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



k 



NY-New York Botanical Garden, New York, New York. 

 P-Museum National d'Histoire Naturelle, Laboratoire de Phanerogamie, Paris, 

 France. 



RB-Seccao de Botanica Sistematica, Jardim Botanico do Rio de Janeiro, Rio 

 de Janeiro, Brazil. 



U-Botanisch Museum en Herbarium van de Rijksuniversiteit te Utrecht, Utrecht, 

 Netherlands. 



UC-University of California Herbarium, Berkeley, California. 

 US-Smithsonian Institution, U. S. National Museum, Washington, D. C. 

 VEN-Division de Botanica, Ministerio de Agricultura y Cria, Caracas, Venezuela. 

 W-Naturhistorisches Museum, Botanische Abteilung, Wien, Austria. 

 Y-Yale University School of Forestry, New Haven, Connecticut. 



The author is much indebted to the directors and curators of all these institu- 

 tions, from which specimens have been borrowed. He gratefully acknowledges the 

 invaluable assistance of the following persons: Dr. Bassett Maguire, under whose 

 direction this research was conducted and who contributed extensively with his 

 encouragement and suggestions; Dr. David D. Keck and Dr. D. P. Rogers, who 

 have contributed liberally of their time in the preparation of the manuscript and in 

 the evaluation of the botanical conclusions during the absence of Dr. Maguire in 

 South America; and Dr. H. W. Rickett, for kind assistance in editorial and biblio- 

 graphic matters. 



GENERIC RELATIONSHIPS 



The tribe Amherstieae, while pantropic in distribution, is best represented in 

 tropical South America and tropical West Africa. There are fewer genera of the 

 tribe in South America than in Africa and they bear little resemblance to Macrolo- 

 bium, whose closest relatives are certainly African. Macrolobium , as heretofore 

 circumscribed, appears to be most closely allied to the African genus Berlinia, 

 although the American species are strongly dissimilar, and the connection with 

 this genus is through the African species of the Macrolobium complex. The rela- 

 tionship with other members of the Amherstieae is even more remote. 



Although the geographical range of Macrolobium has always been considered 

 to include tropical West Africa, recent developments have modified this view, at 

 least for the writer. A letter from Dr. J. Leonard of Institut National pour l'fitude 

 Agronomique du Congo Beige, Brussels, explained that he was completing a study 

 of the African species of Macrolobium and he enclosed an impressive synopsis of 

 his conclusions in the form of keys, tables, descriptions, and sketches. He ex- 

 plained that he was segregating two new genera from the African material and that 

 he considered the remainder of the species under two subgenera of Macrolobium 

 with the American species as a third subgenus. He asked consideration of his 

 conclusions and especially that the characters be checked which he considered 

 as significant in separating his various taxa, since he was less familiar with the 

 American species. As I had not reviewed the African situation, I was pleased to 

 have this opportunity of examining his work. 



After careful examination of the differences involved, the following table of 

 significant characters separating the species of America and Africa was sub- 

 mitted to Dr. Leonard, the points arranged in descending order of importance: 



American Species African Species 



1. Petal one. 1. Petals (4-)5(-6). 



2. Staminodia usually absent. 2. Small stamens and/or staminodia 4-7. 



