Chapter II: Preface: Pages

vii—x

LIST OF SOME OF THE PRINCIPAL AUTHORITIES QUOTED, _Pages_
WITH AN ENUMERATION OF THE AUTHOR’S BOTANICAL xiii—xv
PAPERS

LIST OF ILLUSTRATIONS _Page_
xxvii

ADDITIONS AND CORRECTIONS _Page_
xxviii

CHAPTER I

INTRODUCTION

The study of insular floras.—Their investigation in this work from the
standpoint of dispersal.—The significance of plant-distribution in the
Pacific.—The problems connected with the mountain-flora of Hawaii.—The
persistence of dispersing agencies at the coast, their partial
suspension on the mountain-top, their more or less complete suspension
in the forest, and the effect on the endemic character of plants.—The
connection between the endemism of birds and plants.—The relative
antiquity of plants of the coast, forest, and mountain-top.—The
genetic relation between coast and inland species of the same
genus.—The ethics of plant-dispersal.—Evolution takes no heed of modes
of dispersal.—The seed-stage is the price of Adaptation.

_Pages_ 1-11

CHAPTER II

THE FLORAS OF THE PACIFIC ISLANDS FROM THE STANDPOINT OF DISPERSAL
BY CURRENTS

The initial experiment.—The proportion of littoral plants.—The two great
principles of buoyancy.—The investigations of Professor Schimper.—The
investigations of the author.—The great sorting process of the
ages.—Preliminary results of the inquiry into the buoyancy of seeds
and fruits.

_Pages_ 12-22

CHAPTER III

THE LESSON OF THE BRITISH FLORA

Results of observations on the buoyancy of over 300 British plants.—The
small proportion of plants with buoyant seeds or seedvessels.—Their
station by the water-side.—The great sifting experiment of the
ages.—Summary.

_Pages_ 23-30

CHAPTER IV

THE LESSON OF THE BRITISH FLORA (_continued_)

The choice of station of the water-side plant possessing buoyant seeds
or seedvessels.—Determined by its fitness or unfitness for living in
physiologically dry stations.—In the internal organisation of a plant
lies the first determining influence of station.—The grouping of the
British strand-plants.—Whilst the Xerophyte with buoyant seed or fruit
finds its station at the coast, the Hygrophyte similarly endowed makes
its home at the river or pond side.—The grouping of the plants of the
river and the pond.—Summary.

_Pages_ 31-39

CHAPTER V

THE FIJIAN STRAND-FLORA

The inland extension of the beach-plants.—The grouping of the
coast-plants.—Their modes of dispersal.—The zone of change.—Summary.

_Pages_ 40-46

CHAPTER VI

THE TAHITIAN STRAND-FLORA

(_From materials supplied mainly by the work of Drake del Castillo_)

Lacks the mangroves and their associated plants.—Possesses mainly the
plants of the coral beach.—Predominant agency of the currents.—Inland
extension of shore-plants.—Summary

_Pages_ 47-50

CHAPTER VII

THE HAWAIIAN STRAND-FLORA

Its poverty.—Its negative features.—Their explanation.—The subordinate
part taken by the currents.—The Oregon drift.—The inland extension of
the beach-plants.—Summary

_Pages_ 51-60

CHAPTER VIII

THE LITTORAL PLANTS AND THE CURRENTS OF THE PACIFIC

The working value of the currents as plant-dispersers.—The relation
between the currents and the distribution of shore-plants.—The clue
afforded by the American plants.—Two regions of tropical shore-plants,
the American and the Asiatic.—America, the home of the cosmopolitan
tropical shore-plants that are dispersed by the currents.—Hawaii and
the currents.—Summary

_Pages_ 61-75

CHAPTER IX

THE GERMINATION OF FLOATING SEEDS

Germination in the floating seed-drift of tropical estuaries.—A strain
of vivipary.—Abortive germination of seeds in warm seas.—A barrier to
plant dispersal.—The borderland of vivipary.—Summary

_Pages_ 76-87

CHAPTER X

THE RELATION OF THE BUOYANCY OF SEEDS AND SEEDVESSELS TO THE DENSITY
OF SEA-WATER

The general principles concerned.—The subject assumes a statistical
character.—Seeds and seedvessels are as a rule either much heavier
than sea-water or much lighter than fresh water.—The present littoral
plants with buoyant seeds or seedvessels could be equally well
dispersed by currents in oceans of fresh water.—Seed-buoyancy has no
relation either in the present or in the past to the density of the
sea.—Though an accidental attribute, the specific weight of seeds has
had a profound influence on plant-distribution.—Summary

_Pages_ 88-98

CHAPTER XI

ADAPTATION AND MEANS OF DISPERSAL

Nature has never concerned herself directly with providing means of
dispersal.—Fleshy fruits not made to be eaten.—Nor “sticky” seeds to
adhere to plumage.—Nor prickly fruits to entangle themselves in fur
and feathers.—The dispersal of seeds a blind result of the struggle
between the intruding Evolutionary power and the controlling influence
of Adaptation.

