1958] 



THE BOTAXY OF THE QUAY AN A HIGHLAND PART III 



137 



locally occasional in tree " island" in Savanna No. 3, northwest base of Cerro Yapacana, elev. 

 150 m, Mar 17, 1953. 



The fruit of this species is now known. The follicle is 8 cm long, about 4 mm 

 broad; seeds brown, elliptic-lanceolate, short-beaked at the apex, 1.5 cm long, 

 2.7 mm broad, glabrous (microscopically papillose), rugolose. The seeds appear 

 to be ecomose ; no coma was found within the follicle ! The calyx-lobes are up 

 to 2 mm long. 



Paralyxia macrophylla (Muell.-Arg.) Mgf. Figure 15. 



Forest Department of British Guiana Field No. Guppy 479, Record No. 7494, headwaters 

 of Rio Trombetas, Brazil, at the British Guiana frontier, Uranwau, riverside, alt. 1000 ft, 

 Oct 22, 1952, semi-prostrate tree with three stems, 8" X 40', pale yellowish bark, pale yellow 

 slash and wood, white milk, leaves light green, arranged in a spiral near twig ends, flowers 

 white, in subterminnl axillary cymes, fruit flat, ear shaped, 2" long. 



The monotypic genus Paralyxia has until now been represented in herbaria 

 only by the Schomburgk t}-pe collection made over a hundred years ago on the 

 Tenette hills by the river Takutu in British Guiana. The affinity of this genus 

 has been under discussion (Markgraf, Notizbl. 13: 456-59. 1937). Fortunately, 

 the fruit has now for the first time become available ; it suggests a strong link 

 with Aspidosperma, the genus under which the species was originally described. 

 The single mericarp I have before me is a dry dehiscent compressed follicle, 

 almost circular in shape, broadly reniform or ear-shaped, 4.7 cm long, 4 cm wide, 

 3-6 mm thick, smooth and glabrous; its shallow sinus is about 12 mm across; 

 the curved ridge, which arches over the sinus forming a crescent area on each 

 valve, is 5 mm from the margin at its widest point. The seeds are 4 in number, 

 orbicular, 3.5 cm in diameter, very thin but not papery-winged; the embryo is 

 eentrally located, the funiculus is 1.7 long; the cotyledons are coated by a mem- 

 branous-thin endosperm, orbicular, about 15 mm in diameter, cordate with an 

 open sinus at their base; the radicle is oblong-ellipsoid, about 3 mm long, 1.3 

 mm thick, slightly surpassing the lobes of the cotyledons. The fruit and seeds 

 are not essentially different from those of Aspidosperma. The flowers also are 

 similar to those of that genus. They do not have, however, the clefts behind the 

 anthers described for Aspidosperma by Woodson (Ann. Missouri Bot. Gar. 38: 

 124—125. 1951) and suggested as "a rather precise morphological criterion to 

 separate" it from other closely related genera. G. Erdtman examined the pollen 

 grains of 479 and reported that they seem to be very similar to those of Aspido- 

 sperma cylindrocarpon, the only species of Aspidosperma in his collection. 



Prestonia acutifilia (Benth. ex Muell.-Arg.) K. Sch. 



Colombia: Maguire $ WurdacTc 34991, Rio Negro, along river between Piedra Cucuy 

 and Santa Rosa, elev. 100 m, Apr 11, 1953, woody vine, flowers pale yellow. VENEZUELA: 

 Amazonas: Maguire, WurdacTc 4' Bunting 36101, Great Rapids of the Orinoco, in low moist 

 savanna near Palomal, near river 15 km south of Pto. Ayacucho, 100-120 m elev., Nov 9, 

 1953, vine in low shrubs, flowers sulphur yellow. Maguire, WurdacTc 4' Bunting 37529, Casi- 

 quiare, occasional along Rio Yatua near Laja Catipan, 100-140 m, Feb 6, 1954, vine climbing 

 on low trees, flowers sulphur yellow, the throat ring whitish with 5 orange bars. Bolivar: 

 Wurdack $ Monachino 39870, Rio Orinoco, occasional in Isla Sta. Elena, opposite mouth of 

 Rio Pargueni, elev. 80-90 m, Dec 13, 1955, plant without latex, flowers pale yellow. WurdacTc 

 $■ Monachino 39976 Rio Orinoco, Laja Caruto, east bank of river just below Raudal Marimare, 

 elev. 80-90 m, Dec 18, 1955, herbaceous vine on shrubs, latex none, corolla pale greenish 

 yellow. BRAZIL: Cowan 38279, Serra do Navio, Amapa, Rio Amapari, forested slopes of 

 Observatorio Ore Body, ca. 275 m alt., Nov 12, 1954, vine over secondary growth, flowers pale 

 yelloAv, fruit green. 



