RESPIRATORY APPARATUS 193 Nostrils and Nasal Chambers 193 Pharynx and Superior Larynx 193 Trachea 194 Inferior Larynx 194 Bronchi and the Lungs 195 Air-sacs 199 ANGIOLOGY CIRCULATORY APPARATUS 206 Heart 206 Structure of the Heart 207 Blood-vessels 209 Structure of the Capillaries and Arteries 209 Structure of the Veins 211 Arterial Trunks 211 Branches of: Arteria Brachiocephalica 213 Arteria Carotis Cerebralis Interna 214 Arteria Carotis Externa 214 Arteria Carotis Facialis 214 Aorta Posterior 224 Venous Trunks 233 Branches of: Venæ Cavæ Anteriores 234 Vena Jugularis 237 Vena Occipitalis Externa 239 Venous Sinuses of the Head 239 Veins of the Brain Cavity 241 Veins of the Neck 242 Branches of the Vena Subclavia 243 Veins of the Dorsal Region 243 Veins of the Thorax 244 Veins of the Fore Limb 245 Branches of the Iliaca 246 Branches of the Vena Iliaca Interna 247 Posterior Vena Cava 247 Veins of the Posterior Extremity 248 Branches of the Vena Cava Posterior 248 Veins of the Caudal Region and Pelvic Cavity 250 Veins of the Truncus Vena Iliaca Communis 252 Visceral Veins of the Posterior Vena Cava 252 Lymphatic System 254 BLOOD AND ITS FUNCTIONS 257 FATE OF THE ERYTHROCYTE 261