_Pages_ 99-103

CHAPTER XII

THE CAUSES OF THE BUOYANCY OF SEEDS AND FRUITS OF LITTORAL PLANTS,
WITH ESPECIAL REFERENCE TO THOSE OF THE PACIFIC ISLANDS

The classification of buoyant seeds and fruits.—The first group, where
the cavity of the seed or seedvessel is incompletely filled.—The
second group, where the kernel is buoyant.—The third group, where
there is air-bearing tissue in the seed-tests or fruit-coats.—The
buoyant seeds and seedvessels of the littoral plants of the British
flora.—Summary

_Pages_ 104-118

CHAPTER XIII

ADAPTATION AND SEED-BUOYANCY

The question of the operation of Natural Selection.—Are there two
principles at work?—The presence of buoyant tissue in the seed-tests
and fruit-coats of inland plants, both wild and cultivated.—Useless
buoyancy.—The buoyancy of seeds and fruits is not concerned with
Adaptation.—Summary.

_Pages_ 119-129

CHAPTER XIV

THE RELATION BETWEEN LITTORAL AND INLAND PLANTS

Professor Schimper’s views.—Great antiquity of the
mangrove-formation.—Problem mainly concerned with the
derivation of inland from littoral plants.—Grouping of
the genera possessing both coast and inland
species.—Scævola.—Morinda.—Calophyllum.—Colubrina.—Tacca.—Vigna.—Premna

_Pages_ 130-139

CHAPTER XV

THE RELATION BETWEEN LITTORAL AND INLAND PLANTS (_continued_)

Inland species of a genus developed from littoral species originally
brought by the currents but no longer existing in the
group.—Illustrated by the Leguminous genera Erythrina, Canavalia,
Mezoneuron, and Sophora, and by the Apocynaceous genus Ochrosia.—The
Hawaiian difficulty.

_Pages_ 140-154

CHAPTER XVI

THE RELATION BETWEEN LITTORAL AND INLAND PLANTS (_continued_)

The Fijian difficulty.—Inland species of a genus possessing
fruits not known to have any means of dispersal through
agencies now at work in the Pacific.—Pandanus.—Its remarkable
distribution in oceanic groups.—To be attributed perhaps
to extinct Columbæ or extinct Struthious
birds.—Barringtonia.—Guettarda.—Eugenia.—Drymispermum.—Acacia
laurifolia.—Conclusions to be drawn from the discussion.—Summary of
Chapters XIV., XV., XVI.

_Pages_ 155-169

CHAPTER XVII

THE STORIES OF AFZELIA BIJUGA, ENTADA SCANDENS, AND CÆSALPINIA
BONDUCELLA

Afzelia bijuga.—The African home of the genus.—The double station of
Afzelia bijuga, inland and at the coast.—The nature of the buoyancy
of its seeds.—Summary relating to Afzelia bijuga.—Entada
scandens.—Its station and distribution.—Darwin’s opinion of the
plant.—The dispersal of its seeds by the currents.—Summary relating
to the plant.—Cæsalpinia bonducella and C. bonduc.—Their station and
distribution.—Their characters in various Pacific groups.—The
parents of inland species.—Their dispersal by the currents.—The
germination of their seeds.—A dream of vivipary.—The causes of the
seed-buoyancy.—Summary of results

_Pages_ 170-197

CHAPTER XVIII

THE ENIGMAS OF THE LEGUMINOSÆ OF THE PACIFIC ISLANDS

Leguminosæ predominate in tropical littoral floras.—The anomalies of
their distribution in the Pacific islands.—They conform to no one rule
of dispersal or of distribution.—Strangers to their stations.—The
American home of most of the Leguminous littoral plants.—Summary

_Pages_ 198-203

CHAPTER XIX

THE INLAND PLANTS OF THE PACIFIC ISLANDS

PRELIMINARY COMPARISON OF THE PHYSICAL CONDITIONS OF HAWAII,
FIJI, AND TAHITI

Introductory remarks.—The tranquil working of the winds and currents
contrasted with the revolutionary influence of the bird.—The Hawaiian,
Fijian, and Tahitian groups.—Their surface-areas and elevations.—Their
climates.—The mountain climate of Hawaii.—The rainfall of the three
groups.—Summary

