CONTENTS xi 



PAGE 



ments New Ways of Looking after the Young New 

 Kinds of Protection Betwixt-and-Between Animals 

 Haunts within Haunts Beneath the Ground Cave 

 Animals Arboreal Life . . . .185 



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 . .231 



Index . . . , . . 270 



