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Dr. Francis W. Pennell was appointed Associate Curator 
in September. He has been occupied in general herbarium 
work, and has continued investigations on certain groups of 
the figwort family, in addition to working on the bibliog- 
raphy of the whole family preliminary to a monograph of 
it for North American Flora. Dr. Pennell also incidentally 
studied portions of the collections of flowering plants from 
the southern states which were made on several exploring 
expeditions through that region. 
Miss Margaret Slosson, Assistant Curator, devoted her 
time to the care and development of the collection of ferns 
and fern allies. She added valuable specimens to the 
herbarium by means of exchanges in this country and 
abroad, and presented her own fern herbarium to the 
Garden, selecting many of the rarer kinds from it for perma- 
nent incorporation in the Garden herbarium, and using the 
remainder as duplicates for exchanging. Miss Slosson 
published two papers on American ferns, and made progress 
on some monographic work for North American Flora. 
Dr. H. H. Rusby, Honorary Curator of the Economic 
Collections, continued to develop the collections of the 
Economic Museum. For details, see his report. 
Mrs. E. G. Britton, Honorary Curator of Mosses, con- 
tinued to care for and develop the collection of mosses, with 
the assistance of Mr. R. S. Williams. Her report appears 
elsewhere in this publication. 
Dr. Arthur Hollick, Honorary Curator of Fossil Plants, 
continued, with the assistance of Mr. Edwin W. Hum- 
phreys, the work he initiated in former years. For par- 
ticulars, see report of the Honorary Curator of the Collec- 
tion of Fossil Plants. 
Early in the year, I pursued supplementary studies on 
the families Monotropaceae and Ericaceae at the National 
Museum and at the herbarium of Harvard University. 
The monographs of these families were published about the 
middle of the year. Preliminary work on other families 
for North American Flora was initiated. Considerable 
