Contents 



Abstract 



\ 



Page 



Introduction 1 



Endangered Species Act 1 



Definitions 2 



Previous Work 3 



Committee Report 3 



Lists of Trees of Puerto Rico and the Virgin Islands 4 



1 . Extinct Species 4 



2. Rare Endemic Species Needing Additional Protection 5 



3. Rare Endemic Species To Be Watched 6 



4. Other Rare Endemic Species 7 



5 . Common Endemic Species 8 



6. Rare Species Native Beyond (Nonendemic) 10 



Endemic Species of Virgin Islands 13 



Relationships of the Endemic Species 15 



Species New to Science 15 



Endemic Genera 15 



Trees Absent From Puerto Rico 16 



Public Forests and Parks 18 



Economic Importance of Endemic Species 19 



Puerto Rico and Hawaii Compared 20 



Discussion 23 



Summary 24 



Literature Cited 25 



Index of Scientific Names 26 



Little, Elbert L., Jr., and Roy O. Woodbury. 



1980. Rare and endemic trees of Puerto Rico and the Virgin Islands. U.S. 

 Dep. Agric, Conserv. Res. Rep. 27, 26 p. 

 CQ° Puerto Rico and the Virgin Islands together have about 55 1 species of native trees, 

 of which 539 are founcTin Puerto Rico. More than one-fourth, or 142, are known 

 only from these islands (endemic). Only about 13 rare endemic tree species need ad- 

 ditional protection and have been proposed as endangered. Also, 22 are to be 

 watched or monitored and have been proposed as threatened. About 100 others 

 listed as rare are native also beyond (nonendemic). The economic possibilities of 

 endemic tree species merit special attention, u 



OXFORD: 174(729.5); 181.1; 907.2. 



KEY WORDS: Trees (Puerto Rico); trees (Virgin Islands); rare trees; rare and endangered plants; tree 



sanctuaries. 



F— 529671 



Cover: Violeta, violet-tree, Polygala cowellii (Britton) Blake, at Juana Diaz. 

 Small to medium-sized tree scattered in forests of hillsides and arroyos. Native only 

 in Puerto Rico and classed as a rare endemic species to be watched. Beautiful masses 

 of violet-colored flowers cover the tree from February to March or April, generally 

 when leafless. Photograph by Frank H. Wadsworth. 



