543 
CYPERACEJE. (SEDGE FAMILY.) 
tinguished by the smaller approximate spikes, longer and sharper 
scales, and especially, from every species in this subsection, by the 
smooth margin and beak of the perigynium. 
* * * * * Perigynia plano-convex, without a leak , of a thick and 
leathery texture , prominently nerved, smooth (except on the angles), 
with a minute and entire or slightly notched white membranaceous 
point: achenium conformed to the perigynium, crowned with the 
short thick style: bracts like the scales (brown), the lowest with a 
prolonged point: rootstock creeping. — Chordorhizjs. (Though 
externally dissimilar, the species in this subsection exhibit impor¬ 
tant points of affinity, and are nearly allied to each other, and more 
remotely to the next subsection.) 
27. C. chordorlliza, Ehrh. Culms branching from the long 
creeping rootstock , smooth and naked above, clothed at the base with 
short appressed leaves; spikes aggregated into an ovoid head; perigy¬ 
nia ovate, a little longer than the scale. — Peat-bogs, N. and VV. New 
York to Wisconsin and northward. 
28. C. gracilis, Ehrh. Spikes 2-4, very small, remote, with 
commonly 2 fertile flowers ; perigynia ovate, twice as long as the scale. 
(C. tenella, Schk. C. loliacea, Schk. Supp., not of L. C. disperma, 
Dew., fyc.) — Cold swamps, N. New England to Wisconsin. — A slen¬ 
der species, 6'-12' high, with long grassy leaves, growing in tufls. 
(Vide Gray in Sill. Jour. 2 Ser. 4, p. 20.) 
§ 3. Spikes pistillate above, staminate at the base. 
* Spikes roundish-ovoid, rather small, more or less distant on the zig¬ 
zag axis (closely aggregated in No. 30) : perigynia plano-convex, 
smooth, pale green, becoming whitish or silvery: scales white and 
membranaceous; the bracts resembling them, or prolonged and bris¬ 
tle-shaped. — Canescentes. 
- Perigynia somewhat thickened and leathery, distinctly nerved, with a 
smooth or very minutely serrulate short point, entire or slightly notch¬ 
ed at the apex. 
29. C. trisperma, Dew. Spikes 2-3, very small , with about 
3 fertile flowers, remote, the lowest with a long bract; perigynia oblong, 
with numerous slender nerves, longer than the scale. — Cold swamps 
and woods, especially on mountains. New England to Michigan. — 
Resembling the last, but taller, with larger spikes and fruit, and weak 
spreading culms. 
30. C. tcniliflora, Wahl. Spikes 3, few-flowered, closely ap¬ 
proximated; perigynia ovate-oblong, about the length of the broadly - 
ovate scale. — Cold swamps, N. New England and New York, north¬ 
ward. 
31. C, canesccns, L. (in part). Spikes 5-7 {about 12-20- 
flowered), the 2-3 upper approximated, the rest all distinct and the 
lowermost remote; perigynia ovate , about the length of the pointed 
