CONTENTS. 



PAGE 



Introduction, ........... 5 



The Function of Birds in Nature, . 7 



Utility of Insect-eating Birds, . . . . . 14 



Quantity of Insects eaten by Young Birds, . . .... . . 18 



Quantity of Insect Food required by Adult Birds, .... 19 



Crops and Trees saved from Destruction by Birds, .... 20 



Decrease of Birds followed by Increase of Destructive Insects, . . 37 



Increase of Birds followed by Decrease of Destructive Insects, . . 42 



Birds as Weed Destroyers, ......... 45 



Birds as Distributors and Planters of Seeds, . . . * . . .46 

 Birds as Scavengers, . . . . . . . . .47 



Utility of Birds of Prey, 47 



Services rendered by Shore Birds, Marsh Birds, Waterfowl and Sea Birds, . 53 



Cash Value of Birds' Services 60 



Utility of Birds in War 63 



Commercial Value of Birds, ......... 64 



Early Abundance of Game Birds, . . . . . . .65 



Game Birds as Food, ......... 65 



Eggs of Sea Birds as Food 69 



Feathers of Sea Birds and Wild-fowl for Bedding 70 



Feathers for Ornament 72 



Shooting Birds for Sport, ......... 75 



Value of Birds in Domestication, 76 



Fertility from the Sea Immense Value of Guano Deposits, . . 77 



Esthetic, Sentimental and Educational Value of Birds, 80 



484681 



