318 



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



ad basim ciliolata et extus pilosula, intus pilosa in unguicilo. Filamenta 11.5- 

 15.5 mm. longa, ad basim villosa. Stigma capitellatum. Stylus 17.5 mm. longus, ad 

 basim puberulus. Ovarium 2 mm. longum, 1 mm. latum, oblongum, puberulum, 2- 

 ovulatum, gynophoro 2 mm. longo, puberulo. Fructus (senes valvae solum) circa 

 10.5 cm. longus, 4 cm. latus, oblongus, alis angustis, carpophorum 8 mm. longum, 

 minute puberulum. Semina 2.5 cm. longa, 2 cm. lata, ovalia, plana, testa tenui- 

 coriacea, plus minusve venosa. 



Type Collection: A, Ducke 15605, "chemin de fer d'Alcobaca, Tocantins, 

 Campina d'Arumateua," State of Para, Brazil, Jan. 1915 (HOLOTYPE US, iso- 

 type G). Known only by the type collection. 



It is with the greatest pleasure that this species is named for Dr. Adolpho 

 Ducke, who has contributed so richly to the knowledge of the flora of northeastern 

 South America by his extensive collections and voluminous writings. He has de- 

 scribed a large number of species of Macrolobium and his synopsis of the genus 

 in the Amazonian Hyalea was quite well done. It is fitting, then, that his name be 

 perpetuated in a species of a genus to which he has given so much of his time 

 and energy. 



The collection cited was identified as M. bifolium when received for this 

 study. While this is the closest relative of the new species, the latter is readily 

 recognizable by the rotund-auriculate lower side of the leaflet base, its puberu- 

 lous rather than papillate-puberulous ovary, its transversely oval petal blade, and 

 its minutely puberulous rather than papillate-puberulous fruit. 



32. Macrolobium amplexans (Amshoff) Cowan, comb. nov. Figure 11. 



Macrolobium bifolium (Aubl.) Pers. var. amplexans Amsh. Bull. Torrey Club 75: 388. 

 1948. 



Tree to 40 m. tall, 1 m. in diameter, the branchlets very minutely puberulous. 

 Petioles 8-13 mm. long, canaliculate, very minutely puberulous. Leaflets 8.5-17 

 cm. long, 3-7.5 cm. wide, arcuate, oblong-elliptic, the base inequilateral, acute, 

 the lower side decurrent, the apex truncate-acute, epunctate, minutely puberulous 

 at the base on the upper surface, glabrous beneath; costa plane above, salient be- 

 neath, the venules prominulous above, prominent beneath. Inflorescences 3.5-7 

 cm. long, ramiflorous, the axis minutely puberulous, the peduncles about 2 mm. 

 long; bracts 1 mm. long and wide, triangular, ciliolate, glabrous on the inner sur- 

 face, minutely puberulous externally; pedicels 2-5 mm. long; bracteoles 6 mm. 

 long, 4 mm. wide, oblong-oval, slightly apiculate, glabrous within, minutely pu- 

 berulous externally. Hypanthium 1.5 mm. long, glabrous. Sepals four, 3"4 mm. 

 long, 2.5 mm. wide, oval to oblong, obtuse, glabrous. Petal blade 6 mm. long, 7 

 mm. wide, about orbicular, the claw 4 mm. long, very strongly auriculate basally, 

 the auricles pilosulose externally and ciliolate, villose within on the claw and up 

 to the center of the blade. Filaments villose over most of the surface. Stigma 

 peltate. Style about 15 mm. long, very minutely puberulous basally. Ovary 3 mm. 

 long, 1.5 mm. wide, oblong, minutely puberulous on all surfaces, 2-ovulate, the 

 gynophore 3 mm. long, minutely puberulous, inserted midway on the adaxial wall 

 of the hypanthium. Fruit unknown. 



Type Collection: B, Maguire 24308, "high bush north of Savanna I, Tafelberg, 

 Surinam," Aug. 1944 (HOLOTYPE NY, isotypes F, G, MO, U, US). Known only by 

 the type collection. 



Miss Amshoff in describing this group as a variety of M. bifolium was certainly 

 not far afield, for in many respects obvious similarities do exist. However, it is 

 held that there are ample characters of sufficient magnitude and importance for its 

 elevation to specific rank. 



