CONTENTS. 



Ingenuity of Insects, 70 



Caddis worm, 72 



PART II. 



VETEBRATED ANIMALS, 75 



Animals resist heat and cold, 76 



Structure of the bones, 80 



Formation and growth of bone, 83 



Spine of the vertebrata, - 84 



Form of the vertebra, 85 

 Skeleton of the human trunk 



and arms, 86 



Unity manifested in the spines, 88 

 Mechanical elements of the 



vertebra, 89 



Vertebra of Fish, - - 90 



Locomotion of Fishes, - 91 



Spines of Birds and Fishes, - 95 



Skeleton of the Swan, - - 95 

 Comparison of the bones of 



Men and Birds, - - 96 . 



PART III. 



97 

 98 

 98 

 98 



ANIMAL FUNCTIONS, 



Sources of Nutrition, - 

 Vegetable food, - - Vrrivv 

 Animal food, - 

 Relation between animals and 



their food, - 100 



Man omnivorous, - - 100 



Animal Nutrition, - - 101 

 Complexity of Stomach in the 



high orders, - 102 



Man eats every thing, - - 102 



Grinding of Food, - - 103 

 Grinding in the Lobster, - 104 

 Gizzards of Birds, - - 104 



Organs of nutrition and vi- 

 tality in the Mammalia, 106 



Plan of the most important 



Viscera, - - 107 



Circulation of the blood, - 109 



