s.); scattered in the warmer parts of the world, in Am. n. to Que., Ont., Minn., Ore. 

 and Alas.; probably adv. in Tex. 



37. Cyperus strigosus L. Fig. 235. 



Tufted perennial (occasionally flowering the first year); culms 4-10 dm. long, 

 subbasally 3-9 mm. thick (at the extreme base swollen tuberlike), just below the 

 inflorescence trigonous and 1.7-3 mm. thick; leaves 2-8 mm. broad, firm, the 

 longer ones about equaling the culm; inflorescence 7-30 (^0) cm. long, of 4 to 11 

 very unequal primary peduncles the shorter of which bear spikes 13-25 mm. long 

 and 2-4 cm. thick, each spike with 20 to 40 divaricately spreading spikelets in 

 several ranks, the longer peduncles in turn bearing a few secondary peduncles 

 (often very short) each with a spike 15-35 mm. long and 20-45 mm. thick, each 

 spike with 25 to 70 spreading spikelets; bracts 3 to 10, the longer ones far-sur- 

 passing the inflorescence; spikelets linear, straight, (10-) 12-25 (-29) mm. long, 

 1-2 mm. broad, less than half as thick as broad, golden-brown or tawny-brown, 

 with 5 to 20 scales (the terminal one sterile, tending to become involuted and 

 forming a short point), the axis at maturity detaching as a unit from the spike axis, 

 the internodes on the fertile side with 2 narrow hyaline wings 1 .5-2 mm. long, 

 about 0.4 mm. broad; scales 3.7-4.5 mm. long, 1.2-1.8 mm. broad, with 7 or 9 

 nerves, overlapping, usually persistent or less commonly belatedly deciduous either 

 before or after the axis falls from the plant; stamens 3; achene 1.5-2 mm. long 

 (usually about half as long as the scale), 0.5-0.6 mm. thick, trigonous, linear- 

 oblong, brown, basally substipitate, short-apiculate. 



Frequent in bogs and marshy areas, in shallow water of ponds and lakes and 

 in mud, in Okla. (McCurtain, LeFlore, Ottawa, Sequoyah, Craig, Johnston, Alfalfa 

 and Mayes cos.), e. and s.e. Tex., less frequent in n.-cen. Tex. and rare in the 

 Panhandle (genetically dilute plants rare elsewhere), and Ariz. (Pima Co.), 

 summer-fall; e. U.S. n. to Que., Ont., Minn., w. to Neb., Kan., Okla. and Tex.; 

 also Pac. States. 



38 Cyperus tenuis Sw. 



Tufted perennial; culms 3-8 dm. long, basally 2-7 mm. thick, just below the 

 inflorescence 1.1-2.8 mm. thick; leaves 1.5-5 mm. broad, the longer ones about 

 equaling the culms; inflorescence 6-20 cm. long, of 4 to 11 extremely unequal 

 primary peduncles the shorter of which bear spikes 2-3 cm. long and 15-25 mm. 

 thick, each spike with 14 to 30 divaricately spreading spikelets in 3 or 4 ranks, the 

 longer peduncles each with a spike 25-40 mm. long and 18-27 mm. thick, each 

 spike with 19 to 45 spikelets, the spikes occasionally compound with 1 or 2 smaller 

 nearly sessile spikes basally; bracts 3 to 11, the longer ones far-surpassing the 

 inflorescence; spikelets linear, straight, 10-15 mm. long, 0.7-1.3 mm. broad, about 

 half as thick as broad, grayish-brown, with 3 to 6 scales (the terminal 1 sterile, 

 tending to become involute and forming a short point), the axis at maturity de- 

 taching as a unit from the spike axis, the internodes on the fertile side with 2 

 narrow hyaline wings 1.5-2 mm. long and 0.3-0.5 mm. broad; scales 3.5-5 mm. 

 long, 1-1.6 mm. broad, with 7 or 9 nerves, overlapping, persistent; stamens 3; 

 achene 1.3-1.6 mm. long, less than half as long as the scale, 0.5-0.6 mm. thick, 

 trigonous, ellipsoid to obovoid-ellipsoid, brown, very minutely stipitate, apiculate. 

 Incl. var. lentiginosus (Millsp. & Chase) Kiikenth., C. strigosus var. gracilis Britt., 

 C. lentiginosus Millsp. & Chase. 



Infrequent in s. part of s.e. Tex. (San Patricio and Nueces cos.) and coastal 

 parts of Rio Grande Plains (Duval, Karnes and Cameron cos.), in wet or moist 

 clayey loam, summer-fall; n. S.A. w. to C.A. and Mex., n. to Sin. and Tex.; also 

 (?) Afr. 



457 



