XVI PHYSIOLOGY AND MORPHOLOGY OF ANIMALS. 



SECTION III. 

 Blood Circulation — Vertebrates. 



Circulation in man, 375. General course of, 376. Diagrams illus- 

 trating, 377, 378. Structure of the heart : valves, 380. Blood vessels : 

 (1) Arteries, (2) veins, 382 ; (3) capillaries, 383. 



Comparative Morphology of Blood System in Vertebrates. — Mam- 

 mals, birds, reptiles and amphibians, 385. Diagram of the course, 386. 

 Fishes, diagram of, 388. 



Bearing of these Fads on Evolution.— (1) Heart structure, (2) aor- 

 tic arches and their relation to gill arches, 390. Diagram of origin of 

 aortic arches in birds, 394. In mammals, 395. Illustration of a funda- 

 mental law of evolution, 396. 



SECTION IV. 

 Morphology of Respiratory and Circulatory System in Invertebrates. 



Introductory, 397. Crustacea, respiratory organs of, mode of breath- 

 ing, 399. Circulation, diagram illustrating, 400. Mollusca : Acephala, 

 respiration, 401 ; circulation, 402 ; gastropods, 403 ; cephalopoda, 404. 

 Echinoderms, 404. Coslenterata, protozoa, 406. Insects, why passed 

 over, 407. Blood system, 408. Respiratory system, 409. Air tubes, 

 410. Breathing, 411. 



SECTION V. 



Lymphatic or Absorbent System. 



General description, distribution, 411. Structure, function, lym- 

 phatic glands, 413. Function, comparative morphology of lymphatic 

 system, 414. 



CHAPTER IV. 



KATABOLISM. 

 SECTION I. 

 Introductory, 415. Secretion vs. excretion, 416. 



SECTION II. 



Function of Respiration. 



(1) Chemistry of respiration. 418. (2) Purpose of combustion, (3) 

 the fuels, 419. (4) How is force created? 420. Illustrative diagram, 

 422. Place of the combustion, 423. Relation of plants to animals in 

 the creation of animal force, 424. 



