216 CYPERACE^E. Cyperus. 



what flattened, 6- 12-flowered or more, spreading in rather loose clustered spikes 

 upon the more or less developed rays of the usually crowded umbel (often sessile on 

 the lower stems) : scales ovate, obtuse, a line long, but slightly carinate and obscurely 

 nerved : joints of the rhachis thick, broadly winged : nutlet brownish, oblong-ovate, 

 compressed-triangular, acute at each end. 



Near Fort Yurna (De Bary) and in marshes along the Colorado and Gila (Schott); New Mexico 

 (Emory, Wright), and common in the Atlantic States. 



9. C. ferax, Richard. Stem stout and tall, with broad and much elongated in- 

 volucral leaves, and bearing an open spreading compound umbel of numerous rays : 

 spikelets pale, scattered, horizontally spreading in loose subdistichous spikes, terete, 

 5 to 10 lines long, usually 8 10-flowered : scales oblong-ovate, obtuse, strongly con- 

 cave and scarcely carinate, obscurely 7-9-nerved, nearly 1 lines long, at length 

 spreading, twice longer than the thick broadly winged joints of the rhachis : nutlet 

 obovoid-oblong, obtuse and obtusely triangular, closely embraced by the wings. 

 Kunth, Euurn. ii. 89 ; Benth. Fl. Austr. vii. 286. 



A species widely spread through the tropical regions of the globe ; collected in California only 

 by Muir, the locality unknown. 



6. Spikelets 1 3-flou'ered, slender and subterete, often flexuous, acute or acumi- 

 nate (the upper flower usually undeveloped) : scales appressed, obtuse, sev- 

 eral^nerved : joints of the rhachis short, slender, narrowly winged: style 

 3-cleft and nutlet triangular. MARISCUS, Griseb. 



* Spikelets scattered in open spikes : umbel compound. 



10. C. Californicus. Stem stout and tall, triangular : involucre about 5-leaved, 

 the leaves much elongated, nearly 6 lines broad, very rough on the margins : rays 

 about 10, elongated (4 inches), bearing involucellate umbels with slender rays an 

 inch long or less : spikes 1 to 1 inches long, the spreading or somewhat reflexed 

 flexuous spikelets terete, attenuate upward, very slender, 2 to 4 lines long, 2-4- 

 flowered : scales oblong-ovate, a line long : nutlet unknown. C. speciosus, Torr. 

 Bot. Hex. Bound. 226. 



Collected in California by Rev. Mr. A. Fitch, but locality uncertain. In habit resembling forms 

 of the eastern C. strigosiis. 



* * Spikelets in dense cylindrical sessile sjtikes. 



11. C. flavamariscus, Griseb. Perennial, with creeping rootstock : stems 

 usually slender, acutely triangular, 1 or 2 feet high, exceeding the leaves : involucre 

 3 - 4-leaved : spikes about 5 (4 to 6), very dense, 6 to 8 lines long : spikelets spread- 

 ing, oblong-lanceolate, acute, 1 J lines long, 2-flowered, 1-fruited : scales yellowish or 

 brownish, ovate, about 11 -nerved : nutlet triangular-obovate, of a line long. Fl. 

 Brit. W. Ind. 567. Mariscus flavus, Vahl. M. HcenJcei, Presl, Rel. Ha3nk. i. 181. 

 C.flavus, Boeckeler, Linn, xxxvi. 384. 



From Mexico and the "West Indies to Brazil ; reported as collected by Haenke at Monterey. 

 C. pubescens, Presl, of the same collection and from the same locality, may perhaps be a radiate 

 form of this species, though described as pubescent throughout, which is a character otherwise 

 unknown in the genus. 



2. SCIRPUS, Linn. BULRUSH or CLUB-RUSH. 



Flowers perfect. Spikelets usually many-flowered, with the scales imbricately 

 and closely arranged around the rhachis, tjie lowest one or two often empty. Hy- 

 pogynous bristles 3 to 6, barbed or ciliate, or wanting. Stamens 1 to 3. Style 

 2 - 3-cleft, scarcely or not at all thickened at base, deciduous or only the base per- 

 sistent. Nutlet lenticular or more or less triangular, obovoid. Tufted annuals or 

 mostly perennials with creeping rootstocks, the stems sheathed or leafy at base, and 



