694 CYPERACE^E STENOPHYLSLU 



RYNCHOSPORA 



pressed, narrowly ovate or linear-oblong, acute, broader than the stem, 

 2-10-flowered, 1-4 lines long, 3^ line wide : scales oblong, obtuse, or the 

 upper subacute, thin, pale green, usually with a narrow brown stripe on 

 each side of the midrib, deciduous, many of them commonly sterile : brist- 

 les 2-4, fragile, fugacious, shorter than the achene: stamens 3: style 

 3-cleft: achenes obovoid-oblong : tubercle conic, acute, % as long as the 

 achene. In wet soil, throughout North America: also Europe and Asia. 



E. rostellata Torr. Fl. N. Y. ii, 347. Perennial by a short caudex : 

 stems slender, the fertile erect, the sterile reclining and rooting at the 

 apex, 1-5 feet long : upper sheaths truncate : spikes oblong, narrowed at 

 both ends, thicker than the stem, 10-20-flowered, 4-6 lines long, about a 

 line in diameter : scales ovate, obtuse or the upper acute, green with a 

 somewhat darker midrid and slightly scarious margins : bristles 4-8, longer 

 than the achene and tubercle : stamens 3 : style 3-cleft : achene oblong- 

 obovoid, obscurely 3-angled : tubercle conic-subulate, about half as long a 

 the achene. Brit. Columbia to California and the Atlantic States. 



7 STENOPHYLLUS Raf. Neog. 4, (1825.) 



Annual herbs with slender erect stems, narrowly linear or fili- 

 form leaves with ciliate or pubescent sheaths and perfect flowers 

 in umbellate, capitate or solitary spikelets subtended by a one- to 

 several-leaved involucre. Scales spirally imbricated all around, 

 mostly deciduous. Perianth wholly wanting. Stamens 2 or 3. 

 Style 2- or 3-cleft, glabrous, at base much swollen and persistent 

 on the achene as a tubercle. Achene 3-angled, turgid or lenticular. 



S. capillaris Britton Bull. Torr. Bot, Club xxi, 30. Fimbristylis cap- 

 illaris Gray. Stems filiform, densely tufted, erect, grooved, smooth, 2-10 

 inches high: leaves filiform, roughish, much shorter than the stem, their 

 sheaths more or less pubescent with long hairs: inyolucral leaves 1-3, se- 

 taceous, shorter than or one of them exceeding the inflorescence : spikelets 

 narrowly oblong, somewhat 4-sided, 2-4 lines long, less than a line thick, 

 several in a simple or compound umbel, or sometimes solitary : scales ob- 

 long, obtuse or emarginate, pubescent, dark brown with green keel: 

 stamens 2: style 3-cleft: achenes yellowish brown, narrowed at base, very 

 obtuse or truncate at the summit % h'ne long, 3-angled, transversely 

 wrinkled: tubercle minute, depressed. In dry or moist soil throughout 

 North America. 



8 RYNCHOSPORA Vahl. Enum. ii, 229. (1806.) 



Leafy- stemmed herbs with erect 3-angled or terete stems, nar- 

 row flat or involute leaves and small flowers in variously clustered 

 spikelets. Scales thin, 1-nerved, imbricated all around, usually 

 mucronate by the excurrent midrib, the lower empty. Upper 

 flowers imperfect, the lower perfect. Perianth of 1*20 barbed or 

 scabrous bristles or none. Stamens commonly 3. Style 2-cleft, 

 2-toothed or entire. Achenes lenticular or swollen, capped by the 

 persistent base of the style, or sometimes by the whole style. 



R. alba Vahl Enum. ii, 236. Pale green: rootstock short: stems 

 slender or almost filiform, glabrous, 6-20 inches high: leaves setaceous, 

 3^-% line wide, shorter than the stem : spikelets several or numerous, iri 

 1-4 dense corymbose terminal and axillary clusters, narrowly oblong, 

 acute, at both ends, 1-3 lines long: scales ovate or ovate-lanceolate, white, 

 acute : bristles 9-15, downwardly barbed, slender, about as lonyj as the 

 achene and tubercle: achene obovate-oblong, smooth, pale brown, lenticu- 



