CONTENTS XI 



The Lungs 364 



Changes in the Lungs at Birth . 367 



Anomalies 368 



References for Further Study 369 



CHAPTER XIV 



THE DEVELOPMENT OF THE CCELOM, THE PERICARDIUM, PLEUROPERITONEUM, 



DIAPHRAGM AND MESENTERIES 370 



The Pericardial Cavity, Pleural Cavities and Diaphragm 371 



The Pericardium and Pleura 378 



The Omentum and Mesentery 378 



The Greater Omentum and Omental Bursa 378 



The Lesser Omentum 379 



The Mesenteries 380 



The Peritoneum 382 



Anomalies 382 



References for Further Study 383 



CHAPTER XV 



THE DEVELOPMENT OF THE UROGENITAL SYSTEM 384 



The Pronephros 384 



The Mesonephros 386 



The Kidney (Metanephros) 391 



The Ureter, Renal Pelvis, and Straight Renal Tubules 391 



The Convoluted Renal Tubules and Glomeruli 393 



The Renal Pyramids and Renal Columns 397 



Changes in the Position of the Kidneys 399 



The Urinary Bladder, Urethra, and Urogenital Sinus 400 



The Genital Glands 403 



The Germinal Epithelium and Genital Ridge 403 



Differentiation of the Genital Glands 405 



The Ovary 406 



The Testicle 411 



Determination of Sex 412 



The Ducts of the Genital Glands and the Atrophy of the Meso- 



nephroi 413 



In the Female 413 



Oviduct 414 



Uterus and Vagina 415 



In the Male 416 



Changes hi the Positions of the Genital Glands and the Development 



of their Ligaments 417 



Descent of the Testicles 419 



Descent of the Ovaries 422 



