42. Cypenis ovularis (Michx.) Torr. Figs. 236 and 237. 



Tufted perennial; culms, basally with tuberous enlargements, 25-80 cm. long, 

 sub-basally 1-3 mm. thick, just beneath the inflorescence 0.6-2 mm. thick; leaves 

 1.5-5 mm. broad, the longer ones about equaling the culms; inflorescence (1-) 

 3-12 cm. long, of (1 to) 3 to 8 very unequal peduncles each with a dense spherical 

 or prolate-spherical head 7-19 mm. long and 7-18 mm. thick, with (70 to) 100 to 

 240 spikelets borne spirally or in many ranks, about equally dense at top and 

 bottom, the upper spikelets ascending, middle ones spreading and lower ones 

 retrorsely appressed; secondary peduncles absent; bracts (2 or) 3 to 7, the longer 

 ones far-exceeding the inflorescence; spikelets 3.5-9 mm. long, 0.5-1 mm. broad, 

 about half to three fourths as thick as broad, straw-brown to dark-brown, with 2 to 

 4 scales ( the terminal one or two sterile and forming a blunt point, not an awn), 

 straight, the axis at maturity detaching a unit from the head axis, the internodes on 

 the fertile side with hyaline wings 1-2 mm. long and 0.3-0.7 mm. broad, usually 

 not clasping the achene; fertile scales 2.5-4mm. long, 1.2-2 mm. broad, obtuse, 

 with about 9 nerves well-distributed over the width, overlapping, persistent; stamens 

 3; achene narrowly oblong, 1.8-2.2 mm. long, 0.5-0.7 mm. thick, trigonous, brown 

 substipitate, apiculate. Inc. var. sphaericus Boeck. and var. robustus Britt., C. 

 Wolfii Wood. 



Infrequent in moist or wet sand, wet soil on edge of lake and banks of ditches, 

 in Okla. (Carter, Pittsburg, Pushmataha and LeFIore cos.), e., s.e. and n.-cen. Tex., 

 spring-fall; e. U.S. n. to N.Y., Pa., O., Ind., 111. and Mo., w. to Kan., Okla. and 

 Tex. 



The description above applies to the typical form. A more common form is the 

 var. cylindricus (Ell.) Torr. (C. retrorsus Chdipva.) with narrower and proportion- 

 ally more elongate heads (actually short spikes), paler and with a slightly more 

 tawny-ochraceous tinge, with fewer spikelets on the average (50 to 100), only 2 or 

 3 scales per spikelet, the wings averaging slightly narrower, the wings, scales and 

 achene averaging shorter. 



43. Cyperus globulosus Aubl. Fig. 238. 



Tufted perennial; culms slightly tuberous-enlarged basally, 1-8 dm. long, sub- 

 basally 1.5-2.5 mm. thick, just beneath the inflorescence 1-1.7 mm. thick; leaves 

 1.5-3 mm. broad, the longer ones about equaling the culms; inflorescences 2-8 

 cm. long, of 3 to 14 very unequal peduncles each with a dense head 7-15 mm. long 

 and 8-17 mm. thick, with 25 to 70 spikelets borne spirally or in a number of ranks, 

 about equally dense throughout, the upper spikelets ascending, the middle ones 

 spreading, the lower spreading or slightly descending but never retrorsely appressed; 

 secondary peduncles absent; bracts 4 to 11, the longer ones far-exceeding the inflor- 

 escences; spikelets 5-10 mm. long, 0.7-1.3 mm. broad, almost as thick as broad, 

 greenish-brown to ochraceous-brown or olive, with 3 to 8 scales (the terminal one 

 sterile or staminate and forming a short point, or blunt), straight, the axis at 

 maturity detaching as a unit from the head axis, the internodes with hyaline wings 

 0.8-1.4 mm. long and 0.25-0.6 mm. broad and not clasping the achene; scales 

 2.5-3 mm. long, 1-1.3 mm. broad, obtuse, with usually 9 well-distributed nerves, 

 overlapping, persistent; stamens 3; achene narrowly oblong, 1.3-1.6 mm. long, 

 about 0.6 mm. thick, trigonous, brown, substipitate, subapiculate. 



Frequent in moist or dry sandy soil, wet clay meadows and wet depressions, 

 in Okla. [Waterfall), e. and s.e. Tex., rare and in genetically dilute from inland 

 to n.-cen. Tex., summer-^fall; n. reputedly to Va. and Mo. 



10. Cladium P. Br. 



About 55 species of tropical and temperate regions, especially Australia; our 

 species almost cosmopoHtan. 



461 



