1953] 



REVISION OF MACROLOBIUM 



307 



costa or also on the primaries, punctate or epunctate beneath; costa and primaries 

 more or less impressed on the upper surface, salient beneath, the intramarginal 

 nerve usually strongly developed. Inflorescence 1.5-7 cm. long, several fascicu- 

 late in loose clusters or solitary, the axis minutely puberulous, sessile or the pe- 

 duncle to 2.5 mm. long; bracts 1-1.5 mm. long and wide, caducous, triangular, ob- 

 long, triangular-oblong or semicircular, ciliolate, glabrous within, minutely puber- 

 ulous externally, acute to obtuse; pedicels 1.5-4.5 mm. long; bracteoles 4.5-7.5 

 mm. long, 2.5-5 mm. wide, rotund, apiculate or mucronate, oblong, obovate, or ob- 

 long-obovate, concave, glabrous on the inner surface, minutely puberulous exter- 

 nally. Hypanthium 1-3.5 mm. long on a stipe 0.5-1.5 mm. long, glabrous. Sepals 

 four or five, 2-7 mm. long, 1-5 mm. wide, obtuse or acuminate, oblong, lanceolate, 

 triangular, or oval, ciliolate, glabrous within, glabrous to sparsely puberulous ex- 

 ternally. Petal blade 4.5-6.5 mm. long, 4-7 mm. wide, oval to orbicular, the claw 

 3-6.5 mm. long, auriculate or non-auriculate, glabrous externally or pilosulose at 

 the base, ciliolate in the lower part of the claw, villose within on the claw and 

 into the throat or to the center of the blade, or the blade glabrous. Filaments 15- 

 25 mm. long, more or less villose or villosulose basally, the anthers 1.5-2.5 mm. 

 long, 1-1.5 mm. wide. Stigma simple or capitellate. Style 12-18.5 mm. long, glab- 

 rous to sparsely puberulous basally. Ovary 1.5-2.5 mm. long, 1-1.5 mm. wide, 

 oval to oblong to elliptic, puberulous on the margins, glabrous on the lateral sur- 

 faces, rarely puberulous on all surfaces, 2-6-ovulate; gynophore 2-3.5 mm. long, 

 glabrous or minutely puberulous, inserted at the margin of the hypanthium. Fruit 

 10 cm. long, 6.5 cm. wide, obovate, glabrous, irregularly salient-venose, the ad- 

 axial margin with woody wings. 



Key to the Varieties of Macrolobium unijugum 



1. Costa and primary veins, including intramarginal vein, markedly impressed on upper 

 leaflet surface, leaflets punctate beneath; inflorescences 1.5-4.5 cm. long, several 

 fasciculate in loose clusters 25c. var. unijugum. 



1. Costa impressed but primaries not impressed on upper surface, leaflets epunctate be- 



neath; inflorescences 4.5-7 cm. long, borne singly or few together but not in loose 

 clusters 2. 



2. Sepals five, lanceolate, 2-3 mm. long; hypanthium 1 mm. long on 0.5 mm. stipe; apex of 



bracteoles apiculate; anthers 1.5 mm. long, oval; leaflets sessile. Northern British 



Guiana 2 5a. var. fanshawei. 



2. Sepals four, oblong, 6—6.5 mm. long; hypanthium about 2.5 mm. long on 1 mm. stipe; 

 apex of bracteoles mucronate; anthers 2.5 mm. long, oblong; leaflets sometimes with 

 petiolules to 3 mm. long. Northwesternmost Brazil 25b. var. mucronatum. 



25a. Macrolobium unijugum var. fanshawei Cowan, var. nov. Figure 8. 



Arbor 20 m. alta, 2 dm. diametro, ramulis glabris. Petiolus 12-15 mm. longus, 

 canaliculars, glaber. Foliola 12-18.5 cm. longa, 4.5-7 cm. lata, subaequila- 

 teralia, elliptica, ad basim inaequilateralia, acuta, ad apicem abrupte acuminata, 

 extremitate obtuso, glabra, epunctata, costa impressa supra, infra salienti, venu- 

 lis subobscuris supra, infra prominentibus. Inflorescentiae 5 cm. longae, soli- 

 tariae, axe minute puberulo, pedunculis 2-2.5 mm. longis; bracteis caducis; pedi- 

 cello 3*5-4 mm. longo, minute puberulo; bracteolis 6 mm. longis, 3 mm. latis, ob- 

 longis, apiculatis, intus glabris, extus minute puberulis. Hypanthium 1 mm. longum, 

 stipite 0.5 mm. longo, glabrum. Sepala quinque, 2-3 mm. longa, 1-1.5 mm. lata, 

 duobus adaxilibus triangularibus, acuminatis, 3 ceteris lanceolatis, acuminatis, 

 ad apicem ciliolatis. Petali lamina 5 mm. diametro, orbicularis, unguicilo 4 mm. 

 longo, exauriculato. Filamenta 17.5 mm. longa, basim versus sparse villosula, 

 antherae 1.5 mm. longae, 1 mm. latae. Stigma subpeltato-capitellatum. Stylus 15.5 

 mm. longus, glaber. Ovarium 2 mm. longum, 1 mm. latum, oblongum, solum mar- 



