24 CYPERACEAE. 



small bract. Spikelets solitary or several in terminal umbels or clusters, pale : 

 scales imbricate in 2 rows, or in 3 rows by the twisting of the rachis, deciduous. 

 Perianth wanting. Style pubescent, with a swollen base, deciduous. Achenes 

 3 -angled, warty. 



1. A. monostachya (L.) Vahl. Leaf -blades nearly filiform above the dis- 

 colored bases, slightly involute, sharp-pointed: scapes tufted, very slender or 

 filiform, 1-4 dm. tall, erect, smooth: bracts of the involucre much shorter than 

 the spikelets, inconspicuous : spikelet solitary or sometimes 2 together, flattened, 

 ovoid or conic, 1-1.5 cm. long, pale: achenes slightly pear-shaped, 2-2.5 mm. 

 long, yellowish-white, often apiculate. Pinelands and open hammocks, L. keys. 

 [E. K.] (Bah., Cuba, Ant.) 



5. STENOPHYLLUS Eaf. Scapose tufted herbs. Leaves basal: blades 

 narrowly linear, filiform or setaceous, the sheaths ciliate or pubescent. Spike- 

 lets umbellate, capitate, or solitary, the scales spiral, mostly deciduous. 

 Involucre of 1-several bracts. Flowers perfect. Perianth none. Style gla- 

 brous, the base much swollen and persistent as a tubercle on the achene. 



1. S. ciliatifolius (Ell.) C. Mohr. Leaves erect; blades bristle-like or linear- 

 filiform, channeled, serrulate-ciliate : scapes tufted, very slender, 10-30 cm. tall, 

 often slightly scabrous near the top: bracts of the involucre 2-3, similar to the 

 leaves but shorter, one about as long as the umbel, the others very short: 

 spikelets numerous in a terminal compound umbel, linear-oblong, 2-4 mm. long, 

 acute, 6-12-flowered : scales broad, brown-margined, keeled, abruptly pointed, 

 often ciliate toward the apex: achenes 3-angled, obovoid, less than 1 mm. long, 

 bluish, minutely papillose. Low sandy places and open hammocks, L. keys. 



6. DICHROMENA Michx. Caulescent herbs with the spikelets crowded 

 in a terminal head involucrate by several bracts, which are often white at the 

 base. Spikelets compressed, several-many-flowered. Scales spirally imbri- 

 cate all around, several of them with imperfect flowers, or empty. Perianth 

 none. Style subulate. Achene lenticular, transversely rugose, crowned with 

 the broad persistent base of the style (tubercle). WHITE-TOP. 



1. D. colorata (L.) A. Hitchc. Stem slender, rather sharply triangular, 3-6 

 dm. tall: leaf-blades narrowly linear, much shorter than the stem: bracts of 

 the involucre reflexed when mature, yellowish-white at the base: head globose, 

 1-2 cm. in diameter: spikelets narrowly oblong, acute: scales membranous, 

 lanceolate, nearly white, subacute: achene-body obovoid, a little over 1 mm. 

 long, pale-brown, compressed. Low pinelands and open sandy places, L. keys. 

 (Ber., Bah., Cuba, Ant.) 



7. SCHOENTJS L. Acaulescent rush-like herbs. Leaf-sheaths dark-col- 

 ored: blades resembling the scapes, half -terete. Spikes in a terminal cluster, 

 1-8-flowered, subtended by an involucre of 1-2 bracts. Spikelets crowded, 

 often dark-colored: scales imbricate in 2 rows, persistent. Perianth of 3-6 

 scabrous or plumose bristles. Styles barely enlarged at the base, almost 

 wholly deciduous. Achene 3-angled, smooth. 



1. S. nigricans L. Leaf -sheaths dark-brown or almost black at the base; 

 blades erect, rigid, pungent: scapes tufted, 2-6 dm. tall: bracts of the invo- 

 lucre 2, the lower one surpassing the inflorescence: head about 1 cm. long, 

 dark chestnut- colored: spikelets flattened, 6-8-flowered, narrowed upward: 

 perianth-bristles 6, unequal, somewhat plumose: achenes oval, white and 

 polished, about 2 mm. long. Low pinelands, Big Pine Key. [E. K.] (Bah., 

 Cuba.) 



