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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [Vol. 8, No. 4 



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Vuapa taxifolia (Spruce ex Benth.) Kuntze, Rev. Gen. 1: 213. 1891. 



Tree 5-7 m. tall, the branchlets pilosutose. Stipules 15 mm. long, 2.5 mm. 

 wide, subfalcate-linear, ciliolate. Petioles 6 mm. long, canaliculate, pilosulose. 

 Leaf blades oblong-lanceolate, 36-42-jugate, the pairs of leaflets about 3 mm. 

 apart; rachis 8.5-13 cm. long, pilosulose except on the lower surface of the nar- 

 row wings. Leaflets 5-20 mm. long, 1-3 mm. wide, linear, the base inequilateral, 

 obtuse, the apex rotund, minutely apiculate, the upper surface convex, glabrous, 

 nitid, the lower surface glabrous or the costa with very few hairs, the costa plane 

 on the upper surface, salient beneath, the venules obscure. Inflorescence 6.5-8 

 cm. long, the axis pilosulose, the peduncle 3*4 mm. long; bracts 5.5 mm. long, 

 4.5 mm. wide, broadly oval, pilosulose, more strongly so externally; pedicels 2.5- 

 3 mm. long, pilosulose; bracteoles 7 mm. long, 4 mm. wide, obovate or oval, 

 bluntly acute, pilosulose externally and in the basal half within. Hypanthium 3- 

 3.5 mm. long, glabrous, the stipe o 5-l mm. long, puberulous. Sepals four, equal, 

 5.5 mm. long, 1.5-2.5 mm. wide, oblong, fleshy-coriaceous, sparsely ciliolate 

 near the apex. Petal blade about 6 mm. long, 4 mm. wide, orbicular, decurrent on 

 the 4 mm. long claw, glabrous. Filaments 21.5 mm. long, glabrous. Stigma simple. 

 Style 20 mm. long, glabrous. Ovary 3.5 mm. long, 1.5 mm. wide, oblong, glabrous 

 or with very few hairs on abaxial margin, 3-ovulate; gynophore 2.5 mm. long, pi- 

 losulose sparingly, inserted at top of the adaxial wall of the hypanthium. Fruit 

 unknown. 



Type Collection: R. Spruce 3566, "In Guainia ripis," supra ostium flum. Casi- 

 quiari, Venezuela, May-June 1854 (HOLOTYPE K, isotypes G, GH, NY, P, US- 

 frag., W). Known only from the type collection. 



Macrolobium taxi folium is placed at the beginning of this treatment because it 

 appears to be the nearest living relative to the ancestral stock, which, hypotheti- 

 cally, gave rise to the two principal divergent lines within the genus. Actually, it 

 lies about midway between the two sections, but in its more important characters 

 appears to be more closely associated with the species of section Vouapa. 



If the characters of M. taxi fo Hum are compared with those separating the two 

 sections, the following will be apparent. It has a short-cylindric hypanthium which 

 is about twice as long as wide and is thus similar to that attained in the more 

 primitive groups of section Stenosolen. The bracteoles open completely on both 

 the adaxial and abaxial sides of the flower, thereby exhibiting a character of the 

 first section. The sepal number by itself is a character of secondary importance, 

 but here there are four equal sepals inserted on a short-cylindric hypanthium, in 

 this respect resembling more closely the second section than the first. The petal 

 possesses a long claw as in section Vouapa but it is not well-delimited from the 

 blade. 



This species is not at all closely related to any other known species; it may 

 be most easily distinguished by its 35-45-jugate leaves, the leaflets of which are 

 strongly convex on the upper surface, in addition to the diagnostic characters dis- 

 cussed above. 



2. Macrolobium gracile Spruce ex Benth. in Mart. Fl. Bras. 15(2): 223. 1870. Fig- 

 ure 3. 



Shrub or slender tree 4-20 m. tall, the branchlets pilosulose or pilose. Stipules 

 2-14 mm. long, 0.5-1 mm. wide, usually caducous, subulate-linear, linear, or 

 linear-lanceolate, pilosulose on the outer surface, glabrous within. Petioles 1.5- 

 6 mm. long, canaliculate, pilosulose. Leaf blades lanceolate, elliptic-oblong, or 

 lanceolate-oblong, 10-40-jugate, the pairs of leaflets 2-8 mm. apart; rachis 4-14 

 cm. long, pilosulose or uncinate-puberulous on the upper surface and pilosulose or 



