366808

N 111

ON

THE ORIGIN OF SPECIES

BY

MEANS OF NATURAL SELECTION,

OR THE

PRESERVATION OF FAVORED RACES IN THE STRUGGLE
FOR LIFE.

AUTHOR OF

BY

CHARLES DARWIN, M. A., F.R.S.,

66 JOURNAL OF RESEARCHES DURING H. M. S. BEAGLE'S VOYAGE ROUND
THE WORLD," ETC., ETC.

GELOSCHT

OFFENTL BUCHERHALLE

FIFTH EDITION, WITH ADDITIONS AND CORRECTIONS.

HAMBURG

NEWS

YORK:

D. APPLETON AND COMPANY,

549 & 551 BROADWAY.

1872.

OFFENTLICHE BUCHER

1901 $457.

HISTORICAL SKETCH

INTRODUCTION

CONTENTS

PAGE 9

17

CHAPTER I.

VARIATION UNDER DOMESTICATION.

Causes of Variability-Effects of Habit-Correlated Variation-Inheritance-Char-

acter 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 favorable to Man's Power of Selection 22

CHAPTER II.

VARIATION UNDER NATURE,

Variability-Individual Differences-Doubtful Species-Wide-ranging, much dif

fused, 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

52

CHAPTER III.

STRUGGLE FOR EXISTENCE.

ats bearing on Natural Selection-The Term used in a wide Sense-Geometrical Ratio

of Increase-Rapid Increase of Naturalized 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 through