 



Culm obscurely 8-angled, very leafy ; leaves narrow-linear, long, rough on 

 the margin ; leaves of the Involucre longer than the decompound, paatoahta 

 umbel, which Is composed of ovate, clustered or p ;>t!es 0. 



at length much longer than the obtuse scales, rust-colored. A coarse specie* 

 like the last, but distinguished at sight by Iti erect panicle or umbel. It varies 

 In the length of the branches of the umbel, and In some other respects. Culm 

 2 5 ft. high. July Aug. 



6. ERKjPHORUM. 



Spikes many-flowered. Scales imbricated all round without 

 onli'r. Perianth consisting of numerous, rarely <>. woolly. |"-r- 

 gistent bristles, much longer than the glumes. SUuneni mostly n. 

 Style 3-ck-ft. 



1. E. polystachyon. Cotton Grass. 



Culm rigidly erect, obscurely 8-angled ; leaves linear, flat, terminating In a 

 triangular point; Involucre 2 3-leavcd ; spikes about 10, on sU 

 rough or smooth peduncles. Wool straight, nearly an ineh lung. A < 

 spicnous and common inhabitant of bogs and meadows. Culmi 2 ft high. 

 June. 



2. E. grdcilis. Slrnder Cotton Grass. 



Culm slender, leafy, somewhat 8-angled, rough on the angles, with 

 sides; Involucre short, usually 1-lcaved ; spikes 2 7, small, nodding, on >lmrt 

 roughish peduncles ; wool white, much longer than the tlou > r. A :i- 

 mon species In bogs and swan i ; ;<! froui the last by itsnnn 



angular leaves. Culm 12 ft high. July Aug. 



3. E. Virginicum. Brown Cotton Grass. 



Culm rather stout, rigid, nearly terete, leafy ; leaves long, flat, narrowly- 

 linear, rough on the margin ; Involucre 2 t-leaved; spikes nearly sen--: 

 crowded In a dense head ; wool dense, of a rusty-brown color, 8 or 4 times as 

 long as the scale; stamen 1. A common species, sufficiently distinguished by 

 the short, reddish wool. Culm 28 ft. high. July Aug. 



