1961] 



BOTANY OF THE GUAYANA HIGHLANDS PART IV (2) 



79 



5. Leaflets inequilaterally acute, not rigidly coriaceous. Bracts 1-1.5 mm long, triangular 



or ovate. 33. .1/ suaveolens & vars 



6. Leaflets rounded-obtuse on the lower side of the base, strongly salient-venose and 

 thickly coriaceous. Stipules persistent, coriaceous-foliaceous. Bark of branchlets 

 exfoliating. 32'. 31. exfoliatum. 



6. Leaflets acute basally, chartaceous, the venation not strongly salient. Stipules 



caducous. Bark of branchlets not exfoliating. 32. 31. amplexans. 



Key to the Species of Series 2c 



1. Bracts ca. 5 mm long, 3 mm wide, never triangular, the bracteoles strigulose within, 

 densely puberulous to pilosulose externally. Ovary pilosulose marginally. 



29. 31. angustifolium. 



1. Bracts 1-1.5 mm long and wide, triangular, the bracteoles glabrous or minutely 

 puberulous externally. Ovary minutely puberulous marginally. 2. 



2. Inflorescence minutely puberulous; petal longer than the bracteoles, the blade 

 orbicular to oblate, the claw distinct. Bracteoles oval, elliptic or oblong, 5-6.5 mm 

 long, the hypanthium 1-2 mm long. 33. 31. suaveolens. 



2. Inflorescences glabrous; petal about as long as bracteoles, more or less spatulate, 

 without a distinct claw. Bracteoles oblong to lanceolate, 8-13.5 mm long, the 

 hypanthium 3-4 mm long. 38. 31. stenopetalum. 



Key to the Species of Series 2d 



1. Leaflets punctate beneath, acuminate. Bracts caducous; gynophore pilosulose on 



adaxial surface. 33. 31. suaveolens. 



1. Leaflets epunctate, acute. Bracts persistent and closely imbricate on the basal part 



of the inflorescence axis: gynophore glabrous. 34. .1/. parvifolium. 



Key to the Species of Series 2e 

 1. Leaves unifoHolate, the leaflets equilateral. Ovary pubescent. 



(37'. M. unifoliolatum) 2. 



1. Leaves with unijugate, inequilateral leaflets. Ovary glabrous. 3. 



2. Leaflets puberulous on the salient costa on the upper surface. Inflorescence 6.5-12 

 cm long, the bracts and bracteoles puberulous externally. Pedicels 4-9 mm long, 

 densely puberulous. 37'b. 31. unifoliolal urn var. schultesii. 



2. Leaflets glabrous, the costa impressed on the upper surface. Inflorescence shorter, 

 the bracts and bracteoles glabrous. Pedicels shorter, glabrous. 



37'a. 31. unifoliolatum var. unifoliolatum. 



3. Stipules and rachis rudiment persistent; hypanthium strongly zygomorphie. 

 Leaflets often punctate. Belem and the Amazon Delta Region to southern Amazonas, 

 Brazil. 37. 31. pendulum. 



3. Stipules and rachis rudiment caducous; hypanthium symmetric to asymmetric. Leaf- 

 lets epunctate. Eastern Peru, upper Rio Negro and southwestern Venezuela. 4. 



4. Filaments glabrous. Petioles 1.5-4 mm long; leaflets 1.5-5.5 cm long, 1-2.5 cm. 

 wide, the lower side of the base rounded. 36. 31. savannarum. 



4. Filaments pubescent toward the base. Petioles 7-18 mm long; leaflets larger, 



the base cuneate. 5. 



5. Leaflets always unijugate, 11.5-17 cm long, narrowly elliptic, the petioles 7-9 

 mm long. Inflorescence axis microscopically puberulous; pedicels 4-5 mm long; 

 bracteoles 6.5 mm long, 3 mm wide, minutely puberulous externally. Sepals 5-5.5 mm 

 long. Eastern Peru. 26. 31. Tclugii. 



5. Leaflets sometimes in part bijugate, 6.5-9.5 cm long, elliptic, the petioles 13-18 mm 

 long. Inflorescence axis glabrous, the pedicels 6-8 mm long, the bracteoles 10-11 mm 

 long, 5 mm wide, glabrous. Upper Rio Negro, Brazil. 35. 31. palustre. 



1. Macrolobium taxifolium Spruce ex Benth. 



VENEZUELA: Amazonas: along Rio Guainia between Comunidad and Santa Rita, 

 alt. 120 m, 8 Jul 1959, Wurdaclc $ Adderley 43350. 