_Pages_ 204-219

CHAPTER XX

THE ERAS IN THE FLORAL HISTORY OF THE PACIFIC ISLANDS

THE AGE OF FERNS

The eras in the plant-stocking.—The age of ferns and lycopods.—The
relative proportion of vascular cryptogams in Hawaii, Fiji, and
Tahiti.—The large number of peculiar species in Hawaii.—The mountain
ferns of Hawaii.—The origin of peculiar species.—Dr. Hillebrand’s
views.—Their origin connected not with greater variety of climate in
Hawaii, but with isolation.—Summary

_Pages_ 220-230

CHAPTER XXI

THE ERAS OF THE FLOWERING PLANTS

THE ERA OF THE ENDEMIC GENERA

THE AGE OF COMPOSITÆ

The islands of the tropical Pacific as the homes of new genera and new
species.—The significance of a large endemic element.—Synopsis of the
eras.—The era of endemic genera.—The endemic genera of
Compositæ.—Their affinities and mode of dispersal.—The mystery of the
suspension of the dispersing agencies.—Mr. Bentham’s views.—The
remnant of an ancient Composite flora in the tropical Pacific.—The
dispersion of the Compositæ antedates the emergence of the
island-groups of the Fijian region at the close of the Tertiary
period.—Summary

_Pages_ 231-249

CHAPTER XXII

THE ERA OF THE ENDEMIC GENERA (_continued_)

THE AGE OF THE TREE-LOBELIAS

The distribution of the arborescent Lobeliaceæ.—On the upper flanks of
Ruwenzori.—The Lobeliaceæ of the Hawaiian Islands.—The Lobeliaceæ of
the Tahitian or East Polynesian region.—The capacities for
dispersal.—The explanation of the absence of the early Lobeliaceæ from
West Polynesia.—The other Hawaiian endemic genera.—The Fijian endemic
genera.—Summary

_Pages_ 250-267

CHAPTER XXIII

THE ERA OF THE NON-ENDEMIC GENERA OF FLOWERING PLANTS

THE MOUNTAIN FLORAS OF THE PACIFIC ISLANDS AS ILLUSTRATED BY
THE NON-ENDEMIC GENERA

The mountain-flora of Hawaii.—A third of it derived from high southern
latitudes.—An American element.—Compared with Tahiti and
Fiji.—Capacities for dispersal of the genera possessing only endemic
species.—Acæna, Lagenophora, Plantago, Artemisia, Silene, Vaccinium,
&c.—Capacities for dispersal of the genera possessing non-endemic
species.—Cyathodes, Santalum, Carex, Rhynchospora.—Fragaria chilensis,
Drosera longifolia, Nertera depressa, Luzula campestris.—Summary.

_Pages_ 268-288

CHAPTER XXIV

THE ERA OF THE NON-ENDEMIC GENERA OF FLOWERING PLANTS (_continued_)

THE MOUNTAIN-FLORAS OF THE TAHITIAN AND FIJIAN REGIONS

The mountain-flora of the Tahitian region, as illustrated by the
non-endemic genera.—Derived chiefly from high southern
latitudes.—Weinmannia, Coprosma, Vaccinium, Astelia, Coriaria,
Cyathodes, Nertera depressa, Luzula campestris.—The mountain flora of
Rarotonga.—The mountain-flora of the Fijian region, as illustrated by
the non-endemic genera.—Weinmannia, Lagenophora, Coprosma, Astelia,
Vaccinium, Nertera depressa.—The Fijian Coniferæ.—Dammara, Podocarpus,
Dacrydium.—Not belonging to the present era of dispersal.—The age of
dispersal of the Coniferæ in the Pacific.—Earlier than the age of
Compositæ and Lobeliaceæ.—The first in the Mesozoic period.—The last
in the Tertiary period.—Summary

_Pages_ 289-306

CHAPTER XXV

THE ERA OF THE NON-ENDEMIC GENERA OF FLOWERING PLANTS (_continued_)

THE AGE OF THE MALAYAN PLANTS AS REPRESENTED IN THE LOW-LEVEL FLORA OF
HAWAII AND IN THE BULK OF THE FLORAS OF THE FIJIAN AND TAHITIAN
REGIONS

THE AGE OF WIDE DISPERSAL OVER THE TROPICAL PACIFIC

The widely dispersed genera which possess only peculiar species in
Hawaii.—Pittosporum.—Reynoldsia.—Gardenia.—Psychotria.—Cyrtandra.—Freycinetia.—Sapindus.—Phyllanthus.—Pritchardia.—Summary.

