plained by Natural Selection-Adaptation brought about by General

Laws-Beauty in Nature-How New Forms are produced by Varia-

tion and Selection-The Objection that there are Limits to Variation

-Objection to the Argument from Classification-The Times on

Natural Selection-Intermediate or generalised Forms of Extinct

Animals an indication of Transmutation or Development-Conclu-

sion-A Demonstration of the Origin of Species by Natural Selection

Pages 141-166

VIII. THE DEVELOPMENT OF HUMAN RACES Under the Law

OF NATURAL SELECTION

Wide differences of Opinion as to Man's Origin-Outline of the Theory

of Natural Selection-Different Effects of Natural Selection on

Animals and on Man-Influence of External Nature in the develop-

ment of the Human Mind-Extinction of Lower Races-The Origin

of the Races of Man-The Bearing of these Views on the Antiquity

of Man-Their Bearing on the Dignity and Supremacy of Man-

Their Bearing on the future Development of Man-Summary-Con-

clusion

167-185

IX. THE LIMITS OF NATURAL SELECTION AS APPLIED TO MAN

What Natural Selection can Not do-The Brain of the Savage shown

to be Larger than he Needs it to be-Size of Brain an important

Element of Mental Power-Comparison of the Brains of Man and of

Anthropoid Apes-Range of Intellectual Power in Man-Intellect of

Savages and of Animals compared-The use of the Hairy Covering

of Mammalia-The Constant Absence of Hair from certain parts of

Man's body a remarkable Phenomenon-Savage Man feels the want

of this Hairy Covering-Man's Naked Skin could not have been pro-

duced by Natural Selection-Feet and Hands of Man considered as

Difficulties on the Theory of Natural Selection-The Voice of Man-

-The Origin of some of Man's Mental Faculties, by the preservation

of Useful Variations, not possible-Difficulty as to the Origin of the

Moral Sense-Summary of the Argument as to the Insufficiency of

Natural Selection to account for the Development of Man-The

Origin of Consciousness-The Nature of Matter-Matter is Force

-All Force is probably Will-force-Conclusion
186-214

TROPICAL NATURE AND OTHER ESSAYS

I. THE CLIMATE AND PHYSICAL ASPECTS OF THE EQUATORIAL

ZONE

The three Climatal Zones of the Earth-Temperature of the Equatorial

Zone-Causes of the Uniform High Temperature near the Equator—

Influence of the Heat of the Soil-Influence of the Aqueous Vapour

of the Atmosphere-Influence of Winds on the Temperature of the

Equator Heat due to the Condensation of Atmospheric Vapour—

General Features of the Equatorial Climate-Uniformity of the

Equatorial Climate in all Parts of the Globe-Effects of Vegetation

on Climate Short Twilight of the Equatorial Zone-The Aspect of

the Equatorial Heavens-Intensity of Meteorological Phenomena at

the Equator-Concluding Remarks

Pages 217-237

II. EQUATORIAL VEGETATION

The Equatorial Forest-belt and its Causes-General Features of the Equa-

torial Forests-Characteristics of the Larger Forest-Trees-Flowering

Trunks and their Probable Cause-Uses of Equatorial Forest-trees-

The Climbing Plants of the Equatorial Forests-Palms-Uses of Palm-

trees and their Products-Ferns-Ginger-worts and Wild Bananas-

Arums-Screw-pines-Orchids-Bamboos-Uses of the Bamboo-Man-

groves-Sensitive Plants-Comparative Scarcity of Flowers-Con-

cluding Remarks on Tropical Vegetation

238-269

III. ANIMAL LIFE IN THE TROPICAL FORESTS

Difficulties of the Subject-General Aspect of the Animal Life of Equa-

torial Forests-Diurnal Lepidoptera or Butterflies-Peculiar Habits of

Tropical Butterflies-Ants, Wasps, and Bees-Ants-Special Rela-

tions between Ants and Vegetation-Wasps and Bees-Orthoptera

and other Insects-Beetles-Wingless Insects-General Observations

on Tropical Insects-Birds-Parrots-Pigeons-Picaria-Cuckoos—

Trogons, Barbets, Toucans, and Hornbills-Passeres-Reptiles and

