Vlll CONTENTS. 



PAGE 



Brain I4 o 



Brain of cyclostomes 152 



Brain of elasmobranchs 153 



Brain of teleostomes 153 



Brain of dipnoi 155 



Brain of amphibia 155 



Brain of reptiles 157 



Brain of birds 158 



Brain of mammals 158 



Peripheral nervous system 161 



Spinal nerves 161 



Sympathetic system 163 



Cranial nerves 165 



Sensory organs 177 



Nerve-end apparatus 178 



Lateral line organs ' . 179 



Auditory organs 182 



Organs of taste. 189 



Olfactory organs 189 



Eyes 198 



Digestive organs 205 



Oral cavity 208 



Teeth 208 



Tongue 217 



Oral glands 220 



Pharynx 222 



(Esophagus 222 



Stomach 223 



Intestine 227 



Liver 231 



Pancreas 234 



Respiratory organs 235 



Gills (branchiae) 236 



Pharyngeal derivatives 245 



Swim bladder 247 



Lungs and air ducts 250 



Air ducts 251 



Lungs . . 255 



Accessory respiratory structures 263 



Organs of circulation 264 



Blood and lymph ' 265 



Blood-vascular system 266 



Embryonic circulation . . . . ' 268 



Heart 269 



Arteries 273 



Veins 276 



