ON THE

ORIGIN OF SPECIES.

"But with regard to the material world, we can at least go so far as this-we can perceive that events are brought about not by insulated interpositions of Divine power, exerted in each particular case, but by the establishment of general laws."

WHEWELL: Bridgewater Treatise.

"The only distinct meaning of the word 'natural' is stated, fixed, or settled; since what is natural as much requires and presupposes an intelligent agent to render it so, i. e. to effect it continually or at stated times, as what is supernatural or miraculous does to effect it for once."

BUTLER: Analogy of Revealed Religion.

"To conclude, therefore, let no man out of a weak conceit of sobriety, or an ill-applied moderation, think or maintain, that a man can search too far or be too well studied in the book of God's word, or in the book of God's works; divinity or philosophy; but rather let men endeavour an endless progress or proficience in both."

BACON: Advancement of Learning.

Down, Bromley, Kent,

November 24th, 1859. (1st Edition.)

Fourth Edition, June, 1866.

ON

THE ORIGIN OF SPECIES

BY MEANS OF NATURAL SELECTION,

OR THE

PRESERVATION OF FAVOURED RACES IN THE STRUGGLE
FOR LIFE.

BY CHARLES DARWIN, M.A., F.R.S., &c.

FOURTH EDITION, WITH ADDITIONS AND CORRECTIONS.

(EIGHTH THOUSAND.)

LONDON:

JOHN MURRAY, ALBEMARLE STREET.

1866.

The right of Translation is reserved.

189. f. 17

BY THE SAME AUTHOR.

A NATURALIST'S VOYAGE ROUND THE WORLD; or, A

JOURNAL OF RESEARCHES into the NATURAL HISTORY and GEOLOGY of the
COUNTRIES Visited during the Voyage of H. M. S. Beagle, under the Command of
Capt. Frrz-Rox, R. N. Post 8vo. 98.

MURRAY.

With numerous

RAY SOCIETY. HARDWICKE.

A MONOGRAPH OF THE CIRRIPEDIA.
Illustrations. 2 vols. 8vo.

ON THE VARIOUS CONTRIVANCES BY WHICH BRITISH AND FOREIGN ORCHIDS ARE FERTILISED BY INSECTS; and on the GOOD EFFECTS of CROSSING. With Woodcuts. Post 8vo. 98. MURRAY.

ON THE MOVEMENTS and HABITS of CLIMBING PLANTS.
With Woodcuts.
WILLIAMS & NORGATE.

Preparing for Publication.

DOMESTIC ANIMALS AND CULTIVATED PLANTS; or, The PRINCIPLES of VARIATION, INHERITANCE, REVERSION, CROSSING, INTERBREEDING, and SELECTION, UNDER DOMESTICATION.

LONDON: PRINTED BY W. CLOWES AND SONS, STAMFORD STREET,
AND CHARING CROSS.

Causes of Variability-Effects of Habit-Correlation of Growth-
Inheritance-Character of Domestic Varieties-Difficulty of
distinguishing between Varieties and Species-Origin of Domestic
Varieties from one or more Species-Domestic Pigeons, their
Differences and Origin-Principles of Selection anciently followed,
their Effects-Methodical and Unconscious Selection-Unknown
Origin of our Domestic Productions-Circumstances favourable
to Man's power of Selection

7-45

CHAPTER II.

VARIATION UNDER NATURE.

-

Wide-

Variability Individual differences Doubtful species
ranging, much-diffused, and common species vary most-Spe-
cies of the larger genera in each country vary more than the species
of the smaller genera-Many of the species of the larger genera
resemble varieties in being very closely, but unequally, related
to each other, and in having restricted ranges

46-69