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



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midway or at the margin of the adaxial wall. Fruit (immature to mature) 5.5-11.5 

 cm. long, 2.5-5 cm. wide, oblong, oblong-oblanceolate, or oblong-obovate, spar- 

 ingly to sparsely pilose or glabrous on the margins, the carpophores 4-16 mm. 

 long, sparingly pilose or pilosulose. Seeds 3.5 cm. long, 2.5 cm. wide, oval, the 

 testa membranous, venose. 



Key to the Varieties of Macrolobium gracile 



1. Inflorescences less than 2 cm. long 3. 



1. Inflorescences 2.5-6.5 cm. long 2. 



2. Apex of leaflets rotund, entire to refuse, usually much narrower than the base, the me- 



dian leaflets of mature leaves four to six times as long as wide, the costa plane to im- 

 pressed on upper surface; leaves oblong to oblong-lanceolate; mature fruit 5.5-8 cm. 

 long, 2.5-3 cm. wide 2a. var. confertum. 



2. Apex of leaflets truncate, strongly emarginate, not appreciably narrower than base, the 



median leaflets of mature leaves about two to three times as long as wide, the costa 

 salient on upper surface; leaves lanceolate; immature fruit 11-11.5 cm. long, 3.5 cm. 

 wide 2b. var. machadoense. 



3. Leaves 20-30-jugate; median leaflets of mature leaves four or more times as long as 



wide, glabrous, or sparsely pubescent on costa and base of blade, the apices distinctly 



mucronate 2c. var. debile. 



3. Leaves (10-)1 5(- 20)- jugate; median leaflets of mature leaves usually about three times 

 as long as wide, the upper surface usually pilosulose, the lower pilose, the apices 

 minutely apiculate 2d. var. gracile. 



2a. Macrolobium gracile var. confertum (Gieason) Cowan, comb. nov. Figure 3« 



Macrolobium confertum Gieason, Bull. Torrey Club 58: 371. 1931. 



Low tree with spreading, flat-topped crown, 5-7 m. tall, the branchlets densely 

 pilosulose. Stipules 6-14 mm. long, 1 mm. wide, caducous or persisting one sea- 

 son, acuminate. Petioles (2-)3(-6) mm. long. Leaf blades oblong to oblong-lan- 

 ceolate, (14-)18-30(-40)-jugate, the pairs of leaflets (3-)4(-6) mm. apart; rachis 

 (5-)8-10(-13.5) cm. long, pilosulose but sparingly so on the lower surface of the 

 narrow erect wings, densely so above. Leaflets (4-)6-15(-28) mm. long, (l-)2- 

 4(-6) mm. wide, linear, the base obtuse, the apex rotund to rotund-truncate, nar- 

 rowing toward the entire to retuse apex, minutely apiculate, glabrous or more often 

 sparsely to strongly puberulous on the costa on the upper surface, the hairs often 

 uncinate, beneath glabrous, or sparingly pilosulose on the costa, the hairs often 

 subappressed or appressed, the costa plane to impressed on the upper surface. In- 

 florescence (2.5-)3-5(-6.5) cm. long; bracts 2.5-3 mm. long, 1-2.5 mm. wide; 

 pedicels (l-)2(-3) mm. long; bracteoles (5.5-)6-7 mm. long, 2.5-4 mm. wide, ob- 

 long to lanceolate, acute to acuminate, puberulous externally, villosulose within, 

 at least in the upper half. Sepals 1.5-4.5 mm. long, 0.5-2 mm. wide, lanceolate, 

 acute to^ caudate-acuminate. Petal blade (3.5-)4(-7.5) mm. long, (3«5-)5(-8.5) mm. 

 wide, the claw (4-)5(-6) mm. long, the petal villosulose over the entire outer sur- 

 face or only at the base, villosulose within, sometimes sparsely so. Filaments 

 (l6-)20(-27.5) mm. long. Style 15.5-22 mm. long, villosulose basally. Ovary ob- 

 long, villose marginally; gynophore villosulose, inserted near the apex of the ad- 

 axial wall of the hypanthium. Fruit 5.5-8 cm. long, 2.5-3 cm. wide, oblong to ob- 

 long-obovate or oblong-oblanceolate, glabrous or with few scattered hairs on the 

 margins, the carpophores 4-6 mm. long, pilosulose. Seeds about 1.5 cm. long, 1 

 cm. wide, oval, the testa membranous, venose. 



Type Collection: G. H. H.*Tate 375, "slopes of Mt. Duida, 750'," Amazonas, 

 Venezuela, Nov. 1928 (HOLOTYPE NY). 



Additional Specimens: VENEZUELA: Cano Asisa near Serrania Paru, Feb. 1951, 

 Cowan & Wurdack 31523 (K, NY, US, VEN), 31526 (F, G, K, MO, NY, US, VEN); western 

 foothills Serra Imeri, near Salto de Hua, Nov.-Dec. 1930, Holt & Blake 482 (A, NY, US, 



