ogy, laws of, explained by variations not
supervening at an early age, and being inherited at a corresponding
age--Rudimentary Organs; their origin explained--Summary.

CHAPTER XV.

RECAPITULATION AND CONCLUSION.

Recapitulation of the objections to the theory of Natural
Selection--Recapitulation of the general and special circumstances
in its favour--Causes of the general belief in the immutability
of species--How far the theory of Natural Selection may be
extended--Effects of its adoption on the study of Natural
history--Concluding remarks.

GLOSSARY OF SCIENTIFIC TERMS.

INDEX.

ORIGIN OF SPECIES.

INTRODUCTION.

When on board H.M.S. Beagle, as naturalist, I was much struck with
certain facts in the distribution of the organic beings inhabiting South
America, and in the geological relations of the present to the past
inhabitants of that continent. These facts, as will be seen in the
latter chapters of this volume, seemed to throw some light on the origin
of species--that mystery of mysteries, as it has been called by one
of our greatest philosophers. On my return home, it occurred to me,
in 1837, that something might perhaps be made out on this question by
patiently accumulating and reflecting on all sorts of facts which could
possibly have any bearing on it. After five years' work I allowed myself
to speculate on the subject, and drew up some short notes; these I
enlarged in 1844 into a sketch of the conclusions, which then seemed to
me probable: from that period to the present day I have steadily pursued
the same object. I hope that I may be excused for entering on these
personal details, as I give them to show that I have not been hasty in
coming to a decision.

My work is now (1859) nearly finished; but as it will take me many more
years to complete it, and as my health is far from strong, I have been
urged to publish this abstract. I have more especially been induced to
do this, as Mr. Wallace, who is now studying the natural history of
the Malay Archipelago, has arrived at almost exactly the same general
conclusions that I have on the origin of species. In 1858 he sent me a
memoir on this subject, with a request that I would forward it to Sir
Charles Lyell, who sent it to the Linnean Society, and it is published
in the third volume of the Journal of that Society. Sir C. Lyell and Dr.
Hooker, who both knew of my work--the latter having read my sketch
of 1844