2 Introductory Letter 
Darwin and to be his companion during many of his working hours 
in Study, Laboratory, and Garden. I was the recipient of letters 
from him, relating mainly to the progress of his researches, the copies 
of which (the originals are now in the possession of his family) cover 
upwards of a thousand pages of foolscap, each page containing, on an 
average, three hundred words. 
That the editorship of these Essays has been entrusted to a 
Cambridge Professor of Botany must be gratifying to all concerned in 
their production and in their perusal, recalling as it does the fact 
that Charles Darwin’s instructor in scientific methods was his lifelong 
friend the late Rev. J. S. Henslow at that time Professor of Botany in 
the University. It was owing to his recommendation that his pupil 
was appointed Naturalist to H.M.S. Beagle, a service which Darwin 
himself regarded as marking the dawn of his scientific career. 
Very sincerely yours, 
J. D. HOOKER. 
