1953] 



REVISION OF MACROLOBIUM 



289 



Tree to 20 m. tall, the branchlets and leaflets glabrous. Petioles 8-12 mm. 

 long, canaliculate, glabrous or with a very few scattered hairs. Leaf blade oblong, 

 11-14-jugate, the pairs of leaflets 8-12 mm. apart; rachis 9.5-12 cm. long, glab- 

 rous or rarely with few scattered hairs on the upper surface of the wings. Leaflets 

 16-32 mm. long, 6-10 mm. wide, oval-oblong, the base inequilateral, the upper 

 side cordate, the lower obtuse, the apex rotund, slightly retuse, apiculate mi- 

 nutely, the costa impressed on the upper surface, salient beneath, the venules 

 prominulous. Inflorescence 4.5— 5 cm. long, 1-2 lateral branchlets frequently pres- 

 ent, the axis sparsely short-pilosulose, the peduncles 4-6 mm. long, glabrous or 

 very sparsely short-pilosulose; bracts 5 mm. long, 2.5 mm. wide, caducous, ovate, 

 acute, glabrous except for the ciliolate margins; pedicels 3 mm. long, very sparsely 

 short-pilosulose; bracteoles 7 mm. long, 3.5 mm. wide, oblong-obovate, abruptly 

 acute, glabrous except for a few hairs at the apex. Hypanthium 2 mm. long, ses- 

 sile, glabrous. Sepals five, the adaxial pair nearly completely united, 4.5*5 mm. 

 long, 1-1.5 mm. wide, linear-oblong. Petal blade 4.5 mm. long, 6 mm. wide, trans- 

 versely oval, the claw 5 mm. long, auriculate, glabrous. Filaments 16.5 mm. long, 

 glabrous. Stigma capitellate. Style over 16.5 mm. long, glabrous. Ovary 2.5 mm. 

 long, 1 mm. wide, oval-oblong, 2-ovulate, glabrous, the gynophore about 1.5 mm. 

 long, sparsely pilosulose, inserted midway on the adaxial wall of the hypanthium. 

 Fruit unknown. 



Type Collection: A. Ducke 1394 (H.J.B.R. No. 50738), M B6a Vista, Rio 

 Branco,"Amazonas, Brazil, Aug. 1943 (HOLOTYPE RB, isotypes A, F, IAN, NY, 

 US). Known only by the type collection. 



The affinity of M. furcatum for M. flexuosum, and in particular for var. parvi- 

 florum of the latter species, is quite clear. It differs from M. flexuosum by its 

 glabrous bracteoles and filaments, and it may be further distinguished from var. 

 parviflorum by the outline and length of the leaf blades and by the size and pu- 

 bescence of the bracts. 



13. Macrolobium molle (Benth.) Cowan, comb. nov. Figure 5a. 



Macrolobium flexuosum Spruce ex Benth. var. molle Benth. in Mart. Fl. Bras. 15(2): 

 223- 1870. 



Tree 8-18 m. tall, to 38 cm. in diameter, the branchlets densely pilose. Stip- 

 ules 5-19 mm. long, 1-2 mm. wide, caducous, subulate or falcate-linear, acumi- 

 nate, densely papillose-puberulous on the inner surface, densely pilosulose out- 

 side. Petioles 7-15 mm. long, sulcate at the apex. Leaf blades oblong or oval- 

 oblong, 4-10-jugate, the pairs of leaflets 6-20 mm. apart; rachis (4-)5(-10.5) cm. 

 long, puberulous on the upper surface, pilosulose beneath. Leaflets (20-)30(-63) 

 mm. long, (8-)12(-23) mm. wide, oblong, the base inequilateral, the upper side 

 subcordate to cordate, the lower side acute to subobtuse, the apex rotund, entire 

 to retuse, sometimes minutely apiculate; upper surface velvety-puberulous, punc- 

 tate and densely beneath, the lateral surfaces of the costa more densely pubes- 

 cent than blade; costa plane to subimpressed on the upper surface, salient be- 

 neath, the venules usually obscure, sometimes subprominulous. Inflorescence 3* 

 8.5 cm. long, the axis pilosulose, the peduncle 9-23 mm. long; bracts 1.5 mm. 

 long, 0.5 mm. wide, early caducous, triangular, acute, ciliolate, strigulose on the 

 inner surface, pilosulose externally; pedicels 2-4 mm. long, pilosulose; bracte- 

 oles 6 mm. long, 3*3.5 mm. wide, elliptic or oval-elliptic, pilosulose. Hypanthium 

 1 mm. long, glabrous, sessile. Sepals five, the adaxial pair partly united, 1.5*3 

 mm. long, 0.5*2 mm. wide, lanceolate, acuminate to caudate-acuminate, ciliolate 

 apically. Petal blade 3-4.5 mm. long, 3.5*5 mm. wide, transversely oval, glabrous 

 externally, villose on the inner surface up to and over the center, the claw 2.5-3.5 

 mm. long, auriculate, ciliolate at the base, more or less villosulose on the inner 



