THE FOUNDATIONS OF THE
ORIGIN OF SPECIES

CAMBRIDGE UNIVERSITY PRESS
London: FETTER LANE, E.C.
C. F. CLAY, Manager

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ALSO
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From a photograph by Maull & Fox in 1854

THE FOUNDATIONS OF THE
ORIGIN OF SPECIES
TWO ESSAYS
WRITTEN IN 1842 AND 1844
by
CHARLES DARWIN

Edited by his son
FRANCIS DARWIN
Honorary Fellow of Christ's College

Cambridge:
at the University Press
1909

Astronomers might formerly have said that God ordered each planet to move in its particular destiny. In same manner God orders each animal created with certain form in certain country. But how much more simple and sublime power,—let attraction act according to certain law, such are inevitable consequences,—let animal«s» be created, then by the fixed laws of generation, such will be their successors.

From Darwin’s Note Book, 1837, p. 101.

TO THE MASTER AND FELLOWS
OF CHRIST’S COLLEGE, THIS
BOOK IS DEDICATED BY THE
EDITOR IN TOKEN OF RESPECT
AND GRATITUDE

CONTENTS

ESSAY OF 1842

• PAGES
  
• Introduction xi

PART I

• § i. On variation under domestication, and on the principles of selection 1
• § ii. On variation in a state of nature and on the natural means of selection 4
• § iii. On variation in instincts and other mental attributes 17

PART II

• §§ iv. and v. On the evidence from Geology. (The reasons for combining the two sections are given in the Introduction) 22
• § vi. Geographical distribution 29
• § vii. Affinities and classification 35
• § viii. Unity of type in the great classes 38
• § ix. Abortive organs 45
• § x. Recapitulation and conclusion 48

ESSAY OF 1844

PART I

CHAPTER I
ON THE VARIATION OF ORGANIC BEINGS UNDER DOMESTICATION; AND ON THE PRINCIPLES OF SELECTION.

• Variation
• On the hereditary tendency
• Causes of Variation
• On Selection
• Crossing Breeds
• Whether our domestic races have descended from one or more wild stocks
• Limits to Variation in degree and kind
• In what consists Domestication
• Summary 57-80

CHAPTER II
ON THE VARIATION OF ORGANIC BEINGS IN A WILD STATE; ON THE NATURAL MEANS OF SELECTION; AND ON THE COMPARISON OF DOMESTIC RACES AND TRUE SPECIES.

• Variation
• Natural means of Selection
• Differences between “Races” and “Species”:—first, in their trueness or variability
• Difference between “Races” and “Species” in fertility when crossed
• Causes of Sterility in Hybrids
• Infertility from causes distinct from hybridisation
• Points of Resemblance between “Races” and “Species”
• External characters of Hybrids and Mongrels
• Summary
• Limits of Variation 81-111

CHAPTER III
ON THE VARIATION OF INSTINCTS AND OTHER MENTAL ATTRIBUTES UNDER DOMESTICATION AND IN A STATE OF NATURE; ON THE DIFFICULTIES IN THIS SUBJECT; AND ON ANALOGOUS DIFFICULTIES WITH RESPECT TO CORPOREAL STRUCTURES.

• Variation of mental attributes under domestication
• Hereditary habits compared with instincts
• Variation in the mental attributes of wild animals
• Principles of Selection applicable to instincts
• Difficulties