CONTENTS 
Changes in Movements—New Ways of Look- 
ing after the Young—New Kinds of Protec- 
tion—Betwixt-and-Between Animals—Haunts 
within Haunts—Beneath the Ground—Cave 
Animals—Arboreal Life 
CHAPTER VI 
THE MASTERY OF THE AIR 
What Getting into the Air meant—The Flight of 
Insects—Why are there so many Insects ?— 
The Flying Dragons—The Flight of Birds— 
Different Kinds of Flying in Birds—Migration 
the Climax—The Fourth Solution of Flight— 
Fitnesses of Birds and Bats—Attempts at 
Flight—Gossamer Spiders 
Index . 
xi 
PAGE 
185 
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270 
