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upon the principal diseases of the cocoanut, banana, cocoa 

 and logwood. 



Dr. M. A. Howe, assistant curator, has continued his sys- 

 tematic study of the algae of North America, the results of 

 which have been published in brief articles. Some attention 

 has also been given to the determination of Hepaticae of 

 North America. A field examination of the algal flora of 

 southern Florida was made late in the year and a large 

 amount of valuable material added to the collections. Dr. 

 Howe has also made some experimental observations on the 

 introduction of forms from northerly districts to the waters of 

 Long Island Sound. 



Dr. H. H. Rusby, curator of the economic collections, has 

 made notable progress in his work upon the flora of western 

 and northern South America, and has also completed some 

 extensive bibliographical work upon economic plants. 



Miss A. M. Vail, librarian, has continued her critical 

 studies of the Asclepiadaceae, and described new species in 

 several genera of this family. 



Mr. George V. Nash, head gardener, has continued his 

 work upon the American grasses and economic plants, visiting 

 the botanical gardens at Kew, Paris, Berlin and other places 

 in Europe for the purpose of making examinations of the col- 

 lections. During this work he has secured a large number 

 of specimens of living material for the conservatories. 



Mrs. E. G. Britton, voluntary assistant, has continued her 

 studies of the mosses of North America, and has also worked 

 over collections from the West Indies and South America, 

 brought in various expeditions. A critical examination has 

 been made of the genus Semato-phyllum, and five thousand 

 specimens properly named and labeled have been added to 

 the systematic collection of mosses. Mrs. Britton has also 

 arranged an exchange of about five thousand specimens. 



Mr. R. S. Williams, museum aid, who was detailed on 

 leave to accompany an exploring expedition to eastern Bolivia 

 in July, 1901, returned in November, 1902, bringing a large 

 collection of preserved and living plants from that region, 



