J. Tue CLIMATE AND PYSICAL ASPECTS OF THE EQUATORIAL Zuxe.

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

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

Intluence of the Heat of the Soil - Influence of the Aqueons Vapour of

the Atmosphere---Intluence of Winds on the Temperature of the Equator

--Ileat due to the Condensation of Atmosplieric Vapour---General

Features of the Equatorial Climate--L'niformity of the Equatorial Cli-

mate 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---('oncluding

Remarks.

pagos 1-26

II. EQUITORIAL VEOETITION.

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

torial Forests---Low-growth Forest-trees-Flowery Trunks and their

Probable Callse-l'ies of Equatorial Forest-trees --The Climbing Plants

of the Equatorial Forests ---Palms-l'ses of Palm-trees and their Pro.

ducts-Ferns-Ginger-worts and Wild Lanan:s-- Arumis--Screw-Pines-

Orchids--- Bamboos -l'ses of the Damboo- Mangroves-Sensitive-plants

--Comparative Scarcity of Flowers--Concluing Remarks on Tropical

Vegetation

parjes 27—68

III. ANTAL LIFE IS TE TROPICAL Forests.

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

Forests - Diurnal Lepidoptera or Lutterilies-Peculiar Habits of Tropical

Butterflies-- Ants, Wasps, and Bees--Ants-Special Relations between

Ants and Vegetation-Wasps and Dees-- Orthoptera and other Insects-

Beetles-Winless Insects-General Olo-crvations on Tropical Insects-

Birds--Parrots-Pigrons-Picerie --Cuckoos - Trogons, Burbets, Toucans

and Hornbills -- Passcres-- Reptiles and Amphibii- Lizards-- Snakes-

Frogs and Tous-Vammalia-Monkeys-Bits - Summary of the Aspects

of Animal Life in the Topics.

piges 09--123

IV. Hruuisg-BIRDS: As IllustrATING TIIS LUXURIANCE of

Tropical NATURE.

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

Habits of Humwing-Birus-Display of Ornaments by the Mule--Food

--Gevraphical Distribution and Variation-IIumming-Dirils of Juan

Fernandez as illustrating Variation and Natural Selection, The Relations

and Illinities of Ilumming - Lirils - How to Determine Doubtful Afinities
- Resemblances of Swists and Humming-Birds-Differences between
Sun-birds and IIumming-Lirds ..

pages 121-157

V. Tue COLOURS OF ASTMALS AND SEXCAL SELECTION.

General Phenomena of Colour-Theory of Ileat an:l Light as producing

Colour-Changes of Culour in Animals produced by Coloured Light-

Classitication of 01.zinic Colours--- Protective Colours --Wrning Colours

-Sexual Colours-Typical Colours - The Nature of Colour-How Inimal

Colours are Produced-('olour a Normal Provluct of Organization - Theory

of Protective Colours- Theory of Warning Colours - Imitative Warning

('olours, The Theory of Mimicry— Theory of Sexual Colours-Colour

as a means of Recognition-Colour proportionate to Interimentary

Development --Selection by Females not a Cause of Colour--- Probable Use

of the Horns of Bretles-Cause of the greater Drilliancy of some Female

Insect3---Origin of the Ornamental Plumage of Male Birds--- Theory of

the Dipl:ty of Ornaments by Vales - Vatural Selection as neutralizing

Sexual Selection-Greater Brilliancy of some Female Birds-Colour-

development as illustrated by IIumming-Birds-- Theory of Typical Colours

-Local Causes of Colour-levelopment-Summary on Colour-development

in Animals-Concluding Remarks on Causes of Bright Colour in the

Tropies.

Diges 153-220

VI. Tue COLOURS OF PLANTS AND THE ORIGIN OF THE COLOUR-SESSE.

Sonrce of Colouring-matter in Plants--Protective Coloration and Mimicry

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

Secils how Protected-Attractive Colours of flowers-Attractive Odours

in Flowers- Attractive Grouping in Flowers-Why Alpine Flowers are so

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

Absence of Colours in Winel-fertilized 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 the

Direct Action of Light on the Colours of Flowers and fruits—Concluding

Remarks on the Importance of Colour in the Organic World-Tue ORIGIN

OF THE C'OLOUP-LESSE.--Supposeel sucre.se of Colour-perception within

the Hi-turical Period - Concluding Piemir'is on the Colour-sense

PJ:8 221–219

VII. BY-PATHS IN THE DOMAIN OF BIOLOGY.

BEING AX ADDRESS DELIVERED TO THE BIOLOGICAL SECTION OF THE BRITISH

ASSOCIATION (GLASGOW, SEPTEMBER Ori, 1876) AS PRESIDENT OF THE SECTION,

Introductory Remarks-Ox SOME RELATIONS OF Livixo TuusGS TO THEIR

ExvIROSJEST.--The Intluence of Locality on Colour in Butterflies and Birds--Sense-perception influenced by Colour of the IntegumentsRelations of Insular Plants and Insects-RISE AND PROGRESS OF Moderx Views AS TO TIE ANTIQUITY AND Origin Of Max-Indications of Man's Extreme Antiquity-Antiquity of Intellectual ManSculptures on Easter-Islaud-North American Earthworks--The Great Pyramid-Conclusion

pages 219-303

VIII. Tue DISTRIBUTION OF ANIMALS AS INDICATING GeograPHICAL

CHANGES. Old Opinions on Continental Changes-Theory of Occanic Islands--- Present

and Past Distribution of Land and Sea-Zoological Regions—The Palaearctic Region- The Ethiopian Region - The Oriental Region-Past changes of the Great Eastern Continent-Regions of the New World--Past His. tory of the American Continents—The Australian Region-Summary and Conclusion

pages 301-317

TROPICAL NATURE,

AND OTHER ESSAYS.