CONTENTS. 
xv 
CHAPTER XXIII. 
ON THE ARCTIC ELEMENT IN SOUTH TEMPERATE FLORAS. 
European species and genera of plants in the Southern Hemisphere — Aggressive power 
of the Scandinavian flora — Means by which plants have migrated from north to 
south — Newly moved soil as affording temporary stations to migrating plants — 
Elevation and depression of the snow-line as aiding the migration of plants — 
Changes of climate favourable to migration — The migration from north to south 
has been long going on — Geological changes as aiding migration — Proofs of mi- 
gration by way of the Andes — Proofs of migration by way of the Himalayas and 
Southern Asia — Proofs of migration by way of the African highlands — Supposed 
connection of South Africa and Australia — The endemic genera of plants in New 
Zealand — The absence of Southern types from the Northern Hemisphere — 
Concluding remarks on the New Zealand and South Temperate floras 
Pages 477 — 498 
CHAPTER XXIY. 
SUMMARY AND CONCLUSION. 
The present volume is the development and application of a theory — Statement of 
the Biological and Physical causes of dispersal — Investigation of the facts of dis- 
persal — of the means of dispersal — of geographical changes affecting dispersal — 
of climatal changes affecting dispersal — The Glacial Epoch and its causes — Alleged 
ancient glacial epochs — "Warm polar climates and their causes — Conclusions as to 
geological climates — How far different from those of Mr. Croll — Supposed limita- 
tions of geological time— Time amply sufficient both for geological and biological 
development — Insular faunas and floras— The North Atlantic Islands — The Gala- 
pagos — St. Helena and the Sandwich Islands— Great Britain as a recent Conti- 
nental Island — Borneo and Java — Japan and Formosa — Madagascar as an ancient 
Continental Island — Celebes and New Zealand as anomalous Islands — The Flora 
of New Zealand and its origin— The European element in the South Temperate 
Floras— Concluding Remarks Pages 499 — 512 
