2953] 



REVISION OF MACROLOBIUM 



275 



VEN); banks of Rio Cunucunuma above Playa Alta, Nov. 1950, Maguire, Cowan & Wurdack 

 29496 (F, NY), 29505 (NY, US, VEN); Culebra, Ri6 Cunucunuma, Dec. 1950, Maguire, 

 Cowan & Wurdack 30357 (K, NY, US), 30362 (B, BM, F, G, GH, IAN, K, LE, MO, NY, P, 

 RB, S, U, UC, US, VEN); Rio Cuao, Nov. 1948, Maguire & Politi 27383 (FHO, NY, TH, 

 WTU), 27447 (F, G, GH, IAN, K, MO, NY, P, RB, U, US, VEN); Rio Cuao, Jan. 1949, Ma- 

 guire & Politi 28526 (A, BPI, MICH, NY); forest along Cano Negro, southeastern base of 

 Cerro Duida, alt. 225 m., Aug. 1944, Steyermark 57940 (F, MO, VEN). 



2b. Macrolobium gracile var. machadoense Cowan, var. nov. Figure 3. 



Arbor 20 m. alta, 6 cm. diametro, ramulis dense pilosulis. Stipulae 4.5*5.5 mm. 

 longae, 0.5 mm. latae. Petiolus 2-3 mm. longus, canaliculatus, pilosulus. Foli- 

 orum lamina lanceolata, 20-25-jugata; rachibus 5.5-9 cm. longis, supra uncinato- 

 puberulis, infra sparse pilosulis ad glabris. Foliola 2-15 mm. longa, 1-5 mm. lata, 

 oblonga, ad basim inaequilateralia, ad apicem truncata, emarginata, minute apicu- 

 lata, supra in costa puberula, infra plus minusve pilosula, costa ambobus lateribus 

 salienti, venulis obscuris. Inflorescentiae 4.5-5 cm. longae, axe puberulo, flos 

 ignotus. Fructus immaturus 11-11.5 cm. longus, oblongus, apicem versus latior, 

 carpophoro 5 mm. longo, pilosulo. 



Type Collection: B. A. Krukoff 1350, "upper Machado River, near Tabajara," 

 Matto Grosso, Brazil, Nov, -Dec. 1931 (HOLOTYPE NY, isotypes A, F, G, MO, 

 P, U, UC). Known only from the type collection. 



2c. Macrolobium gracile var. debile (Ducke) Cowan, comb. nov. Figure 3. 



Macrolobium debile Ducke, Bull. Mus. Hist. Nat. Paris II. 4: 729. 1932. 



Shrub or small tree with pilosulose branchlets. Petioles 2-3 mm. long. Leaf 

 blades elliptic-oblong, (l6-)20-30-jugate, the pairs of leaflets 2-5 mm. apart; 

 rachis 5-14 cm. long, the wings ciliate, the axis pilosulose sparingly. Leaflets 

 5-20 mm. long, 1-5 mm. wide, linear, the upper side of the base subcordate, the 

 lower side obtuse, the apex rotund, entire, mucronate, the upper surface glabrous 

 or very sparsely puberulous on the blade, the costa sparsely puberulous at least 

 at the base, the lower surface glabrous to pilosulose on the costa and on the api- 

 cal half of the blade. Inflorescences 1-1.5 cm. long; bracts 2.5 mm. long, 1 mm. 

 wide, triangular-lanceolate; bracteoles elliptic, 5-6 mm. long, 2.5-3 mm. wide, 

 the outer surface puberulous, pilose within. Sepals 1.5-3 mm. long, 0.5-1.5 mm. 

 wide. Petal blade 3.5 mm. long, about 5 mm. wide, the claw 4.5-5 mm. long. Fila- 

 ments 17-19.5 mm. long. Style 18-19.5 mm. long, villosulose basally. Ovary ob- 

 long, villose marginally, the gynophore 2 mm. long, villosulose, inserted about 

 midway on the adaxial wall of the hypanthium. Fruit unknown. 



LECTOTYPE: A. Ducke 20318 (flowering portion), "ad Cachoeira do Mindu, 

 Manaos," Amazonas, Brazil, Oct. 1927 (deposited RB, isolectotypes F-frag., G, 

 P, U, US). The fruiting portion of this collection, collected in November of the 

 same year and in the same locality, appears to be somewhat intermediate between 

 var. debile and the typical variety, which it most closely resembles. It does 

 not have the entire, mucronate leaflet apices of var. debile and the distribution 

 of the pubescence is much nearer that of the typical form. A lectotype has been 

 chosen in this case because under the International Code of Botanical Nomencla- 

 ture it is not permissible that a type be composed of more than a single collection. 



Additional Specimens: BRAZIL: Amazonas: Cachoeira do Mindu, Manaos, Aug. 1935, 

 Ducke 14 (A, F, IAN, MO, NY, US); ad Cachoeira do Mindu, Manaos, Nov. 1927, Ducke 

 20318 (fruiting) (G, P, RB, U). 



2d. Macrolobium gracile var. gracile- Figure 3, 



Vouap a gracilis (Spruce ex Benth.) Taub. Bot. Centralbl. 47: 393. 1891. 

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

 Macrolobium tenue Ducke, Bol. Tec. Inst. Agron. Norte [Belem] 2: 13. 1944. 



