PREFACE
LIST OF MAPS
CHAPTER I
MIGRATION OF BIRDS
CHAPTER II
CAUSE AND ORIGIN OF MIGRATION
CHAPTER III
ROUTES
CHAPTER IV
THE HEIGHT AND SPEED OF MIGRATION FLIGHT
CHAPTER V
ORIENTATION AND ROUTE FINDING
CHAPTER VI
THE DISTANCES TRAVELLED BY BIRDS
CHAPTER VII
MIGRATION AND WEATHER
CHAPTER VIII
THE PERILS OF MIGRATION
CHAPTER IX
EARLY IDEAS OF MIGRATION
CHAPTER X
SUGGESTIONS AND GUESSES
CHAPTER XI
SUMMARY
BIBLIOGRAPHY
INDEX
