3 66 



CYPERACEAE. 



VOL. I. 



17. Carex austrina (Small) Mackenzie. Southern Sedge. Fig. 884. 



C. Muhlenbergii var. australis Olney ; Bailey, Proc. Am. 

 Acad. 22: 141. 1886. Not C. australis T. Kirk, 1899. 

 C. Muhlenbergii anstrinns Small, Fl. SE. U. S. 218. 1903. 

 C. austrina Mackenzie, Bull. Torr. Club 34: 151. 1907. 



Culms erect, slender, sharply triangular, rough 

 above, i-2i tall. Leaves ii"-2i" wide, usually 

 noticeably shorter than culm ; sheaths tight, thick- 

 ened at mouth, not conspicuously septate-nodulose; 

 bracts i'-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 /i"- 

 15" long, 4"-/ti" thick; perigynia ascending, 2" long, 

 il" 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. 



18. Carex mesochorea Mackenzie. 

 Sedge. Fig. 885. 



Midland 



C. mediterranea Mackenzie, Bull. Torr. Club 33 : 439. 



1906. Not C. B. Clarke, 1896. 

 C. mesochorea Mackenzie, Bull. Torr. Club 37 : 246. 



1910. 



Culms slender, erect, rough above, usually about 

 10' tall. Leaves \\"-2" wide, usually about half 

 length of culm ; bracts of lower spike bristle-form, 

 short ; spikes few, androgynous, only the lower dis- 

 tinguishable, subglobose, densely clustered in a ter- 

 minal ovoid head $"-&' long, 5" thick; perigynia 

 ascending or spreading, if" long, the body ovate, 

 slightly more than i" 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. 



19. Carex cephalophora Muhl. Oval-headed 



Sedge. 



Fig. 886. 



Carex cephalophora Muhl.; Willd. Sp. PI. 4: 220. 1805. 



Pale green, culms slender, erect, rough above, S'-2 

 tall. Leaves i"-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?" long; perigynia narrowly to 

 broadly elliptic-ovate, broadest just below the middle of 

 body, ii" long, 1" wide, nerveless or nearly so, nar- 

 rowed 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. 



In dry fields and on hills, Maine and Ontario to Mani- 

 toba, south to Florida and Texas. Ascends to 2500 ft. in 

 Virginia. May-July. 



