533 
CYPERACEJE. (SEDGE FAMILY.) 
4. R. gracilcnta, Gray. Leaves narrowly linear; spikes 
ovoid, crowded in 2-4 small clusters, the lateral long-peduncled; 
achenium ovoid, rather shorter than the bristles, about the length of the 
flattened awl-shaped tubercle. — Low grounds, S. New York and 
New Jersey. Aug. — Culm very slender, 1° -2 s high. 
Bristles denticulate or barbed downwards {in JVo. 9 both ways). 
5. R. alba, Vahl. Leaves almost bristle-form ; spikes (whitish) 
several, corymbed-clustered, lanceolate; achenium ovoid, narrowed at 
the base, shorter than the 9-11 bristles, a little longer than the slender 
beak-like tubercle ; stamens usually 2. — Bogs, common. July, Aug. 
— Culm slender, 12'-20' high. 
6. R« capillacea, Torr. Leaves bristle-form; spikes 3 —6 in 
a terminal cluster, and mostly 1 or 2 on a remote axillary peduncle, 
oblong-lanceolate (pale chestnut-color, J' long); achenium oblong-ovoid, 
stipitate, about haJf the length of the 6 stout bristles, and twice the 
length of the lanceolate-beaked tubercle. — Bogs and rocky river- 
banks, New York to Michigan. July. — Culm 6'-9'high, slender. 
Achenium very obscurely wrinkled. 
7. R. Knieskerilii, Carey. Leaves narrowly linear , short; 
spikes numerous, crowded in 4 - 6 distant clusters, oblong-ovate (chest¬ 
nut-color, scarcely 1" long) ; achenium obovate, narrowed at the base, 
equalling the 6 bristles, twice the length of the triangular flattened tu¬ 
bercle. — Pine barrens of New Jersey on bog iron-ore banks exclu¬ 
sively, Knieskern. Aug. — Culms tufted, 6'-18' high, slender: leaves 
short. 
8. R. glomcrata, Vahl. Leaves linear, flat; spikes numer¬ 
ous in distant clusters or heads (which are often in pairs from the same 
sheath), ovoid-oblong (brown) ; achenium obovate, margined, narrow¬ 
ed at the base, as long as the lance-awl-shaped flattened tubercle, 
which equals the (always) downwardly barbed bristles. — Low grounds, 
common, especially southward. Aug. —Culm l°-2° high. 
9. R. ceplialailtlia, Torr. Leaves narrowly linear, flat, 
keeled; spikes very numerous , crowded in 2-3 or more dense globular 
heads which are distant (and often in pairs), oblong-lanceolate , dark 
brown ; achenium orbicular-obovate, margined, narrowed at the base, 
about as long as the awl-shaped beak, half the length of the stout 
bristles, which are barbed either dotonwards or upwards. — Sandy 
swamps, Long Island to New Jersey. Aug. — Culm stout, 2?-3° 
high : fruit, &c., larger than in the last. 
14. C LABIUM, P. Browne. Twig-rush. 
' Spikes ovoid or oblong, of several loosely imbricated scales ; the 
lower ones empty, one or two above bearing a staminate or imper¬ 
fect flower, the terminal one perfect and fertile. Perianth none. 
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