_Pages_ 307-332

CHAPTER XXVI

THE ERA OF THE NON-ENDEMIC GENERA OF FLOWERING PLANTS (_continued_)

THE AGE OF MALAYAN PLANTS (_continued_)

THE AGE OF WIDE DISPERSAL OVER THE TROPICAL PACIFIC (_continued_)

The widely dispersed genera that are as a rule not entirely
represented by endemic species in any
archipelago.—Elæocarpus.—Dodonæa.—Metrosideros.—Alyxia.—Alphitonia.—Pisonia.—Wikstrœmia.—Peperomia.—Eugenia.—Gossypium.—The
last stage in the general dispersal of plants of the Malayan
era as illustrated by the widely-dispersed genera having
as a rule no peculiar
species.—Rhus.—Osteomeles.—Plectronia.—Boerhaavia.—Polygonum.—Pipturus.—Dianella.—Summary.

_Pages_ 333-358

CHAPTER XXVII

THE ERA OF THE NON-ENDEMIC GENERA OF FLOWERING PLANTS (_continued_)

THE AGE OF MALAYAN PLANTS (_continued_)

THE AGE OF LOCAL DISPERSAL

Synopsis of the Chapter given on page 359

_Pages_ 359-410

CHAPTER XXVIII

THE POLYNESIAN AND HIS PLANTS

Identity of the problems presented by the indigenous plants and the
peoples of the Pacific islands.—The food-plants of the Polynesians and
the pre-Polynesians.—Their weeds.—The aboriginal weeds.—The white
man’s weeds.—Weeds follow the cultivator but are distributed by
birds.—The general dispersion of weeds antedates the appearance of the
Polynesian in the Pacific.—Weeds of little value to the
ethnologist.—Aleurites moluccana.—Inocarpus edulis, Gyrocarpus
Jacquini, Serianthes myriadenia, Leucæna Forsteri, Mussænda frondosa,
Luffa insularum.—Summary

_Pages_ 411-428

CHAPTER XXIX

BEACH AND RIVER DRIFT

In the south of England.—On the coast of Scandinavia.—In the
Mediterranean.—Southern Chile.—Very little effective dispersal by
currents in temperate latitudes.—Cakile maritima.—In tropical
regions.—River drift.—River and beach drift of Fiji.—Musa Ensete.—The
coco-nut.—River and beach drift of Hawaii.—Comparison of the beach
drift of the Old and New Worlds.—Summary

_Pages_ 429-439

CHAPTER XXX

THE VIVIPAROUS MANGROVES OF FIJI

RHIZOPHORA AND BRUGUIERA

_Rhizophora._—Represented by Rhizophora mucronata, Rhizophora
mangle, and the Selala, a seedless intermediate form.—Their
mode of association and characters.—The relation of the
Selala.—Polyembryony.—The history of the plant between the
fertilisation of the ovule and the detachment of the seedling.—Absence
of a rest period.—Mode of detachment of the seedling.—Capacity
for dispersal by the currents.—_Bruguiera._—The mode of
dispersal.—Peculiar method of fertilisation.—Length of period between
fertilisation and the detachment of the seedling.—Mode of detachment
of the seedling.—Summary

_Pages_ 440-467

CHAPTER XXXI

A CHAPTER ON VIVIPARY

The significance of vivipary.—The scale of germinative capacity.—A lost
habit with many inland plants.—The views of Goebel.–-The shrinking in
the course of ages of tropical swamp areas.—The variation in the
structures concerned with vivipary.—Abnormal vivipary.—Summary.

_Pages_ 468-473

CHAPTER XXXII

THE WEST COAST OF SOUTH AMERICA

The littoral floras of the West Coast of South America.—The Convolvulus
soldanella zone of Southern Chile.—The plantless or desert zone of
Northern Chile.—The Sesuvium zone of Peru.—The Mangrove zone of
Ecuador and Colombia.—The two varieties of Rhizophora mangle, the
“mangle chico” and the “mangle grande.”—The floating vegetable drift
of the Guayaquil River.—The Humboldt current and the climate of the
West Coast of South America.—The advance northward of the arid
climatic conditions of the Peruvian sea-border.—The retreat of the
mangroves.—Evidence of ancient coral reefs on the coast of Peru.—The
shore plants and stranded seed-drift of the Panama Isthmus.—Summary.

_Pages_ 474-501

CHAPTER XXXIII

SEED-DISPERSAL AND GEOLOGICAL TIME

The shifting of the source of Polynesian plants from the New to the Old
World.—The floral history of Polynesia stated in terms of geological
time.—The suspension of the agencies of dispersal in later
periods.—Parallel differentiation in the course of ages of climate,
bird, and plant.—New Zealand.—Insects and bats as agents in
plant-dispersal.—The effective agency of sea-birds in other
regions.—The observations of Ekstam.—The Spitzbergen controversy.—The
efficacy of ducks as distributors of aquatic plants.—Summary

_Pages_ 502-514

CHAPTER XXXIV

GENERAL ARGUMENT AND CONCLUSION _Pages_ 515-523