1958] 



THE BOTANY OF THE GUAYANA HIGHLAND PART III 



29 



Herbae parvae foliis linearibus equitantibus basilaribus. pedunculis subter- 

 minalibus solitariis. Genus monotypicum. 

 Typus: Phelpsiella ptericaulis Maguire. 



Dr. William H. Phelps, Mr. William H. Phelps, Jr., and Kathleen D. Phelps 

 (Mrs. \Y. H. Phelps, Jr.) are all internationally known ornithologists and 

 natural historians. In 1937 the elder Phelps organized and sponsored the history- 

 making expedition to Auyan-tepui, ably led by G. H. H. Tate of the American 

 Museum of Natural History, the plants of which came to The Xew York Botani- 

 cal Garden. Before the exploration of Auyan-tepui and continuously since, the 

 Phelps have sent out and have themselves conducted ornithological expeditions 

 to all parts of Venezuela, particularly to Guayana. On most of these explorations 

 Kathleen Phelps in addition to her other duties has collected much critical plant 

 material from equally critical localities. On the expedition to Cerro Paru. Kath- 

 leen Phelps with C. H. Hitchcock, now Director of The American Geographical 

 Society, obtained the type material upon which Phelpsiella is based. It is emi- 

 nently fitting that our extraordinary new genus should bear the Phelps' name. 



Phelpsiella ptericaulis Maguire. sp. nov. 



Herbae perennes parvae ; caudicibus succulentis brevissimis erectis ; vaginis 

 18-25 cm longis, distich is. plus minusve equitantibus marcescentibus, basi sub- 

 bnlbosa, submembranaceis subtiliter nervato-striatis, auriculis prominentibus 

 erectis ovatis 7-8 mm longis. ca. 8 mm latis, basi obliqua ; laminis linearibus 

 subcoriaceis, 40-45 cm longis, 8-16 mm latis, aeutiusculis, nervis 11-13, infra 

 prominulis subtus prominentibus, minute punctatis; pedunculo solitario sub- 

 terminali valde acnteque compresso, 20-30 cm longo, 3-5 mm lato, apicem versus 

 late alato, 10-12 mm lato ; bracteis bivalvatis. spathaceis orbiculari-obovatis vel 

 oblongis rotundatis, 12-20 mm longis, 12-14 mm latis, apicem versus recurvatis, 

 extus absolutis, intus prominentibus, 5-7-nervatis ; spiculis 2-4. scssilibus, brac- 

 teolis 13-14, oblongo-lanceolatis obtusis apice crassatis, gradatis enervatis, ex- 

 terioribus 6-7 mm longis, ca. 4 mm latis, interioribus 9-10 mm longis, ca. 3 mm 

 latis; sepalis lanceolatis obtusis, 12-14 mm longis, indurato-chartaceis. 7-nervatis. 

 ad basim membranaceis 3—4 mm. eonnatis per 0.5-1.0 mm, marginibus deorsum 

 ab apice late membranaceis; petalis 2.0-2.5 cm longis, oblanceolatis rotundatis 

 breviacuminatis. ca. 4.5 mm latis, unguibus 3-4 mm longis, per 2-3 mm eonnatis ; 

 filamentis ca. 5 mm longis, tubo corollae affixis; antheris bithecatis, 4-lobatis, ad 

 apices biporis, ca. 8 mm longis ; ovario 3-loculari, loculis pluriovulatis ; seminibus 

 subprismaticis,, 1.5-3.0 mm latis, 1.75-2.0 mm longis, rufo-bruneis, testa exteriore 

 scariosa valde alveolata. 



Type : small herb with yellow flowers, very abundant, mostly in open areas, 

 summit Cerro Paru at 1600 m alt., Feb 11, 1949, Terr. Amazonas, Venezuela, 

 Phelps d: Hitchcock 518 (holotype XY). Paratypes : Cerro Paru, 2000 m alt., 

 Cowan & Wurclack in 1951 : Jan 31, 31058; Feb 2, 31172; Feb 4, 31251; Feb 7. 

 31373, 31352. 



Known only from the Serrania Paru, where it appears to be common. The 

 collectors note that rootstocks develop offshoots and apparently form colonies by 

 vegetative multiplication. The leaves are described as appearing blue by reflected 

 light, a phenomenon often observed in the Rapateaceae. 



Phelpsiella is a monotypic reductive genus, possibly most nearly related to 

 Amphiphyllum . 



