1 4 Cyperacece. {Cyperus 



i. CYPERUS, L. 



Perennial, rarely annual, glabrous herbs, with a creeping 

 rootstock or o; 1. all towards the base of the stem, with some- 

 times a few cauline, in a few sp. reduced to sheaths ; infl. of 

 solitary or umbelled heads or spikes of spikelets; invol. bracts 

 one or more, foliaceous, with bracteoles under the secondary 

 divisions of the infl.; spikelets linear or oblong, rhachilla 

 persistent, not disarticulating towards the base, with some- 

 times membranous wings (the persistent bases of the glumes) ; 

 glumes distichous, 2 lowest empty, the succeeding bisexual, 

 all nearly equal, deciduous in ascending order, uppermost 

 1-3, empty or sterile; hypogynous scales or bristles o; stam. 

 3, rarely 1 or 2, anth. linear or oblong; ov. compressed, style 

 long, short, or o, stigma 2 or 3, long or short ; nut trigonous,, 

 triquetrous, or plano-convex. — Sp. about 350; 80 in Fl. B. Ind. 



A satisfactory classification of the species of Cyperus in linear sequence 

 is, owing to their cross affinities, and their variability in habit and in 

 the development of the infl., perhaps unattainable. For this work (in 

 which dichotomy is the rule adopted by Dr. Trimen for the construction 

 of the keys), I have chosen for the principal subdivisions of the genus 

 characters which, though in great measure artificial, will, I think, be 

 serviceable to the student in his endeavour to identify the Ceylon species. 

 This I have followed with an account of the arrangement adopted by Mr. 

 Clarke in the Flora of British India, which is partly natural and partly 

 artificial ; — wholly artificial in retaining Juncellus as a genus, and natural 

 in adopting Pycreus. With regard to the latter genus, though not adopted 

 by Dr. Trimen in the list of Cyperacece, which he drew up for description 

 in this work, it is well distinguished from Cyperus by the laterally com- 

 pressed nut, and is, as Mr. Clarke informs me, only distinguishable 

 from Kyllinga by habit and the inarticulate rhachilla of the spikelets., 

 For valuable observations on the inflorescence, &c, of Cyperacece, see 

 that author's Presidential Address to the Linnean Society, published in. 

 the "Proceedings" of that body for 1895-6, p. 22. — J. H. D. 



Style long, filiform, stigmas 2-3, minute . . 1. C. Cephalotes. 

 Style very short or o, stigmas 3, short . . 2. C. Iria. 

 Style long, stigmas 2-5, long. 



Stigmas 2-3, nut dorsally compressed (see 



also 39, C. alopecuroides) . . . 3. C. PYGM^US. 

 Stigmas 2, nut laterally compressed. 



Spikelets all or most in a solitary terminal 

 head ; annuals. 

 Rhachilla not winged. 



Spikelets loosely capitate . . . 4. C. STRAMINEUS. 

 Spikelets compactly capitate . . 5. C. puMilus. 

 Rhachilla winged . . . . . 6. C. hyalinus (Vahl). 

 Spikelets umbelled. 



Style as long as the nut. 



Nut broadly obovoid . . . 7. C. SANGUINOLENTUS. 



Nut narrow, truncate . . . . 8. C. POLYSTACHYUS. 

 Style shorter than the nut. 



