PREFACE. 



The present paper is the third of Mr. Pittier's series under the title 

 "New or Noteworthy Plants from Colombia and Central America." 

 An imperfectly known group of the mulberry family is revised, with 

 the addition of three new species, and new species are described and 

 old ones discussed in several other families. A large part of the 

 species are trees, some of them of economic value. The results 

 offered are based on actual field work by Mr. Pittier. 



Frederick V. Coville, 

 Curator of the United States National Herbarium. 



