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NEW EDITION, FROM THE SIXTH ENGLISH EDITION, WITH ADDITIONS
AND CORRECTIONS.

NEW YORK:
D. APPLETON AND COMPANY,

1, 3, And 5 BOND STREET,

1888.

46 But with regard to the material world, we can at least go w for Uj 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."

Wuewell: Brhljcicatcr 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"

Botlek: Analogy of Revealed lleli'jCoti.

"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 at God's works; divinity or philosophy; but rather let men endeavour ata endless progress or proficience in both."

Bacon: Advancement of Learning.

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CONTENTS.

Additions And Corrections, To The Sixth Edition .. Pageir-m

Historical Sketch ziii-xxt

Introduction 1-1

CHAPTER I.

Variation Under Domestication.

Causes of Variability — Effects of Habit and the use or disuse of Parts —

Correlated Variation — 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 fol-

lowed, their Effects — Methodical and Unconscious Selection — Un-

known Origin of our Domestic Productions — Circumstances favour-

able to Man's power of Selection 5-H2

CHAPTER II.

Variation Under Nature.

Variability — Individual differences — Doubtful species — Wide raaging,

much diffused, and common species, vary most — Species of the larger

genera in each country vary more frequently 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 , 33-47

CHAPTER III.

Struggle For Existence.

Its bearing on natural selection — The term used in a wide sense—Geome-

trical ratio of increase—Rapid increase of naturalised animals and

plants—Nature of the checks to increase — Competition universal—

Effects of climate — Protection from the number of individuals —

Complex relations of all animals and plants throughout nature —

Struggle for life most severe between individuals and varieties of th<

same species: often severe between species of the same genus—Tht

relation of organism to organism the most important of all rela-

tions -. 4&-61

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