VI 



CONTENTS. 



Page. 



Mastication, - 101 



Teeth of Man, - - - 111 



Teeth of the Tiger, - - 112 



Teeth of the Antelope, - 113 



Teeth of the Rat, - - 114 

 Masticating organs of Man 



and the Mammalia, - 114 



Organs of Digestion, - - 116 

 Human Stomach, - - 116 

 Gastric juice, - - - 117 

 Chemical effects of the Gas- 

 tric juice, - - - 118 



Comparative Digestion, - 119 



Stomach of the Sheep, - - 119 



Rumination, - 121 

 Relation of the horns and 



stomach, - 121 

 Water cells in Camels' stom- 

 ach, .... 121 

 Water cells in Elephants' 



stomach, - - - . 122 



Food of Man and other Ani- 

 mals, - - - - 123 

 Elements of Nutrition, - - 123 

 Food nutritive and digestible, 123 

 Man requires a variety of food, 124 

 Dr. Starks' Experiments, - 125 

 Dr. Magendie's Experiments, 126 

 Dr. Cooper's Experiments, - 126 

 . Beaumont's Ex 



Dr 



xperiments, 127 



PART IV. 



CIRCULATION OP THE BLOOD, 131 



Circulation in Insects, - - 132 



Circulation in the Frog, - 133 



Circulation in Fishes, - - 134 

 Circulation in warm blooded 



Animals, - - - 135 



Two hearts separated, - - 136 



Two hearts united, - - 136 



The two hearts act together, 138 

 Number of pulsations of the 



heart, - 138 

 Effects of Alcohol on the cir- 

 culation, - - - 139 

 Alcohol not the product of dis- 

 tillation, - 140 

 Muscular force of the heart, 142 



Respiration, .. - - 143 



Respiration, in the Oyster, - 144 



Respiration in Fishes, - - 145 



Respiration in the Lamprey, 146 



Page. 



Atmospheric Respiration, - 146 



Respiration in Insects, - - 147 



Respiration in Reptiles, - 148 



Respiration in the Frog, - 149 



Respiration in Birds, - - 150 



Lungs of the Ostrich, - - 151 



Respiration in the Mammalia, 153 

 Respiration in Man, - - 153 

 Trunk of the Human Skeleton, 154 

 Situation of the diaphragm, 155 

 Human lungs and heart, - 156 

 Chemical effects of Respira- 

 tion, - 157 

 Animal heat, - 159 



PART V. 



SENSORIAL FUNCTIONS, - - 160 



Brain and Nerves, - - 160 



Nervous Ganglions, - - 162 



Vision, - - - - 163 



Structure of the Human Eye, 163 



Structure of the Iris, - 165 



Physiology of Vision, - - 166 



Cause of the inverted image. 169 



Motions of the Eye, - - 173 

 Magnitudes and distances, 174 

 Insensibility to certain col- 

 ors, .... 177 

 Comparative Physiology of 



Vision, - - - 178 



Eyes of Insects, - - - 179 



Eyes of Fishes, - - - 182 



Eyes of Birds, - - - 183 



Audition, or Hearing, 185 



Auditory organs in Man, - 187 



Bones of the Ear, - - 190 



Physiology of hearing, - 192 

 Comparative Physiology of 



hearing, - - - 193 



Hearing in the Lobster, - 194 



Hearing in the Frog, - - 194 



Hearing in Birds, - - 196 



Musical Ear, - - - 197 

 Musical Ear situated in the 



Brain, - - - - 199 



Organs of Smell, - - 200 

 Olfactory nerves in the Duck, 201 

 Audubonon the smell of Vul- 

 tures, - - - - 202 



