1953} 



BOTANY OF THE GUAYANA HIGHLAND 



135 



TYPE: on granite rocks at low altitudes, Rio Cuao between Cerro Sipapo 

 and the Orinoco River, Amazonas, Venezuela, Bassett Maguire & Louis Politi 

 29027; New York Botanical Garden. Even when fresh, the leaves cannot be un- 

 folded without tearing. 



The four known species may be distinguished by the following key: 



Stem bearing stiff setae at each leaf-bearing node; leaves acute, tipped 

 with a short stiff spine; hypanthium glandular-hirsute. 

 Seeds with firm opaque wing; long and short shoots well differentiated; 

 leaf-blades 1—3 cm. long; plants growing on granite at low altitudes. 



Seeds with very thin hyaline wing; all internodes very short; leaf-blades 

 up to 13 mm. long; plants growing on sandstone at high altitudes. 



Stem without nodal setae; both long and short shoots developed; leaves 

 broadly rounded at the summit, not setose-tipped; hypanthium ap- 

 parently glabrous; plants growing on granite. 

 Leaves flat, spatulate to obovate-oblong; seeds 5-7 mm. long. A. pulchra. 



Leaves permanently folded, very broadly obovate-oblong; seeds 4-5 mm. 



long. A. plicata. 



Graffenrieda cinnoides Gl., sp. nov. 



Frutex pubescens; folia longe petiolata, ovato-oblonga, 5-pli-nervia, sub- 

 acuminata, basi obtusa, supra glabra subtus venis pubescentia, pagina grisea ato- 

 mis nitentibus; flores 4-5-meri, breviter pedicellati in panicula parva; sepala 

 triangulari-acuminata. 



Sparsely branched shrub. Stem thinly but closely brown-tomentulose with 

 stout, crooked, barbellate hairs; similar pubescence of the petioles (15-28 mm. 

 long) and the primary veins of the leaves. Leaves thin, ovate-lanceolate, sub- 

 acuminate to a blunt point, entire, obtuse at base, 5-pli-nerved, glabrous above, 

 sparsely pubescent on the primaries beneath, the actual surface grayish with 

 minute shining particles. Flowers 5-merous, in 3-flowered clusters, on pedicels 

 about 1 mm. long, forming a small loose panicle about 5 cm. long. Fruiting hy- 

 panthium 2.6 mm. long, closely dotted with minute shining particles. Sepals 

 separate to the torus, thin, triangular-acuminate, 1.4-1.8 mm. long and about as 

 wide. Petals lacking. Filaments about 4.3 mm. long; anthers subulate, arcuate, 

 about 3.5 mm. long; connective prolonged into a minute erect spur. Capsule 2-3- 

 celled. 



TYPE: summit of Cerro Sipapo, Bassett Maguire & Louis Politi 28180; New 

 York Botanical Garden. The plant has a strong habital resemblance to G. cinna 

 Macbr., a plant of low altitudes in Peru, but differs in the nearly glabrous leaves 

 and sessile flowers. 



Graffenrieda fantastica Schultes & Smith. 



Summit of Cerro Sipapo, Maguire & Politi 27542, Maguire & Politi 27782; 

 otherwise known only from the type locality on Mount Chiribiquete, Colombia. 



Graffenrieda pedunculata Gl., sp nov. 



Frutex, caulibus tumidis glabris; folia oblongo-lanceolata vel oblongo- 

 oblanceolata, obtusa, basi angustata, 1-nervia, supra glabra, subtus argentea; 

 pedunculus elongatus; flores 4-meri sessiles; calyx calyptriformis, circumscis- 

 sus; petala magna. 



Low branching shrub with thick stems and short internodes, each branch bear- 

 ing 2 or 3 pairs of leaves near the summit. Petioles up to 8 mm. long. Blades 

 firm, oblong-lanceolate to oblong-oblanceolate, up to 6.5 cm. long and 1.5 cm. 

 wide, obtuse, entire, gradually tapering to the base, 1-nerved, above glabrous, 



A. conferta. 

 A. montana. 



