preparation of the volume. Mrs J.A. Thomson kindly undertook the
translation of the essays by Prof. Weismann and Prof. Schwalbe; Mrs James
Ward was good enough to assist me by translating Prof. Bougle's article on
Sociology, and to Mr McCabe I am indebted for the translation of the essay
by Prof. Haeckel. For the translation of the botanical articles by Prof.
Goebel, Prof. Klebs and Prof. Strasburger, I am responsible; in the
revision of the translation of Prof. Strasburger's essay Madame Errera of
Brussels rendered valuable help. Mr Wright, the Secretary of the Press
Syndicate, and Mr Waller, the Assistant Secretary, have cordially
cooperated with me in my editorial work; nor can I omit to thank the
readers of the University Press for keeping watchful eyes on my
shortcomings in the correction of proofs.

The two portraits of Darwin are reproduced by permission of Messrs Maull
and Fox and Messrs Elliott and Fry. The photogravure of the study at Down
is reproduced from an etching by Mr Axel Haig, lent by Mr Francis Darwin;
the coloured plate illustrating Prof. Weismann's essay was originally
published by him in his "Vortrage uber Descendenztheorie" which afterwards
appeared (1904) in English under the title "The Evolution Theory". Copies
of this plate were supplied by Messrs Fischer of Jena.

The Syndics of the University Press have agreed, in the event of this
volume being a financial success, to hand over the profits to a University
fund for the endowment of biological research.

It is clearly impossible to express adequately in a single volume of Essays
the influence of Darwin's contributions to knowledge on the subsequent
progress of scientific inquiry. As Huxley said in 1885: "Whatever be the
ultimate verdict of posterity upon this or that opinion which Mr Darwin has
propounded; whatever adumbrations or anticipations of his doctrines may be