CYPERACE.E. 421 



3. C. inficxus Mukl. : umbel 2 3-rayed, or conglomerate and sim- 

 ple ; involucre 3-leaved, very long; spikelets collected into ovate heads, 

 oblong, 8-flowered ; glumes squarrose at the tip. C. uncinatus Pursh. 



HAB. Banks of streams. Ver. to Vir. Aug., Sept. <. Culm 

 23 inches high, triquetrous. Heads consisting of many ovate 

 spikes, yellowish. 



4. C.jlavescens Linn. : spikes linear-lanceolate, in fascicles of 3 4; 

 glumes obtuse ; style 2-cleft ; seed lenticular ; involucre 3-leaved, 

 longer than the spikes. 



HAB. Wet soils. N. Y. to Car. Aug., Sept. U . Culm 8 12 

 inches high. Spikelets 14 20-flowered, yellowish- green. 



5. C. nuttalii Torr. : culm acutely triangular; umbel radiate or near- 

 ly sessile, loose ; rays short ; involucre 4-leaved ; 2 of the leaves very 

 long ; spikelets linear-lanceolate, compressed, acute ; stamens 2 ; 

 style 2-cleft ; seed oblong, obtuse, compressed. 



HAB. Salt marshes. N. S. Aug., Sept. L. Culms cespitose, 

 5 12 inches high. Spikelets very acute, green and brown. 



6. C. diandrus Torr. : culm slender, obtusely triangular ; umbel ses- 

 sile, or 1 2-rayed ; involucre 3-leaved, 2 of the leaves much longer 

 than the umbel ; spikelets lanceolate-oblong, much compressed, many- 

 flowered (14 16 ;) glumes margined, rather acute, keeled ; stamens 

 2 ; style 2-cleft j seed oval, compressed. 



HAB. Salt marshes and wet grounds. N. S. Culm 8 12 inches 

 high, slender. Umbel resembling a small panicle. 



7. C. dentatus Torr. : umbel compound, (6 10-rayed ;) involucre 

 3-leaved, longer than the umbel ; spikelets 3 on each ray, alternate, 

 ovate, compressed, 8-flowered ; glumes acute, nervose, spreading at 

 the points ; seed triquetrous. C.parviflorus MM. 



HAB. Swamps and marshes. N. S. Sept. 1C. Culm 1012 

 inches high. Spikelets much compressed, the tips of the glumes 

 spreading. 



8. C. erythrorhizos Maid. : umbel decompound ; involucrum 3 6- 

 leaved, very long ; spikes alternate, linear, horizontal, about 12-flow- 

 ered, nearly terete ; style 3-cleft ; seed triquetrous. 



HAB. Banks of streams. N. Y. to Geor. Aug., Sept. If.. 1 

 Root fibrous, red. Culm a foot high. Partial umbel nearly 

 naked. Spikelets linear, at length nearly round. 



9. C. strigosus Linn. : spikelets linear, compressed, acute, alternate; 

 glumes lanceolate, nervose ; umbel simple or compound ; involucre 

 about 6-leaved, pubescent on the margin ; root globose. 



HAB. Wet grounds. N. Y. to Car. Aug., Sept. If. Culm 

 2 3 feet high. Spikelets scattered, many -flowered. 



10. C. tennis MM. : spikes lanceolate, acute, 10 17-flowered ; um- 

 bel simple ; involucre 3 4-leaved, longer than the rays ; root tuber- 

 ous. 



HAB. Penn. and Vir. Muhl. Culm 8 inches high, slender. Spike- 

 lets lanceolate, many-flowered, yellow. 



36 



