CONTENTS xiii 



PAGE 



an illustration — ^Migration of a troupial — Fear in birds 

 and false associations — Direction of migration — Un- 

 rest — Flying north — Migration of rock-swallow — Pull 

 of the north — Perturbations in migration — Upland 

 plover ......... 183 



XIII 



No hard and fast line between migrants and non-migrants 

 — Swallows and partridges — Contrasted behaviour in 

 two mocking-birds — Spur-wing lapwing — An instinct in 

 a state of flux — Migration in other creatures — Fishes 

 and insects — Kirby and Spence speculate — Spiders — 

 Mammals — Migration a danger — Sand-grouse and 

 the "Tartar invasions of Europe" — A "sense of 

 polarity " the origin of migration — A trace of this 

 sense in man ....... 205 



XIV 



The pampas Indian's battle-cry — Terrifying effects of sound 

 generally — Other aspects of sound — Effect of a power- 

 ful sneeze — The human voice at its loudest — Account 

 of a man with a big voice — Sound in the ears of the 

 drowning — Sound of big bells heard in a belfry — A 

 great thunder-clap — The phenomenon and the dream 

 — The wilderness of the mind . . . .227 



XV 



The rhea's voice — Sounds that carry farthest — Man and 

 animals compared as to voice power — The swift's 

 flight — Melody — Music as art and instinctive — Mam- 

 malian music — Capybara — Quis — Tuco-tuco — Singing 

 mouse and small rodents — Monkeys — Braying of the 

 ass as music — A purge for the mind — The ass in fable 

 and folk-story ....... 239 



