CYPERACEAE. 



VOL. I. 



31. Cyperus hystricinus Fernald. 

 Bristly Cyperus. Fig. 751. 



Cyperus hystricinus Fernald, Rhodora 8: 127. 

 1906. 



Perennial by corms and rootstocks ; 

 culms rather stout, smooth throughout, 3 

 tall or less. Leaves smooth, i"-3" wide, 

 the basal ones shorter than the culm, those 

 of the involucre about as long as the umbel ; 

 rays 14 or fewer, the longer 7' long or less ; 

 heads obovoid, or obovoid-cylindric, i'-ii' 

 long ; spikelets yellowish-brown, subulate, 

 2"-4" long, the uppermost spreading, all 

 the others strongly reflexed, bearing i or 2 

 achenes ; fertile scales strongly nerved ; 

 stamens 3 ; achene linear, trigonous, about 

 li" long, 3-4 times as long as the scale. 



Dry sandy soil, New Jersey and eastern 

 Pennsylvania to Georgia and Texas. Except 

 for the smooth culm and leaves closely re- 

 sembling C. retrofractiis. July-Sept. 



32. Cyperus Torreyi Britton. Pine-barren 

 Cyperus. Fig. 752. 



Mariscus cylindricus Ell. Bot. S. C. & Ga. i : 74. 1816. 

 Cyperus cylindricus Britton, Bull. Torn Club 6: 339. 1879. 



Not Boeckl. 1859. 

 C. Torreyi Britton, Bull. Torn Club 13: 215. 1886. 



Perennial by small hard corms, culms slender, smooth, 

 usually tufted, 4'-i8' tall, longer than the leaves. Leaves 

 smooth, i"-ii" wide, the longer ones of the involucre 

 much exceeding the umbel; umbel simple, several- 

 rayed, the rays short, or the longer I'-zi' long, the 

 sheaths 2-toothed ; heads very dense, cylindric, i'-i' 

 long, 2"-4" in diameter; spikelets ii"-2" long, flattish, 

 l-2-flowered, spreading or the lower reflexed; scales 

 green, oblong; rachis winged; stamens 3; style 3-cleft; 

 achene linear-oblong, 3-angled, apiculate, slightly more 

 than one-half as long as the scale. 



In sandy pine barrens and on the sea shore, southern New 

 York to Florida, west to Missouri and Texas. July-Sept. 



33. Cyperus ovularis (Michx.) Torr. Globose Cyperus. Fig. 753. 



Kyllingia ovularis Michx. Fl. Bor. Am. 1 : 29. 1803. 

 Cyperus ovularis Torr. Ann. Lye. N. Y. 3 : 278. 1836. 



Perennial by hard tuber-like corms, culms usually 

 strict, smooth, 8'-2i tall, longer than the leaves. 

 Leaves smooth, 2"-$" wide, the longer ones of the 

 involucre exceeding the umbel ; umbel mostly simple, 

 few-rayed, the rays rarely more than 2*' long; sheath 

 of the rays truncate or slightly toothed ; heads globose 

 or sometimes a little longer than thick, 4" -7" in di- 

 ameter, very dense, the spikelets radiating in all direc- 

 tions ; spikelets 2."-$" long, usually 3-flowered, separat- 

 ing from the axis and leaving a scar at maturity; 

 rachis winged ; scales ovate or ovate-lanceolate, obtuse 

 or subacute, green, strongly several-nerved ; stamens 3 ; 

 style 3-cleft ; achene linear-oblong, 3-angled, 2-3 times 

 as long as thick. 



In dry fields and on hills, southern New York to Florida, 

 west to Illinois, Kansas and Texas. Hedge-hog Club-rush. 

 July-Sept. 



