THE RESPIRATORY SYSTEM RESPIRATORY SYSTEM OF THE HORSE 436 The Nasal Cavity 436 The Larynx 440 The Trachea 448 The Bronchi 450 The Thoracic Cavity 450 The Pleuræ 451 The Lungs 453 THE THYROID GLAND OF THE HORSE 457 THE THYMUS OF THE HORSE 458 RESPIRATORY SYSTEM OF THE OX 458 RESPIRATORY SYSTEM OF THE PIG 464 RESPIRATORY SYSTEM OF THE DOG 466 THE UROGENITAL SYSTEM URINARY ORGANS OF THE HORSE 469 The Kidneys 469 The Ureters 475 The Urinary Bladder 475 THE ADRENAL BODIES 477 URINARY ORGANS OF THE OX 478 URINARY ORGANS OF THE PIG 481 URINARY ORGANS OF THE DOG 483 THE MALE GENITAL ORGANS MALE GENITAL ORGANS OF THE HORSE 485 The Testicles 485 The Scrotum 487 The Vas Deferens 488 The Spermatic Cord 489 The Tunica Vaginalis 489 Descent of the Testicles 490 The Vesiculæ Seminales 491 The Prostate 493 The Uterus Masculinus 493 The Bulbo-urethral Glands 493 The Penis 494 The Prepuce 496 MALE GENITAL ORGANS OF THE OX 500 MALE GENITAL ORGANS OF THE PIG 504 MALE GENITAL ORGANS OF THE DOG 506