i 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



[VOL. 10 



Arthrostylidium scandens McClure, sp. nov. 



Culmi "scandentes, usque ad 8-metrales, " internodiis . . . nodis . . . vagi- 

 nis (omnibus desideratis) ; rami (partes incompletae tantum ramulas ferentes 

 suppetunt) elongati, graciles, semel ramosi, internodiis glabris nitidisque ; foli- 

 orum vaginae crassae, supra medium nervoso-striatae carinataeque, glabrae vel 

 glabrescentes. auriculis subobsoletis, setis oralibus crebris, erassis, pallidis, 

 glabris vel asperulis, usque ad 10 mm longis, apice gracillimis fragilisque demum 

 diffractis, ligula interior brevissima vulgo non exserta, ligula exterior glabra, 

 nitida, apiee emarginata vel undulans, margine integra vel minutissime cili- 

 olata ; foliorum laminae usque ad 18 cm longae et usque ad 35 mm latae, lance- 

 olatae vel oblongo-laneeolatae, apicem versus obtusulum subito acuminatae basi 

 in petiolum crassum usque ad 8 mm longum omnino glabrum inaequaliter ro- 

 tundatae, paginis utrisque dempto apiee hispidulo glabrae, eosta subtus tantum 

 basin versus manifesta, nervis secundariis tertiariis vix distinguendis, venulis 

 transversis non manifestis. 



Inflorescentia vel axillaris vel ramos foliiferos terminans subspicato-racemosa, 

 pedunculo vix exserto, rhachi usque ad 30 cm longa graeili, omnino glabra, pas- 

 sim papillulosa, tereti, supra insertionem pedieellorum sulcata, bracteis pedi- 

 cellos subtendentibus minutis vel obsoletis, pedicellis rarissime approximatis 

 vulgo 2-3 cm sese distantibus, plerisque ca. 0.5 mm longis nonnullis brevioribus, 

 semicylindratis adpressis, bicarinatis, carinis c-iliolatis alibi glabris; spiculae 

 antrorsae, juveniles teretes arctaeque, maturitate compressiusculae hiantesque, 

 mox diffractae pleraeque 5-flores, floscula suprema ad lemma sterile valide in- 

 volutum subsetiforme reducta ; rachillae segmentis compresso-clavatis omnino 

 glabris nitidisque, inferioribus, non medium paleae attingentibus, superioribus 

 medium paleae excedentibus, infra lemmata et supra glumam superiorem disarti- 

 culantibus, glumis vacuis vulgo 2, approximatis persistentibus, lanceolatis, hispidu- 

 lis vel subglabris, pallide stramineis, papyraceis, fragilibus, subaequalibus 5-6 mm 

 longis, carinatis, apice mucronatis ; lemma 7-10 mm (rarissime 13 mm) longum, 

 viridi-stramineum purpura pictum, paulum indurate papyraeeum fragile (fis- 

 sile), apicem versus acutum submucronatum carinatumque alibi nervibus sub- 

 mersis plurinerve, dorso omnino glabrum vel superne hispidulum, intus apicem 

 versus minute albo-strigosum ; palea lemma aequans vel superans, membranacea, 

 apice comoso obtusa, sulco hispidula, extra carinas glabra invalide paucinervis- 

 que, carinis setosula vel glabra ; lodiculae 3, hyalinae, enerves, apice parce cilio- 

 latae alifei glabrae, ca. 2 mm longae, diversiformes, anteriores spathulatae, inae- 

 qualiter ovato-lanceolatae apice subobtusae, posterior lanceolata ; antherae 5.5-6 

 mm longae primo reticulato-virides brunneo pictae demum pallide brunneae, basi 

 hastatae utrinque apiculatae ; apice cornibus 2 brevibus approximatis angus- 

 tatae, connectivo supra haud producto ; ovarium pallidum glabrum ; stylus al- 

 bidus glaber solitarius, supra divisus in stigmatibus 2 dendriformibus, ramis 

 Longis gracillimis iterum ramosis. Fructus maturus desideratus. 



Type. Locally frequent along stream in moist forest, alt. 600-800 m, below 

 Camp II, Cerro Huachamaeari, Rio Cunucunuma, 20 Dec 1950, Amazonas, 

 Venezuela, Bassett Maguire, *R. S. Cowan & John J. Wurdack 29957 (holotype 

 US, isotype NY). 



The habit of the plant and the nature of the stigmas place this species near 

 A. e.ccelsum Grisebach, which differs most obviously in the inferior length and 

 diameter and the zigzag habit of the inflorescence axis, the more delicate leaf- 

 sheaths and the narrower leaf-blades. 



