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Memorrs of the Garden, which was issued under date of 
January 20, 1903. 
The duties of the Director-in-Chief were discharged dur- 
ing the absences of Dr. N. L. Britton in March and Decem- 
ber. Editorial work in connection with the Torrey Botanical 
Club has been performed, and the duties of Secretary of the 
Botanical Society of America have been discharged during 
the year. 
Photographic equipment has been provided for the several 
expeditions sent by the Garden to various parts of the world. 
Selections are made from the negatives secured by such 
means, which are registered and placed in the permanent col- 
lection, which now includes about 400. Lantern slides are 
made from the reserved negatives and from others as well, 
which are used in illustrating the lectures of the spring and 
autumn courses. These slides are also used by members 
of the staff in lectures given in other institutions. The most 
valuable addition to this collection consists of a series, 340 in 
number, donated by Mr. C, F. Cox, of the Board of Mana- 
gers. This series.;was made by Mr. T. F. Smith, of London, 
and illustrates the theory of structure of diatoms as described 
by him inthe Journal of the New York Microscopical Society 
for April, 1891. The collection of slides now amounts to 
about I,200. 
The experimental greenhouse and the adjacent ground in 
the nursery are proving of very great service in investigations 
in physiology, morphology and mycology. Since May, 1902, 
have been codperating with Professor Hugo de Vries, 
Director of the Botanical Garden at Amsterdam, Holland, in 
testing certain features of the mutation theory of the origin of 
species recently proposed by him. One series of cultures of 
the parent species of the evening primrose, and mutant forms 
derived from it, has been finished, and the results published 
in the American Naturalist for November, 1903, and re- 
printed as CONTRIBUTION 48 in the Garden publications. A 
second series has been begun. This work is of unusual in- 
terest, since it Is concerned with the only known instances 
