40 CYPERACEAE 



Family 13. CYPERACEAE. Sedge Family. 



Flowers all perfect, or at least one in each spikelet perfect. 

 Glumes of the spikelets 2-ranked. 



Perianth represented by bristles; inflorescence axillary. 1. DULICHIUM. 



Perianth wanting; spikelets in terminal, solitary or umbellate heads. 



2. Cyperus. 

 Glumes of the spikelets spirally imbricate. 



Base of the style persistent as a tubercle on the achene. 



Basal empty glumes several. 3. Rynciiospor.^. 



Basal empty glumes wanting, or 1 or 2. 



Spikelets solitary ; stem leafless; bristles usually present. 4. Eleocharis. 

 Spikelets several or numerous ; stem leafy ; bristles none. 5. Stekophylll'S. 

 Base of the style not persistent as a tubercle. 



Base of the style swollen ; bristles none. 6. Fimbri.stylis. 



Base of the style not swollen; bristles usually present. 

 Flowers without any inner scales. 



Bristles much elongating in fruit, silky. 



Bristles 6, but each 4-6-cleft to near the base, therefore appearing 



numerous. 7. Eriophorxtm. 



Bristles 6, simple, crisp. 8. Leucocom.v. 



Bristles short, or little elongating, rarely wanting. 9. Scirpus. 

 Flowers with a small Inner scale between the flowei and the rachis. 



10. Hemicarph.\. 

 Klowers monoecious or dioecious. 



Achenes not enclosed in a perigynium. 



Spikes several, clustered ; glumes .subtending a single flower. 1 1 . Kobre.sia. 

 Spikes solitary ; glumes subtending 2 flowers. 12. Elyn.\. 



Aclienes enclosed" in a perigynium. 13. Oarex. 



1. DULICHIUM L. C. Rich. l. D. arundinaccinn. 



2. CYPERUS L. Galingale, Nut-grass. 



Glumes falling away from the persistent racMs of the flat spikelets. 



Style 2-cleft; achenes lenticular. 1. C. diandrus. 



Style 3-cleft; achenes 3-angled. 



Wings of the racliis none or very narrow. 

 Annuals: stamen 1. 



Glumes awned or mucronate. 2. C. inflexus. 



Glumes acute, neither awned nor mucronate. 3. C. acuminatus. 



Perennials; stamens 2 or 3. 



Glumes tipped with a ciu-ved or bent awn; perennials with a rootstock. 



4. C. Fendlerianus, 

 Glumes blunt or mucronate; perennials with a corm-like base. 



Heads oblong; spikelets ascending; stem rough. 5. C. Schweinitzii. 

 Heads short; spikelets more or less spreading; stem smooth. 



Glumes broadly ovate; achenes 1 .5-2 mm. long. 6. C. Houghtoni. 

 Glumes oblong-ovate; achenes 2-2.5 mm. long. 7. C. Bushii. 

 Wings of the racliis prominent and separating from it as interior scales. 



8. C. erythrorhiros. 

 Spike ets wholly falUng away, usually leaving the two lower glumes persistent. 



9. C. slrigosus. 



3. RYNCHOSPORA Vahl. Be.\ked Rush. i. R. alba. 



4. ELEOCHARIS R. Br. Spike-rush, Wire-grass. 



Style-branches 2; achenes lenticular or biconvex. 



Sheath hyaline, and scarious at the summit. 1. E. thermalis. 



Sheath firm, not scarious at the summit. 

 \nnuals, with fibrous roots. 



Achenes black, shining. 2. E. atropurpurca. 



Achenes pale brown, dull. 



Spikelets narrowly oblong or subcylindric ; glumes blunt, closely appressed. 



3. E. Engelmanni. 

 Spikelets lance-ovoid or lance-oblong; glumes acutish, more spreading. 



4. E. monticola. 

 Perennials, with rootstocks. 5. E. paluslris. 



Style-branches 3; achenes trigonous or turgid; perennials, with rootstocks. 



Achenes canceUate and longitudinally ribbed; spikelets flat. 6. E. acicularis. 



Achenes smooth, papillose or reticulate. 



Tubercle of the achenes short-conic to depressed, plainly distinguishable from 

 the achene. 

 Achenes papillose. 



Stem filiform; glumes obtuse. 7. E. tenuis. 



Stem flat; glumes acute. 8. E. acuminata. 



Achenes liiiclv nticulated. 9. E. arenicola. 



Tubercle of the achenes long-conic, scarcely distinguishable from the body of the 



achene. 10. E. rostellata. 



5. STENOPHYLLUS Raf. l- S. capillaris. 