Amphibia Lizards-Snakes-Frogs and Toads-Mammalia: Mon-

keys Bats-Summary of the Aspects of Animal Life in the Tropics

270-311

IV. HUMMING-BIRDS: AS ILLUSTRATING THE LUXURIANCE OF

TROPICAL NATURE

Structure-Colours and Ornaments-Descriptive Names-The Motions and

Habits of Humming-birds-Display of Ornaments by the Male-Food

-Nests-Geographical Distribution and Variation-Humming-birds

of Juan Fernandez as illustrating Variation and Natural Selection-

The Relations and Affinities of Humming-birds-How to Determine

Doubtful Affinities-Resemblances of Swifts and Humming-birds-

Differences between Sun-birds and Humming-birds-Conclusion

Pages 312-337

V. THE COLOURS OF ANIMALS AND SEXUAL SELECTION

General Phenomena of Colour in the Organic World-Theory of Heat and

Light as producing Colour-Changes of Colour in Animals produced

by Coloured Light-Classification of Organic Colours-Protective

Colours-Warning Colours-Sexual Colours-Normal Colours-The

Nature of Colour-How Animal Colours are produced-Colour a

Normal Product of Organisation-Theory of Protective Colours-

Theory of Warning Colours-Imitative Warning Colours-The Theory

of Mimicry-Theory of Sexual Colours-Colour as a means of

Recognition-Colour proportionate to Integumentary Development-

Selection by Females not a cause of Colour-Probable use of the

Horns of Beetles-Cause of the greater Brilliancy of some Female

Insects-Origin of the Ornamental Plumage of Male Birds —

Theory of the Display of Ornaments by Males-Natural Selection

as neutralising Sexual Selection-Greater Brilliancy of some Female

Birds - Colour - development as illustrated by Humming - birds -

-Theory of Normal Colours-Local causes of Colour-development-

The influence of Locality on Colour in Butterflies and birds-Sense-

perception influenced by Colour of the Integuments-Summary on

Colour-development in Animals
338-394

VI. THE COLOURS OF PLANTS AND THE ORIGIN OF THE

COLOUR-SENSE

Source of Colouring Matter in Plants-Protective Coloration and Mimicry

in Plants-Attractive Colours of Fruits-Protective Colours of Fruits

-Attractive Colours of Flowers-Attractive Odours in Flowers-

Attractive Grouping of Flowers-Why Alpine Flowers are so Beauti-

ful-Why Allied Species of Flowers differ in Size and Beauty-

Absence of Colour in Wind-fertilised Flowers-The same Theory of

Colour applicable to Animals and Plants-Relation of the Colours

of Flowers and their Geographical Distribution - Recent Views as

to Direct Action of Light on the Colours of Flowers and Fruits-

Concluding Remarks on the Importance of Colour in the Organic

World-On the Origin of the Colour-sense: Supposed Increase of

Colour-perception within the Historical Period—Concluding Remarks

on the Colour-sense.
Pages 395-415

VII. THE ANTIQUITY AND ORIGIN OF MAN

Indications of Man's extreme Antiquity-Antiquity of Intellectual Man

-Sculptures on Easter Island-North American Earthworks-The

Great Pyramid-Conclusion

416-432

VIII. THE ANTIQUITY OF MAN IN NORTH AMERICA

Ancient Shell Mounds-Man Coeval with Extinct Mammalia-Man in

the Glacial Period-Palæolithic Implements in North America-The

Auriferous Gravels of California-Fossil Remains under the Ancient

Lava Beds Works of Art in the Auriferous Gravels-Human

Remains in the Auriferous Gravels-Concluding Remarks on the

Antiquity of Man

433-449

IX. THE DEBT OF SCIENCE TO DARWIN

The Century before Darwin-The Voyage of the Beagle-The Journal

of Researches Studies of Domestic Animals-Studies of Cultivated

and Wild Plants-Researches on the Cowslip, Primrose, and Loose-

strife-The Struggle for Existence-Geographical Distribution and

Dispersal of Organisms-The Descent of Man and later Works-

Estimate of Darwin's Life-Work

450-475

INDEX

476

ESSAYS ON NATURAL SELECTION

B