244 MAGUIRE 



submitted to the U.S. National Herbarium. Personal collections of the many 

 participants are at many botanical institutions of this country. 



The Rubber Program. During the war period, because rubber supply 

 from the Far East had been cut off, a comprehensive program was pursued 

 by the Division of Rubber Plant Investigation, Bureau of Plant Industry, at 

 Washington, to locate in the field and obtain material for the selection of high- 

 yield and disease-resistance strains and to obtain data and specimens for the 

 taxonomic study of Hevea and related genera. 



Prominently concerned in the field program were John T. Baldwin, R. J. 

 Seibert (1940-1946), and Richard E. Schultes, who did field work in the 

 Amazon Basin almost continuously from 1941 to 1953. 



In addition to specimens collected for the specific purposes of the program, 

 including those for detailed taxonomic study of Hevea, Mkrandra, etc., an 

 enormous amount of general material was collected which, now that the ur- 

 gency of the rubber program has receded, may in all probability come to be 

 the most important result of the undertaking. 



In his thirteen years in the hylean region of the Amazon Basin (1941- 

 1942, under the auspices of the National Research Council, 1943-1953, for 

 the U.S.D.A.), Schultes obtained approximately 23,000 collection numbers 

 mostly of vascular plants as follows: 1941-1946, in Colombian Amazonas; 

 1947-1948, in Brazilian Amazonas (three months in 1945 in Peruvian Ama- 

 zonas) ; and 1948-1953, again in Colombian Amazonas. The first set of these 

 important collections is at Washington. 



Schultes has thus spent a longer period of time in the hylean region than 

 did his illustrious predecessor and mentor Richard Spruce. He has collected 

 again many of the species known only from Spruce specimens and has himself 

 discovered large numbers of ''new" species. He has especially contributed im- 

 portant materials and geographical data pertaining to the region of the Ro- 

 raima sandstone sediments of Colombian Amazonas. 



The Guayana Highland Program of The New York Botanical 

 Garden. This long-term project, supported in part by the National Science 

 Foundation, unlike the preceding four, has been carried on primarily by the 

 staff of a single institution. The New York Botanical Garden since 1928 has 

 been concerned with the exploration and tloristic study of the Guayana High- 

 land of southern Venezuela and contiguous British Guiana and Brazil. This 

 is a region characterized topographically by great and small, lofty, more or 

 less isolated sandstone, tabular mountains, separated, except in the Gran 

 Sabana in Venezuela and parts of Colombian Amazonas, by valleys and river- 

 drainage basins supporting low-altitude rain forest. Geologically, these tabular 

 mountains are the erosion remnants of a series of sand and volcanic sediments 

 collectively known as the Roraima Formation and presumably were laid down 

 in Cretaceous time. 



Historically, botanical exploration of the Guayana Highland began with 



