This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Acad. 22: 141. 1886. Not C. australis T. Kirk, 1899.
C. Muhlenbergii austrinus Small, Fl. SE. U. S. 218. 1903.
Culms erect, slender, sharply triangular, rough above, 1°-2 1/2° tall. Leaves 1 1/4"-2 1/4" wide, usually noticeably shorter than culm; sheaths tight, thickened at mouth, not conspicuously septate-nodulose; bracts ¥-2' long, dilated and much nerved at base, long-cuspidate and conspicuous; spikes numerous, androgynous, ovoid or subglobose, aggregated, the lower distinct but not separate, forming a head 7 1/2" - 15" long, 4"-7 1/2" thick; perigynia ascending, 2" long, 1 1/2" wide, the body suborbicular, nerved on outer and nearly nerveless on inner face, contracted into a 2-toothed beak half length of body; scales hyaline, strongly several-nerved, ovate, strongly awned, as wide as and longer than perigynia; stigmas 2.
In dry sunny places, Missouri and Kansas to Arkansas and Texas. April-July.
C. mediterranea Mackenzie, Bull. Torr. Club 33: 439.
1906. Not C. B. Clarke, 1896. C. mesochorea Mackenzie, Bull. Torr. Club 37: 246.
Culms slender, erect, rough above, usually about 10' tall. Leaves 1 1/4"-2" wide, usually about half length of culm; bracts of lower spike bristle-form, short; spikes few, androgynous, only the lower distinguishable, subglobose, densely clustered in a terminal ovoid head s"-8i" long, 5" thick; perigynia ascending or spreading, 1 3/4" long, the body ovate, slightly more than 1" wide, nerved on outer and nerveless on inner face, contracted into a 2-toothed beak half length of body; scales ovate, cuspidate, from slightly shorter to slightly longer and a little narrower than perigynia; stigmas 2.
In dry places, District of Columbia to Tennessee and Kansas. May-July.
Carex cephalophora Muhl.; Willd. Sp. PI. 4: 220. 1805.
Pale green, culms slender, erect, rough above, 8'-2° tall. Leaves 1"-2" wide, sometimes overtopping the culm, usually shorter; bracts of the lower spikes bristle-form, usually short; spikes few, androgynous, only the lower distinguishable, subglobose, densely clustered in a terminal ovoid head 4"-7 1/2" long; perigynia narrowly to broadly elliptic-ovate, broadest just below the middle of body, 1 1/4" long, \" wide, nerveless or nearly so, narrowed into a 2-toothed beak shorter than the body; scales ovate, thin, green or slightly yellowish in age, acuminate to cuspidate, the body strongly exceeded by the perigynia; stigmas 2.