

J 



CLARKE — THE CYPEBACEAE OF COSTA KiCA. 447 



arra 



more loosely imbricated, less polished, sometimes variegated chestnut color and green. 

 Disthibution: Both in Central America and in Argentina. 

 Costa Rican collections: Vol can de Poas^ altitude 2,500 meters, Tondaz 107G3. 



6. Pycreus elegantulus^ C. B. Clarke in Dur. & Schinz, Fl. Afr. 5: 530. 1895. 

 Cyperus eleganiulus Steud. Flora 25: 583. 1842. 

 Cypervs nmidmis J. R. & C. B. Presl, Rol. Hat^iik. 1: 166. 1830. 

 Distribution: Quite common in Africa, l^reciuent in America all the way from 



Mexico to Southern Brazil. 



Costa Ricax collections: K1 Cepey, altitudes 1,800 meters, Tondaz, 12335; 



Carrillo, Cooper, 590. 



This species is not easily distinguishable fmm small specimens of i\ melanO' 



tit achylic. 



-^- 



bPECIES OK I'YCRKUS TO BE LOOKEO FOR IN COSTA KICA. 



PvcKEUs POLYSTACHYL's Bcauv. Fh d'Owar. 2: *1S. pJ. Sfi ft<j- 2. 1807. 



DiSTiunuTiON: In all the warmer parts uf the world. Occurs in the "West Indies in 

 many varieties and quite eonnnonly; not yet received from Costa Rica. The plant 

 resembles P. propinqnus and P, hdvjis. its spikcUls reddish. 



3. CYPERUS L. 



Spikelets 5 to many-flow errd; rachilla persistent; t^vo low^est glumes empty, the 4 

 or more next succeeding distichous, l)isexua1, perfecting nuts, deciduous fnun the bai^e 

 upward, a few of the uppermost glumes sterile or vacant, somewhat triserial; hypngy- 

 nous bristles none; stamens 1 to 3, anterior; style-branches 3; nut trigonous, ihe 

 anterior angle not rarely mon^ or less depressed.— Plants glabrous. Stems naked 

 except near the bape. there leafy. Spikelets in digitately or spicately clustered spikes. 



warm 



common in hot countries, rare in cold. 



KEY TO TUK SPECIES. 



Spikelets digitate or congested. (Pvcnohtachvae.) 



Annuals (here also C. haspan, no. 3;. 



Stem monocephalous; spik(^lets green 1. C. tenerrimus. 



Spikes umbellate, ferruginous or brownish 2. C undrmtus. 



Perennials. 



Stamen 1; plants large or of middh^ size. 



Rays of the umbel short. 



Leaves transversely hneolate - . - 6. C virens. 



Leaves not transversely lineolate. 



Spikelets much compressed 7. C. surinamcTisis 



Spikelets turgid, (ongested 8. C, lic^idae. 



Rays of the umb<'l longer than the stem 9. C. simplex. 



Stamens 2 or 3; steins Ix^aring many spikes. 

 Spikeh4s 1 1<» 2 mm. wide; n\it small. 



Cdumes imbricated 3.6'. Impan. 



Glumes distant, forming a loose spikelet . . 11. C. chorisanlhus. 



Spikelets 2 to 3 mm. wide. 

 Stems leafless. 



Plant dioecious ,.. - 5. C. canus. 



Spikelets bisexual - - - - 4. C. alternifohm. 



Leaves present, long - 10. C. diffusus. 



T^m 



« The specific name dmiainus is older and unoccupied. — Editor 



