20 



CYPEEACEAE. 



Spikelets many-flowered, unisexual, more numerous in the staminate than in the 

 pistillate panicles, the rachilla articulate in the pistillate spikelets. Scales 

 many, acute, the flowering scales long and broad, firm, membranous, or nearly 

 coriaceous. 



1. D. spicata (L.) Greene. Stems 1-6 dm. long: leaf -blades 2-4 mm. wide: 

 panicle 2-6 cm. long: spikelets 8-18 mm. long, 6-16-flowered, pale-green, the 

 flowering scales 3-5 mm. long, acute or acuminate. — Coastal sand-dunes and 

 hammocks, U. S. keys, L. keys, L. S. keys. — [E. K.] — (Bah., Cuba, Ant.) — 

 Spike-grass. 



Family 2. CYPEEACEAE. Sedge Family. 



Grass-like or rush-like caulescent or scapose herbs, often with root- 

 stocks. Stems or scapes solid, or rarely hollow, often 3-sided or 3-angled. 

 Leaves with closed sheaths: blades narrow. Flowers perfect or imperfect, 

 in spikelets, one (rarely 2), in the axil of each scale (glume, bract), the 

 spikelets clustered or solitary, 1-many-flowered. Scales 2-ranked or 

 spirally imbricate. Perianth of bristles, or scale-like parts, or wanting. 

 Androecium of 1-3 stamens, or rarely more. Gynoeeium of 2 or 3 united 

 cari^els. Fruit an achene. 



Spikelets perfect, or mainly so. rarely 2 scales and 1 flower. 

 Scales of the spikelets 2-ranked : spikelets several or many 



together in each spike. 

 Scales of the spikelets spirally imbricate all around, or 

 2-ranked in Abildgaardia in which each scape is ter- 

 minated by one spikelet. 

 Perianth present. 

 Perianth wanting. 



Achene not surmounted by a tubercle. 



Spikelets terete, the scales spirally imbricate. 

 Spikelets flattened, the scales 2-ranked. 

 Achene surmounted by a tubercle. 



Spikelets in umbels or cymes, without an imbricate 



Involucre. 

 Spikelets in a head subtended by an imbricate in- 

 volucre. 

 Spikelets polygamous, or rarely of 4 scales and only 1-flowered. 

 Scales of the spikelet 2-ranked. 

 Scales of the spikelets spirally imbricate. 

 Stigmas 3 : style deciduous. 

 Inflorescence paniculate. 

 Inflorescence capitate. 

 Stigmas 2 : style persistent. 



1. ClTEKUS. 



2. Eleocharis. 



3. FlMBRISTYLlS. 



4. Abildgaardia. 



5. Stenophyllus. 



6. DiCHROMENA. 



7. SCHOENUS. 



8. Mariscus. 

 0. Remirea. 



10. RYXCHOSrORA. 



1. CYPERUS [Tourn.] L. Scapose herbs. Leaves basal: blades narrow. 

 Scapes, in our species, simple, triangular, and with one or more bracts at the 

 summit forming an involucre to the umbellate or capitate inflorescence. Pays 

 of the umbel sheathed at the base, usually very unequal, one or more of the 

 heads or spikes commonly sessile. Spikelets flat or nearly terete. Perianth 

 none. Achene not tubercled. — Galingale. 



Style-branches or stigmas 2 : achene lenticular. 

 Style-branches or stigmas 3 : achene trigonous. 



Kachis of the flattened spikelets persistent, the scales falling 

 away. 

 Wings of the rachis none or very narrow. 



Leaves not viscid : achenes about as wide as 



about y-^ as long as the scale, beakless. 

 Leaves viscid : achenes much longer than wide, 

 i/^ as long as the scale, beaked. 

 Wings of the rachis manifest. 

 Uachis of the spikelets deciduous. 



long, 



!ll)OUt 



1. C. paniculatus. 



2. C. cotnpressua. 



3. C. elegans. 



4. C esculcntus. 



