72 Cyperaceae 



what pubescent or nearly glabrous, rough on the margins; in- 

 volucral bracts linear-subulate, acuminate, scabrous, 15-25 mm. 

 long, shorter than the rays; spikelets umbellate, solitary on the 

 ends of the rays, ovate to linear-oblong, 8-18 mm. long; scales 

 ovate, obtuse, mucronate, dull brown, pubescent; style 2-cleft, 

 flattened and ciliate ; achene obovate, lenticular, obscurely striate, 

 1.5 mm. long; tubercle soon deciduous. 



Hot Springs, near San Bernardino, Wright; Waterman's Hot Springs, 

 Parish. 



5. SCHOENUS L. 



Ours perennial herbs from rootstocks, with slender 

 erect tufted stems and slender subterete basal leaves. 

 Involucral bract erect appearing as a continuation of the 

 stem. Spikelets sessile in capitate lateral clusters, few- 

 flowered. Scales imbricated in 2 rows, the lower ones 

 empty, the upper bearing perfect flowers. Perianth of 6 

 scabrous or pubescent bristles. Stamens 3. Style 

 3-cleft, not dilated at the base. Achene more or less 

 3-angled, with a very short beak. 



1. S. nigricans L. Stems tufted, slightly compressed, slender, 

 5-7 dm. high ; leaves rigid, subterete, channeled, rough on the mar- 

 gins, shorter than the stems; sheaths black; involucral bract 

 3-5 cm. long; spikelets capitate clustered, ovate lanceolate, com- 

 pressed, 6-8-flowered; rachis zigzag; scales ovate, acute, com- 

 pressed, keeled, very dark brown; bristles 6, unequal, dilated at 

 the base, barbed above, longer than the achene; achenes globose- 

 oblong, 3-angled, white and shining. 



Arrowhead Hot Springs, near San Bernardino, Parish. Otherwise known 

 in North America only from Florida . 



6. CLADIUM R. Br. 



Perennial herbs with stout rootstocks, stout tall leafy 

 stems and elongated channeled leaves. Spikelets small, 

 usually clustered in terminal corymbs, panicles or 

 cymes. Scales mostly about 5, closely imbricated, brown, 

 the lower empty, the terminal one fertile and the 1-2 



